1982 corvette fuel injector help
Thread Starter
Advanced
Joined: Jul 2019
Posts: 59
Likes: 3
1982 corvette fuel injector help
Hello, so I got an 82 with CFI. Ever since I got the car it’s been having troubles. One of those has been a constant slight missfire and it runs rough when warm and idling. I don’t get any codes and when I get up to speed, it does just fine.
I checked the injectors to see if there was any issues there. I saw that the rear injector (closest to the driver) has got these really small drips coming out of the injector head every time it pulses and it’s spraying alittle off.
do you think this could cause the missfire and running rough? I also thing the ignition coil may be bad which isn’t helping. I’ve redone the entire ignition system besides the coil
I checked the injectors to see if there was any issues there. I saw that the rear injector (closest to the driver) has got these really small drips coming out of the injector head every time it pulses and it’s spraying alittle off.
do you think this could cause the missfire and running rough? I also thing the ignition coil may be bad which isn’t helping. I’ve redone the entire ignition system besides the coil
Last edited by Kacey1; May 18, 2021 at 05:10 AM.
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Two things...fuel and balance. Take a timing light and point it at the injector spray cone. You will be able to see how the injector spray pattern is looking and should be a nice even pattern. Could be a dirty injector or something else. Also, TB balance IS real important on these motors along with fuel pressure, FP should be at 13psi for maximum potential of the motor.
Drifting
Joined: Aug 2019
Posts: 1,339
Likes: 225
Get a scan tool to monitor block learn values. If the value is below 128, then the computer is cutting back on fuel to compensate for the drippy injector. In that case, all of the plugs might be darker than normal. If it's only one or 2 plugs, then I would lean to ignition like wires, or even a bad plug.
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Get a scan tool to monitor block learn values. If the value is below 128, then the computer is cutting back on fuel to compensate for the drippy injector. In that case, all of the plugs might be darker than normal. If it's only one or 2 plugs, then I would lean to ignition like wires, or even a bad plug.
Drifting
Joined: Aug 2019
Posts: 1,510
Likes: 498
the Snap On Brick , Pro Link and the GM scan tool all read Block learn . Block learn won't move on open loop but is active in closed loop , you can also compare the long term and short term numbers at idle and while running 2500 rpm , numbers equal out close at 2500 rpm is usually a vacuum leak
Melting Slicks
Joined: May 2021
Posts: 2,274
Likes: 1,317
From: Fleming Island, FL
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
Top 10 Most Expensive Corvettes Ever Sold on Bring A Trailer
Brett Foote
10 Things Every Corvette Owner Needs (2026 Edition)
Michael S. Palmer
8 Most "Only Corvette Owners Understand" Quirks and Problems
Pouria Savadkouei
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
Drifting
Joined: Aug 2019
Posts: 1,339
Likes: 225
I would stick with Snap on, I've had a few of their scanners, and there's a lot of hardware available even on ebay.
Any of the Snap on scanners are backward compatible, so if you know someone who has one. or someone who's selling one, you don't have to be picky. Just make sure that it has the correct cable and connector, and you're good to go.
Any of the Snap on scanners are backward compatible, so if you know someone who has one. or someone who's selling one, you don't have to be picky. Just make sure that it has the correct cable and connector, and you're good to go.
Last edited by Mrvettenick; May 18, 2021 at 12:36 PM.
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
I guess I should have clarified my earlier post a bit, my bad. I meant, which scanner that "doesn't cost an arm or a leg". Snap-On is way too high to just troubleshoot this issue IMO. There are simpler and cheaper ways to do this without spending your kids college money on a scanner. I think that a simple look at the injector flow/spray will tell you a lot. If it's dripping while spraying or dribbling after turning off the motor, the small o-ring in the bottom of the pod is bad or injector isn't spraying properly, dirty...again, you will be able to see that with a simple timing light. It may have ECM injector driver issues? I don't need that equipment since I'm using the EBL and it tells me a lot of what's going on with the motor/ECM, but a stock motor won't have that benefit unless they use a HAM board with the EBL Flash II. 
Last edited by Buccaneer; May 18, 2021 at 07:26 PM.
Drifting
Joined: Aug 2019
Posts: 1,339
Likes: 225
I guess I should have clarified my earlier post a bit, my bad. I meant, which scanner that "doesn't cost an arm or a leg". Snap-On is way too high to just troubleshoot this issue IMO. There are simpler and cheaper ways to do this without spending your kids college money on a scanner. I think that a simple look at the injector flow/spray will tell you a lot. If it's dripping while spraying or dribbling after turning off the motor, the small o-ring in the bottom of the pod is bad or injector isn't spraying properly, dirty...again, you will be able to see that with a simple timing light. It may have ECM injector driver issues? I don't need that equipment since I'm using the EBL and it tells me a lot of what's going on with the motor/ECM, but a stock motor won't have that benefit unless they use a HAM board with the EBL Flash II.
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Define arm and a leg. Anyone who wants to perform diagnostics needs to have one. In this situation the mT2500 can be had for a reasonable price. The OP is complaining of a misfire, Is it fuel or ignition related? Outside of a drippy injector, that's all you have to go on. Everyone has their own approach. .
Drifting
Joined: Aug 2019
Posts: 1,510
Likes: 498
I bought my Snap On MT2500 aka Brick from ebay for 250.00 and it has all the cartidges and connectors plus had all the Ford and Chrysler too , the Pro Link was around 500.00 and GM Tech 1 was 550.00 but I bought a real nice one .
Melting Slicks
Joined: Feb 2017
Posts: 3,232
Likes: 1,232
From: PHX AZ
clever ****
Two things...fuel and balance. Take a timing light and point it at the injector spray cone. You will be able to see how the injector spray pattern is looking and should be a nice even pattern. Could be a dirty injector or something else. Also, TB balance IS real important on these motors along with fuel pressure, FP should be at 13psi for maximum potential of the motor.
Safety Car
Joined: Nov 2005
Posts: 3,532
Likes: 1,185
From: Arizona - If you don’t know CFI, STOP proliferating the myths around it...
Well, shizzle my nizzle.