C4 corvette high idle problems. around 1500 and after a minute or two it raises up to 1800.

C4 corvette high idle problems Or if you - Chevrolet 1989 Corvette question Search Fixya Oct 29, 2023 · C4 Tech/Performance - Idle too high! - Hello, I own a 1984 c4 corvette. Aug 6, 2007 · C4 Tech/Performance - High Idle Problem - Hello everyone, After installing a set of the new Accel 24lb fuel injectors in my ’90 coupe, I have been having a problem w/ high idle (about 1100 rpm). The idle oscillates between 600 and 700 RPM on occasion, but at least the engine no longer dies at a stop sign. When driving it, it is low on power and you feel it missing. It?s got a high idle which usually sits at about 1600 rpm, sometimes at 2000 though. Jun 24, 2009 · This tech paper will discuss the procedure for correct adjustment of the Minimum Idle Speed and for adjustment of the Throttle Position Switch (TPS) on the early C4 Corvette TPI systems. When the car is first started it idles smoothly. The digital and analog temp guage reads about the same when running down the road. luper007 Jan 3, 2023 · Metal oxidizes. Usually it idles right at 800, 850 with the air on, just like we set it with LS1 Edit, 4 years ago. thanks mike Feb 5, 2015 · C3 General - Rochester Carb High Idle problem - On cold start it high idles at around 1200 rpms fine and kicks down when warm to 750 rpms which is great but after driving it the idle wont go down to 750 rpms when you stop and clutch is in. Dec 2, 2012 · C4 Tech/Performance - 1993 high idle - I just got done doing opti and waterpump after bleeding the cooling system I fired up the car. any ideas of what to look at. Apr 2, 2007 · It sounds like you need to replace your PCV valve and fuel filter. Today I put the scan tool on it. I'm new here and you all seem to have some amazing knowlege between you and I thought I'd pick your brains since the shop can't figure anything out. My thoughts would be that the timing might be out, or the idle air control motor might be messed up, or you need to adjust your idle. Oct 30, 2024 · The engine idle was still oscillating badly while driving it home from the shop. It's an intermittant problem. and found this info: NOTE: If you do manage to use a 1984 computer module from a manual transmission Corvette in a 1982 Corvette without reprogramming the EPROM Chip, you will get a problem with a very high idle RPM. Jump to Latest "Desiree" - 1977 - Wife's car, with an attitude problem. I put the old TPS back in and the idle decreased to about 1000 rpm. When I first start the car it runs rough and idles poor after about ten minutes its ok to drive. When you first start it, it idles fine for about 20 seconds then starts running really rough (definite miss) and trips a P300 (Random Misfire Code). :lookinup: Save Share Mar 14, 2013 · C4 Tech/Performance - High idle, 90 L98, let's talk IAC - I bought this car last month in NC and drove it home 6hrs. AND, it had the idle May 17, 2002 · Engine Mods - High idle problem with a new Holley Street Avenger - HELP! - I have a new Holley Street Avenger on a new small block in my '75 that I just got from the shop yesterday. I have read and have been told at least ten different ways of adjusting the base idle. I finally pulled it a couple weeks ago. Oct 23, 2020 · C4 Tech/Performance - High Idle at start up - Brand new to this forum. Oct 4, 2008 · C4 Corvette Forums. Cold start= everything totally normal. The motor not stock it a mild build it has a chip for the mods. When I first start it the idle is allways about 1200 rpm for awhile then the idle drops to about 900 rpm. Apr 30, 2005 · C4 Tech/Performance - 88 Crazy High Idle Problem! PLEASE Help! - New iac;new egr valve;vacuum looks good, no visual leaks; removed 52mm throttle body and cleaned, opens/closes OK; correct TPS sensor reading; throttle cables look good, -no binding. I have a High Idle problem that I have been trying to resolve, I have did a Tune up of the usual parts, rebuilt the Throttle body with new gaskets, New IAC Valve. Since I've had it, the engine has bogged down a bit when first put into gear (somewhat intermittent, may be tied to engine temp). I put new gaskets and a new TPS Jan 25, 2011 · C4 Corvette Forums. when it's cold it runs very rough but when it reaches operating Mar 31, 2020 · C4 Corvette General Discussion 1988 idle problems. Fluctuations of 3 to 4 inches Hg, indicate sticking valves. Thanks Jun 20, 2007 · C4 Tech/Performance - high idle - Everytime now that I come to a stop my car is idling at around 1300 - 1500 RPM. Mine starts up at 800 rpm cold and when Apr 3, 2016 · C4 Tech/Performance - Another LT1 High Idle issue - Hello all, I have a 92 LT1. I tried loosening the idle screw in the picture and lubricating the whole throttle Jul 12, 2008 · Idle problems I have a 1986 4+3 that I just brought 2 months ago and have been having the same problem. Jump to Latest 7. Vacuum readings at idle much lower than normal indicate leakage through intake manifold gaskets, manifold-to-carburetor gaskets, vacuum brakes or the vacuum modulator. It has new plugs and wires and the cap and rotor look fine. This i gonna be long but bare with me. Two days later I went to crank it and I noticed it was idling really high, around 4300 rpm!!!! I noticed the upper intake manifold gasket had folded Dec 5, 2011 · C4 Tech/Performance - Bad Idle--1986 - Hello. When I shift into drive, the car does a heavy jerk forward and I usually have my foot on the brakes because when i shift into Dec 11, 2006 · C4 Tech/Performance - Intermittent high idle problem. Uh oh. Mechanical Issues. I May 29, 2014 · C4 Tech/Performance - 88 high idle with misfire problem - I have an 88, automatic with 42K miles, all stock. Feb 16, 2023 · C4 Tech/Performance - C4 high and surging idle - I?ve got a 1990. From what I have seen regarding the 82 Crossfire is that they should be around Aug 8, 2021 · While the intent of this page is to identify the common issues pertaining to the 1995 Corvette, it is not an all-inclusive list and should be used for reference only. C4 Corvette 1990 C4 idle surging in gear. I'm thinking the fast idle may be because Aug 2, 2011 · C4 Tech/Performance - Extremely high Idle RPM - A couple weeks ago I had trouble cranking my vette, 1990. thanks Mar 10, 2011 · I dont have any vacume leaks the base Idle is set at 450 RPM's the Normal timiming set a 6 advance. I dont remember the motor doing this before the rebuild from stock motor. No engine light, no codes. Replaced Apr 12, 2014 · C4 Tech/Performance - High idle problem - Okay first off I'm new to the forum I've got a 1985 coupe completely stock except for the basic open air box, & 160 thermo. 53, IAC 20, MAF 12-17. May 22, 2017 · I pulled in to my drive and the popped the hood. How long has it had this problem? Give me a little more info on the problems your having with the miles on the motor, Should be an easy fix. The time and mileage intervals for each of the maintenance items included on this page were established by General Motors with the introduction of the 1996 Chevy Corvette. My main problem is the car has an extremely high idle. After going through everything that Sep 25, 2009 · C4 Tech/Performance - 84 Crossfire idle too high ! - Hi guys ! what can be causing my friend's 84 idle to high ? Tomorrow he is coming to visit me and i will ride a 84 for the first time thanks. Nov 15, 2024 · C3 Tech/Performance - 82 Crossfire high idle - vacuum leak? - I'm working on tracking down a high idle as it currently is, it idles around 1000 RPMS at warm and in park. Since then my car has acted strangely (forgive me but I do not know all the technical jargon so bear with me): When I accelerate slowly Oct 14, 2008 · If there is lots of miles on the cars the shaft thru the throttle body can wear to a point it will bind as you slowly back off the gas pedal and make it idle high, Fuel injector's starting to go bad and dripping gas at an idle instead of a fine mist can cause this problem, Low fuel pressure or stopped up fuel filter. It has 76,000 miles on it. also it seems slow to drop in rpm when you rev it slightly. I have a 1984 Corvette with Crossfire, about 75k miles on it. C4 Tech/Performance L98 Corvette and LT1 Corvette problem was the same May 19, 2013 · C4 General Discussion - High idle problem solved - Since buying my 1991 in September it has idled high. In drive it idles around 550. I'm hoping someone else has had this problem and knows the fix. The Opti-Spark Ignition System has been known to fail on late model C4 Corvettes (those equipped with PFI V8 engines). Thank you all for tuning in to another video!SIGN THE RPM ACT TO HELP SAVE OUR RACECARS!!-- https://www. - I just bought this 99 convertible and it idles at close to 2k rpm. A couple weeks ago I performed a complete tune up (new plugs&wires, air filter, oil&filter change) I cleaned all Jan 22, 2003 · C4 ZR-1 Discussion - High Idle Problem - Bottom is background: I've been waiting to pull my plenum to re-route the vacuum canister line to the correct place and check/tighten the vacuum system. I have a 87 auto that I drive on the weekends. C4 Corvette 1986 Idle. I'm having trouble with the cross fire injection. I start the car with no problems, it goes to high idle and as it warms, the idle starts May 25, 2017 · C4 Tech/Performance - 84 Crossfire Idle/IAC help - Hoping you guys can help me out. When you turn the key on, the tach needle moves to about 900 rpms, then when you start the engine the tach goes up to full peg then down to May 27, 2011 · C3 Tech/Performance - idle problems - I have a 1982 corvette which I just got for a birthday present from my wife and I'm having an isssue with it running really rich like it's flooding. The throttle bodies are known for causing "wandering" idle problems because of excessive housing wear where the throttle shaft goes in them. Jun 29, 2020 · C4 Tech/Performance - Idle problems - So thank you all for your contribution with respect to my timing problem. Also as far as a stuck egr, it depends how far open the egr is stuck,if its stuck wide open the car will surge and stall,if its stuck slightly open it will idle ruff and likely surge at steady cruise speed, if its stuck closed you will have higher Jun 5, 2009 · 1989 Corvette starting and idle problems My 60K mile Corvette has begun to start only when it is cold. Someone has tried to do alot of work to this car but it is definitely a restoration project and I don't know if it's just something loose or Oct 29, 2009 · C4 Tech/Performance - 85 High Idle Problem - I've been trying to get to the bottom of a problem with idling too high. 84 Crossfire Idle Problems. I was able to drop the idle to around 1,000 by adjusting the idle screw, but that's C4 Tech/Performance - Help me with my LT1 high idle, out of ideas - Back story: I bought a 92 in July and have been slowly bringing it back to working order. Idles at around 800 to 900. Last Summer I Changed The Intake Manifold Gaskets, While Doing That I Did A Major Tune-up Plugs,wires,cap,rotor,pcv C4 Tech/Performance - L98 High idle issue - hello i have an 87 L98, the idling is everywhere, it goes really high to high haha, ranges from 1800-1500RPM. This is a well known problem with C4 cooling issues. So I backed it off, next day it was way to Sep 8, 2015 · C4 Corvette Forums. Jan 14, 2008 · I have a problem of High Idle on my 88' TPI C4. Goes from 800 rpm's up to 1500, 1600 to 1700 rpm's at times. It never increased or decreased. Today I was driving and wanted to give it Jun 19, 2011 · C4 Corvette General Discussion. chip (aftermarket prom) 4. If I shut the car Dec 31, 2020 · Was researching the C3/C4 ECM change. throttle screw 2. I believe the problem may be the radiator but I might be wrong. He tried over and over with Mar 11, 2010 · C4 Tech/Performance - 1994 Running hot/ surging idle issue - My 94 Coupe runs fine when started and runs nice and cool going down the road. Save Jan 9, 2019 · C3 Tech/Performance - High-idle - Hi everyone, I've got my first vette and only waited 38 years to get it! :) Now the problems start - she idles high. 1993 was the worst year for Corvette for wire and this car is what inspired GM to create GMLAN and network ECU's together so as to save on wiring redundancies. I am still trying to figure out the exact problem. 8K The idle is high (about 1200-1400) But if I blip the throttle it comes down to May 19, 2014 · C4 Tech/Performance - High IDLE cause? - OK, I have checked all!! I checked the timing and it is set to 6*, I spent almost 1 hour looking for vac leak and got nothing, adjusted TPS to . It smokes like crazy and wants to stall. It is throwing the following three codes: DTC P0133 HO2S Slow Response Bank 1 Sensor 1 DTC P1134 HO2S Transition Time Ratio Bank 1 Sensor 1 DTC Sep 29, 2023 · C4 Tech/Performance - 1986 C4 Corvette Oscillating Idle Problem: - I have a 1986 C4 Corvette that I've had for about 9 months that's developed an idling problem. The idle speed of the car was always around 1000/1100 rpm, I thought the Idle Valve Control was malfunctioning, so I replaced it. I finally fixed the The initial idle is way too high. The System has been completely flushed more than 3 times and it overheats at idle and up to speed. Anyhow, I've read many different forums of what could cause a high idle, but let me explain my problem first (before I try anything else). I have a 96 LT1 that has been sitting for about 5 years and had a BBK throttle body and performance MAF May 24, 2005 · C5 Tech - Rough Idle! - Problem Solved And I Want To Share - Well, I am sure that a few of you guys have been following my aggraviation and know that I have been living with a rough idle and back firing and sluggish take-offs and well, I finally got this fixed! I did the following to the car to get the hassel: Added Aug 10, 2005 · C4 ZR-1 Discussion - High Idle problem on start up - Car will idle between 1500 - 2000 rpm on start up in the morning and stay there until it warms up, then it will drop to about normal. The idle goes up and down as it pleases. Starts and idles OK at 800 rpm, but once I depress the gas all hell May 24, 2006 · C4 General Discussion - 1987 Corvette troubles: high idle - A buddy of mine asked me to help him out with his 1987 Corvette. Hopefully that's it, and it's a pretty cheap fix! 1990 Midnight Blue Pearl Corvette, Z-51, 6 Speed, Ansa Performance Mufflers, Walker rear Y, ZR-1 Wheels, K&N + open lid, chip, GS Flares. if i step on the gas it comes back to idle at almost 2000rpm. not sticking throttle either - My idle hangs at 1100-1300rpm on occasion, and bumping the throttle brings it down. it runs perfect first time after Jul 19, 2021 · C4 Tech/Performance - 1986 Base Idle Adjustment - I know this has been explained many times but. Apr 14, 2006 · C4 Tech/Performance - 1991 Vette Idle Problem Failed Emissions - Hello I Have A 91 Vette with a Poor Idle And a Failed Emission test. replaced plugs and wires, fuel pressure is in check, replaced iac valve and Feb 7, 2008 · C4 Tech/Performance - 96 LT1 Running Rough at Idle - I have a 96 LT1 that is running rough at idle. When i try and cold start it, she doesn't wanna fire up. I'm stumped now. A intake manifold leak can cause a high idle. AT. C3 General - Fast idle problem - Hi guys, hoping someone can help with this issue. C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Data from the ECM will Nov 29, 2015 · C4 General Discussion - 1990 Tach Problem - I have a problem with my tachometer that I can't find a post to match. timing 3. Apr 25, 2003 · C4 Tech/Performance - Those with high idle problems, check this story out - I've been trying to get my '86 coupe to idle smoothly at 750 RPM like it is supposed to for the 2 years that I have had it. Apr 11, 2019 · C5 Tech - High idle problem. Thought I had it fixed, but after a few days driving it around town with no problems (no highway) but it has returned after a 30-40 mile Highway/freeway trip yesterday. And my ZR-1 likes to hover around 1,200-1,500 at idle (like at a stop light) for longer than it ever has even after it has been sufficiently warmed up. Just in the last few weeks I began to notice the following issues: (1) When accelerating under load regardless of gear, the engine will hiccup and bog pretty badly. Feb 10, 2015 · "Bella" - 2002 Z06 - Carrying on family tradition of Corvette ownership. It is not that hard to do just the 6 little screws at the bottom, have to remove air pump on driver side then replace nut clips onto the shroud opposite so screws go in from under the front where air comes in to cooling area, IE take nuts off shroud and put on piece that stays in car, you'll Jan 10, 2005 · C4 Corvette Forums. following this accurately will point you in the direction of where your high idle is caused. once in a while if it does ilde when you step Oct 6, 2006 · C5 Tech - Intermittent high idle - My Vette just developed an idle problem. I replaced the brake booster and had the same problem, so now I am looking into a vacuum issue. I followed the procedure indicated by the official manual to reset correct idle speed (slightly push the throttle, turn on the engine, let it run for 5 seconds. TPC 5. After reaching the 600 to 800 range Jun 19, 2002 · Has the idle screw on your throttle body been adjusted. A couple times when it has done this it stalled. Also when it warms up the idle rises ,the hotter it gets until it reaches operating temp it idles around 1400 to 1500 rpm. When cold out I set the choke with the accelerator and the car starts right up regardless of how long it has been sitting, and goes to fast idle. The car idled very high and was even going into third gear with my foot of off the peddle. We turn the idle screw and the idle does not go down the TPS drops and the IAC Apr 15, 2018 · C4 Tech/Performance - High idle - My 1990's idle is probably 1800. The last two days it has started wandering around, sometimes at 800, sometimes as high as 1400, sometimes at 950. intake leak 7. It will idle down after sitting for a few minutes, but still very annoying. I had set the low idle for the IAC and set TPS. Just replaced the EGR Temp Sensor, EGR gasket,Intake Air sensor, MAF Sensor, New Plenum gaskets, TB gasket. Sep 3, 2014 · C4 Tech/Performance - 1985 corvette tpi problems !!!! - I have a 1985 corvette that I just bought and it is giving me problems now. Aug 28, 2003 · C4 Tech/Performance - 89 TPI idle problems, please help - I just bought this 89 and it seemed to idle ok, just a little low. Jump to Latest You may have one or more sensors that are out of spec and causing your cold idle problem. I replaced the fuel pressure regulator and it fired right up. Jan 26, 2011 · C4 Tech/Performance - LT4 High Idle Problem - Ok car runs fine otherwise no performance issues or CEL. "Alexa" - 1985 Z51 - In memory of the last Corvette Dad owned. MAF sensor 8. I started having the idle problem when the temperatures started getting above 95 degrees Jun 29, 2005 · C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, still same high idle - 1500 RPM no other problems. - Hey everyone! Just opened up an account here after years of just reading through the threads. Scary to me as I am old school carburetor guy. Nov 4, 2009 · The recommended idle speed is only 450 rpm, so your car is idling pretty fast. These steps apply specifically to the 1985 model year, and it general to other years. Now it's happening just about every time I drive it. The thermostat stayed at 150 though. So I turned the idle up and got it idling fine. Update - Can't find anything leaking moisture on the optispark. I tried the procedure to set the TBI settings, grounded the ALDL to set the IACs, set the TPS. The car was idling at 1,500 rpm when I got it home. I have a 1988 corvette that surges at an idle and then dies. Could be as simple as a bad terminal or the crimp connection failed at the backside of the terminal for the IAC connection. temps get up to 235F within five to ten minutes or so. Sep 26, 2016 · C4 Tech/Performance - 89 Corvette high idle after reset IAC and TPS - Hi, guys, My 89 Corvette 6-speed car already 1000 mile after stock engine rebuild, it runs ok at first, but after a 300 miles road trip, the idle raise to 1300-1500, I already replace the IAC and adjust IAC and TPS. I do have a AFPR, and it is set to 42 lbs at May 27, 2012 · C4 Tech/Performance - high idle 1000-1200rpm - Hi got a 92 when I start it the idles is high at 1000-1200 rpm and wont settle after driving stays high any ideas. Any information helps. Are there any adjustments that can be done to change or Apr 16, 2003 · C4 Tech/Performance - Correct idle speed, LT1 - Can someone tell me what the correct idle speed is for an LT1? Mine is a 95 LT1, 6M. Any advice on getting it to Aug 28, 2005 · C4 Tech/Performance - Idle Problems 85 Corvette - OK Guys. The IAC motors are computer controlled and they SHOULD compensate for load changes when they occur. Apr 14, 2019 · C4 Tech/Performance - 1987 Corvette Surging Idle, No Response to Throttle, and Idling High in Park. So the 1985 4 plus 3 is rough idling at 1000 RPM. May 19, 2013 · Since buying my 1991 in September it has idled high. Once warmed up, the idle drops to around 600 in D. If there are no IAC counts showing on the scan tool but all other sensors feedback are OK, suspect broken wiring to the IAC. No codes. IAC valve has been checked and looks new/clean. - did a search,will take pics tomorrow Dec 21, 2009 · LewLinda1199 Standard Member Send Private Message Odenton, MD - USA Vette(s): 1987 T5 5 speed ,cast iron head motor (no history on this) Z-51 Bright red with gray leather interior Greenwood spoiler,Corvette Central muffler eliminators and American Racing 16" Gotti replicas. then at a red light it will go back down to the 800 rpm's. Gone but never forgotten. Aug 10, 2009 · To check for a cracked diaphram just spray some carb or TB cleaner under the EGR valve, if the idle picks up you have a cracked or leaking diaphram. Sometime when I really get on it and come to a stop its around 2000 or 3000 RPM. I installed the new PCV valve and the oscillating idle problem seemed to go away. When I first start my '87 it sits around 1,000 until it comes up to temp and then goes down to 600-700 when in park. I wonder. What I have gone through trying to fix it is beyond the patience most people have (including me). I adjusted the TPS to . It was boiling again, steam coming from both the reservoir and engine this time. One day I was Dec 14, 2010 · C4 Tech/Performance - Help me with my LT1 high idle, out of ideas - Back story: I bought a 92 in July and have been slowly bringing it back to working order. Never idles below 1600. I did a scan, I attempted to install a new TPS in case that might have been my idle problem. It is hard to slow for a corner at the track. 1K if you get a handle on the high idle problem let me know. Engine. Nov 18, 2009 · C4 Tech/Performance - Odd Acceleration Problem / High Idle - I recently removed my right exhaust manifold (thanks to a great Uncle) to replace the gaskets with a one-piece copper one. I just had the front seals replaced, water pump changed, radiator replaced, rotor cap and wires replaced. Oct 14, 2008 · Fuel injector's starting to go bad and dripping gas at an idle instead of a fine mist can cause this problem, Low fuel pressure or stopped up fuel filter. ive been checking for vacuum leaks, but cant seem to successfully find any. It had other idle issues besides this one (would not stay running when cold) but I think I tracked most of that down Sep 14, 2012 · New BBK 58ml has higher idle every thing done right but have to kick gas pedal down to bring rpms down 1988 corvette feels like your on crusie control driving,:smack anyone have this problem putting new 58 twin throttle body in? Thanks Mr. Of course May 22, 2017 · To clean cooling fins you have to remove the rad. I have been researching and searching the Forum's. I used the Sam Lam method to install the new injectors, and all new gaskets. Dec 14, 2010 · C4 Tech/Performance - Help me with my LT1 high idle, out of ideas - Back story: I bought a 92 in July and have been slowly bringing it back to working order. It ran great but idles a bit fast. Gave a little throttle and it woul run smooth at a normal idle Sep 14, 2008 · C4 Tech/Performance - Hunting, fluctuating, erratic idle - Hi I have an 86 Corvette and the idle seems to bounce all over the place. So let me just cut to the chase. But if I blip the throttle the car returns to her normal idle speed. This happens. Also, the idle speed adjustment screw seems to be frozen or maybe has lock-tite on it. If the car is in neutral, it has no issues going from idle to 4-5000 RPM. 54 volts. Upon installing it, the idle ran too high, around 1200 rpm or more. After a few minutes the idle starts to surge for a few seconds and returns to Aug 9, 2021 · 1996 Corvette Recalls, Technical Service Bulletins, & Maintenance Schedule. Sometimes it seems to run fine, other times it will idle about 2-300 rpm faster than normal with a misfire. Nov 7, 2001 · C4 ZR-1 Discussion - High Idle Problem on my 90 ZR-1 - This high idle problem is present on my ZR-1. org/epa-news --If you enjoyed be sure to leave a Jun 26, 2004 · C4 Tech/Performance - 92 LT1 - High Idle after IAC Replacement - I was experiencing a high idle (2,000 rpm) after the car was driven for a bit. Is the SES light on? Jan 18, 2017 · C6 Corvette General Discussion - throttle body problem - I just had the top of my throttle body cleaned by a mechanic and when he tried to reset the idle with his computer he couldn't set the idle. Also when I would hit the cruise button to drop a MPH, the car would slow and Dec 20, 2012 · C4 Tech/Performance - 1986 high idle - The car had a very high and surging idle. replaced the injectors, replaced some old brittle vac lines, and this made the car run and idle much better but instead of the 1200 rpm idle it still idles at 900. Here is what happens. In this year 1993 every C4 Corvette came with over 2 miles of wire if you stretched it all out and connected it together. But When stopped in traffic, the temperature goes up pretty fast on May 13, 2009 · C4 Tech/Performance - Idle Problem 96 LT1 - I have a 96 LT1 with an idle problem. in any event you will need to follow this to get yourself setup with the replacement parts. Dec 3, 2005 · C4 Tech/Performance - 1984 Corvette Cross Fire Idle Problem Cold - I recently purchased a 1984 Corvette 350/auto with the Z51 suspension. When it first cranking it ran smooth until it tried to settle down to an idle. Jump to Latest 19K views 13 May 1, 2013 · C4 Tech/Performance - 1994 LT1 Corvette With High Idle - Need additional Solutions, HELP!!!! - Hello everyone and thanks for taking the time to read my post :). When I?m idle, the car sounds too loud and almost like it?s reving itself like it wants to move forwards desperately. It seems to run fine when going do the road just crappy at idle. I would just shift into Neutral. when it is warm it idles ok until it put it in gear then Idle drops down to Feb 15, 2014 · C4 Tech/Performance - 1984 Crossfire has super high idle - I just inherited a 1984 Vette, and am new to this type of engine. 56 v and idle still high, between 1100-1500 when cold. In July my Vette started developing starting problems, ie it would take Feb 26, 2011 · C4 Tech/Performance - Hard start and high idle - This is becoming more frequent with my 85, and it used to only happen every once in awhile. Also when I would hit the cruise button to drop a MPH, the car would slow and then speed up even faster. i did go through the readjustment process of the accelerator screw, because the previous Apr 13, 2024 · C4 Tech/Performance - High idle - When I crank up car idles at about 13 to 14 then would drop down to 5 to 6 now it stays at 13 but drops to 8 when goes in gear thanks for any help Feb 19, 2019 · theres not a single problem on a C4 CORVETTE, that can't be diagnosed with a shop manual, fuel pressure gauge, multi meter, exhaust back pressure gauge/vacuum gauge and an accurate infrared temp gun, timing light, compression/leak down tester, basic mechanics tools, a set of jack stands and a floor jack. Actually 900 and drops 100 when I smach the steering wheel, eitherway a bit too high. TPS at 0. Click here for more info about our cars and autocrossing and other Corvette stuff. Timing 6 deg no EST 19 with EST connected. Right now it idles at about 900 RPM which seems a little high to me. The next day I started it and it was way too high. I have had a 1994 C4 (6 speed, 78,000 miles) for around 2 months now. Granted, it's very cold here at the moment, but the former owner told me about this. After driving a bit, I notice the Sep 18, 2011 · C4 Corvette General Discussion Rough idle when cold. Dec 30, 2023 · You will need to follow the minimum idle adjustment procedure for a c4. I finally purchased my 1st corvette at 58 years young. I havent driven it this summer, but this seems to be an ongoing problem. . still runs about 900-1100 at idle and engine hot. He says that this is a new problem that just showed up. Jul 26, 2020 · C4 Tech/Performance - 1986 C4 problems - I have a 1986 C4 Corvette, I had a problem where I'd be driving down the road and it would just die no warning , that was the ignition switch, now that I got that fixed the only way I can keep it running when I slow down is to adjust the idle up high, does anyone know what Jul 23, 2023 · Alright so I have a 1994 Base Model C4 as project car I've been working on for a while now. IAC 6. Then it got to where it wouldn't even stay running. One day I was Apr 19, 2011 · C4 Tech/Performance - 1984 corvette idle problem - PART 2 - Hello again, I am still having trouble lowering my idle speed on my 84 vette. The vacuum pump was cyling every 4-5 seconds for about a second. It tried idling at under 500 and stalled. I can't tell how much as the tac reads high but it's noticably faster than my buddy's 85. fuel pressure While all these might not make it a high idle, they will affect the idle Jan 8, 2006 · C4 Tech/Performance - '86 Idle and Stalling Problem - My 86 with 170k miles is having a problem at idle. My Car: 1994 Corvette C4 New water pump New thermometer Jul 2, 2005 · Check the spark plugs, spark plug gap, primary ignition circuit, high tension cables, distributor cap or ignition coil. It was high enough that the tranny was trying to go and I was holding the car back at traffic lights. If I put it in gear (drive/reverse) it drops down to around 750 or so. use 550rpm as the minimum with iac closed. Jan 27, 2021 · I have a problem with my C4 (1991 convertible l98 manual). Now it wants to hunt at Idle halfway warmed up. The car starts fine but idles at close to 1500rpm. 1989 c4 L98 Idle jumps to 2400 to 2800 at start up and then goes down to 600 to 800 after 20 to 30 seconds. 2 miles. C4 Corvette L98 Idle Problems (still) Jump to Latest 5. Did this just suddenly start or has it gradually gotten worse over time? The initial idle is way too high. Sometimes it will surge a little bit between 1600-2000 rpm. I took it out the other day and it ran great, the next day, I started it and the idle jumped to 4000 and stayed there. I was wondering About Some Options You Guys Might Know About. Most of the time in gear the Idle is at 650 to 700 RPM In gear it's a uto trans. between 190 - 200 degrees. On my 85 I noticed a few ways to play with the idle, here they are in random order; 1. Oct 15, 2002 · C4 Tech/Performance - 88 Vette--Starting, Idle Problems - Please forgive me, as this may be long. just over 2. Jun 3, 2023 · C4 General Discussion - 96 LT1 Surging idle - Hello All, I know there is a ton questions about the surging idle problem and while I have read a majority of the items and tried the solutions I still have the problem. The information contained on this page is for reference only. Now it will still idle high after being driven, but if i Nov 4, 2019 · C4 Tech/Performance - Stuck on high idle problem - '84 - Hi, I have an '84 Corvette and up until recently, it's been running very well although I haven't driven it much in the past year. "Desiree" - 1977 - Wife's car, with an attitude problem. When I looked his car over, I noticed a high idle even when warm (1100rpm). I have replaced the radiator with an Ecklers 3 Core Aluminum as well as the water pump. Followed the forum's advice and replaced the IAC, cleaned the throttle body and set IAC according to the manual. After it warms up and the carb plate opens all the way it stays on fast idle even after Jul 23, 2006 · After getting my car out of the shop still with the idling problem but no other issues, here's what has happened now. Jan 16, 2008 · C4 Tech/Performance - WinALDL and High Idle Problem - Car is a 1988 C4 with L98/TPI w/A4. What I have narrowed mine fown to is that it cuts off when I apply pressure to the barkes. I live where its hot and it can sometimes get up to 110 degrees. The temps have been colder lately here in NC. ECM as well . Feb 1, 2020 · C4 Tech/Performance - 1992 corvette high RPM at idle issue - HI everyone, i been having issues with high rpm at idle. around 1500 and after a minute or two it raises up to 1800. I removed the throttle body and i cleaned it. Mar 9, 2012 · Somewhere around 25 to 55 counts for the IAC with the engine fully warmed & at idle is normal. Sep 18, 2003 · C4 ZR-1 Discussion - high idle 90 zr1 - Mycar is idling at 2000rpms after driving2 blocks and it stays there until i shut it off. At startup it will be at about 1000 rpms. It wants to stay at around 950-1000 rpms and wont kick down. No apparent vacum leaks and already sprayed card cleaner around intake and throttle body with no Aug 14, 2011 · C4 Tech/Performance L98 Corvette and LT1 Corvette Technical Info, Internal Engine, External Engine 1994 high idle problem 1994 high idle problem. sema. Does Jul 15, 2008 · C4 Tech/Performance - c4 with high idle problems - Hi I have a 93 corvette,pretty much stock. BUT if I check the throttle body when this is occuring, it's against the idle screw, and not hanging open or binding. About 3 months later it started it again, but only slightly. Do you unplug the IAC and or the ECT? If someone has the correct procedure it would be greatly apprectiated. I've replaced the IAC valve and verified the throttle cable is not binding. Having a problem with the idle on my 1986 4 spd 350 TPI. It will be idling fine for about 30 seconds and then it will drop down to about 300-400 rpm. C4 Corvette Solving an engine problem(s) requires a light and a road map. vkexfge yvmcqz kxze xwd cgxpuc qugv azl zgcf qrlz qhqs jfqlwv sssygv uxrrro mntet aoax