But also could be a dying ICM.
was fine when i put it away
Thread Starter
4th Gear
Joined: Jan 2012
Posts: 4
Likes: 0
was fine when i put it away
need some help on a 94lt1.. my good freind,who owns a few corvettes, said try to here,says you vette owners know more about the lt1s i have a 94 lt1,, put the car away monthand half ago,, 57168 original miles,ran fine , only upgrade was a cold air kit.i did some rear susp upgrades 2 weeks ago, when i took the car ou last weekend 40s and no snow for a test ride ran fine,, when i went about 2 miles and hit a nice piece of road i nailed it about 5000 rpms, started to backfire through the throttle body,, i slowed down turned around and was heading back,, about 2-3000 rpm you could feel a lose of power and detonation,, got back to the garage and in pack you could hear it miss and detonate in park.no check engine light, but tired to pull a code,,this thing wont give one up,,use that little scanner,that just jumps the pins and all it does is turn the cooling fan on,anyway, waited about 10 minutes, started it up,didnt sound as bad and no detonation,, waited another 15 minutes and it sounded fine,normal, what do you think? tune up? comp? maf? any help would be great
Race Director
Joined: Apr 2003
Posts: 17,700
Likes: 1,667
From: moraga ca
Not sure what is wrong with your car, but if it wasn't started in a month and a half and you ran it for 2 miles in 40 degree temperature, your oil temperature was probably all the way up to 45 degrees when you nailed the throttle. Motors don't like to be revved when the oil is thick. It probably won't last another 57000 miles.
Drifting
Joined: Jun 2010
Posts: 1,853
Likes: 8
From: Westerly RI
The Opti or the ICM can be failing without setting any codes. If the missing happens only when the engine is warm, you would lean towards the ICM. If it misses cold or warm, more likely the Opti.
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
10 Reasons the C6 Z06 is Still A Performance Benchmark After 20 Years
Joe Kucinski
How Much Horsepower Every Corvette Engine "LOST" in 1972
Joe Kucinski
Top 10 DOs and DON'Ts for Protecting Your Convertible Top!
Michael S. Palmer
Top 10 Most Explosive Corvettes Ever Made: Power-to-Weight Ratio Ranked!
Joe Kucinski
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Safety Car
Joined: Aug 2002
Posts: 3,842
Likes: 230
From: SANTA CRUZ CA
Instructor
Joined: Apr 2011
Posts: 208
Likes: 0
From: Trophy Club Texas
What concerns me is you say NO Codes, but the fan comes in with aldl jumpered and you are waiting 10 mins with no results.
Couple basic questions... When you have the engine off but ignition in on position does the SES light come on as it should? Also, when you jumper the aldl pins do you at least get code 12 like you should? If you are not getting either of those... I would check the bulb for the SES, then check for codes again.
If the bulb is good but no code 12, get the FSM out and start running through the troubleshooting charts. My FSM is for a 91 or I would offer more help.
Couple basic questions... When you have the engine off but ignition in on position does the SES light come on as it should? Also, when you jumper the aldl pins do you at least get code 12 like you should? If you are not getting either of those... I would check the bulb for the SES, then check for codes again.
If the bulb is good but no code 12, get the FSM out and start running through the troubleshooting charts. My FSM is for a 91 or I would offer more help.
Thread Starter
4th Gear
Joined: Jan 2012
Posts: 4
Likes: 0
yes the ses light comes on,but no code 12 , all it did once was flash like crazey,had a problem 3 months ago trying to get a code,a freind of mine said he got the code ,dont know how,, something about he went through the console? anyway we found a bad 02 sensor and replaced them all.
Burning Brakes
Joined: Mar 2004
Posts: 1,108
Likes: 4
From: Plano Texas
formula94, What you are describing could be a fuel starvation problem. It sounds like your car may be running lean on the high end. When that happens it will backfire and then settle back down at lower RPMs. When is the last time you changed your fuel filter? Have you ever changed out the fuel sock on the end of the fuel pump? Either of these, or even a worn out fuel regulator on the fuel rail, will cause a lean condition that will starve the engine of fuel. I would check your fuel filter first. I'll bet that is your problem.
Good luck. Mark
Good luck. Mark
Drifting
Joined: Jun 2010
Posts: 1,853
Likes: 8
From: Westerly RI
yes the ses light comes on,but no code 12 , all it did once was flash like crazey,had a problem 3 months ago trying to get a code,a freind of mine said he got the code ,dont know how,, something about he went through the console? anyway we found a bad 02 sensor and replaced them all.
