C4 Death Trap
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
So I reset all my module codes, let my car run till it died out again, and rechecked the code list.
As follows
Module 1:
C31
C33
C35
C37
Module 4.0
- - -
Module 9.0
H64
Any thoughts?
I believe the CCM Module 1 codes arent indicating anything since before I reset them they were fine. It might just be from a weak battery. However, if im not mistaken, I think H64 indicates lean 02 sensor, correct?
As follows
Module 1:
C31
C33
C35
C37
Module 4.0
- - -
Module 9.0
H64
Any thoughts?
I believe the CCM Module 1 codes arent indicating anything since before I reset them they were fine. It might just be from a weak battery. However, if im not mistaken, I think H64 indicates lean 02 sensor, correct?
Last edited by Mason8383; Mar 2, 2021 at 10:04 PM.
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
So after the reset, my car shut off in park after I slightly gave it gas. It showed H64. Now, I restarted the car and it wouldn't shut off at all. I even took it around the block for around 10 mins and hit a few hole punches. It will not turn off. Is there any way the o2 sensors can act up and run normally again? Also, my car runs really rich, so im leaning toward o2s.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
So after the reset, my car shut off in park after I slightly gave it gas. It showed H64. Now, I restarted the car and it wouldn't shut off at all. I even took it around the block for around 10 mins and hit a few hole punches. It will not turn off. Is there any way the o2 sensors can act up and run normally again? Also, my car runs really rich, so im leaning toward o2s.
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
I think they may be original 02s, my 94 has a114k miles on it, only the 2nd owner. If not the 02s, could it then move to the fuel system? It idles fine and doesn't stumble, but once it gets a little gas or at idle, it shuts off.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
Could what move to the fuel system? As to it idling fine, I really don't know what that means. If it is a SOTP dyno thing, I'd definitely be more suspicious. IMO, the cars are much better at hiding things by making adjustments than they used to be so it is harder to spot an issue. If you mean it idles fine by reading the data from a scanner, that might be another issue.
Last edited by aklim; Mar 2, 2021 at 11:57 PM.
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
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
I'd definitely toss the O2 especially in the upstream part. People usually ASSume that the O2 is good till it fails. I believe they get old and lazy before they fail usually. That messes up your mileage, at least.
Could what move to the fuel system? As to it idling fine, I really don't know what that means. If it is a SOTP dyno thing, I'd definitely be more suspicious. IMO, the cars are much better at hiding things by making adjustments than they used to be so it is harder to spot an issue. If you mean it idles fine by reading the data from a scanner, that might be another issue.
Could what move to the fuel system? As to it idling fine, I really don't know what that means. If it is a SOTP dyno thing, I'd definitely be more suspicious. IMO, the cars are much better at hiding things by making adjustments than they used to be so it is harder to spot an issue. If you mean it idles fine by reading the data from a scanner, that might be another issue.
Team Owner
Joined: Jul 2004
Posts: 28,475
Likes: 3,291
From: Hartford WI
I see what you mean about the 02s, ill get them replaced. When I said move up to the fuel system, I meant can the o2 sensors code that popped up also include fuel system failures? When I mean it idles fine, it starts up without hesitation, sits at a steady rpm, and does not become sluggish at a stop or when I take off. Nothing indicated bad air or fuel ratio to me, aside from the fact that it runs rich.
Drifting
Joined: Apr 2020
Posts: 1,925
Likes: 610
From: Orange, CA
That is true, and I will order that code reader. However. I did short pin 4 and 12 and found my code reads on the gauge panel which goes as follows:
Module 1:
C12
Module 9:
H64
H72
H73
Module A:
C51
C52
H24
H42
H51
H52
H61
H62
H71
H76
If anyone can help point me in the right direction about these I'd appreciate it. I can go down the list to figure them out, but if anyone has some knowledge on this it wouldn't hurt while I'm doing it.
Module 1:
C12
Module 9:
H64
H72
H73
Module A:
C51
C52
H24
H42
H51
H52
H61
H62
H71
H76
If anyone can help point me in the right direction about these I'd appreciate it. I can go down the list to figure them out, but if anyone has some knowledge on this it wouldn't hurt while I'm doing it.
Android or fruit phone? If android, maybe THIS might help? It scans data and is easy to use. At least, it is for my 91.
Since it's a 94, if you want to DIY, you could always try datalogging from it using a laptop, see if you can capture data from the car when it dies to see what exactly is dying. If you want to explore that option, here's the cable you'll want to grab: http://aldlcable.com/products/aldlobd2u.asp
And here's the software (free): http://fbodytech.com/eehack-2/download-eehack/
And here's the software (free): http://fbodytech.com/eehack-2/download-eehack/
Also a failing O2 or coolant temp sensor won't kill the car. It could make the car run poorly, but it won't completely kill it.
So I reset all my module codes, let my car run till it died out again, and rechecked the code list.
As follows
Module 1:
C31
C33
C35
C37
Module 4.0
- - -
Module 9.0
H64
Any thoughts?
I believe the CCM Module 1 codes arent indicating anything since before I reset them they were fine. It might just be from a weak battery. However, if im not mistaken, I think H64 indicates lean 02 sensor, correct?
As follows
Module 1:
C31
C33
C35
C37
Module 4.0
- - -
Module 9.0
H64
Any thoughts?
I believe the CCM Module 1 codes arent indicating anything since before I reset them they were fine. It might just be from a weak battery. However, if im not mistaken, I think H64 indicates lean 02 sensor, correct?
The discrepancy in codes seems to indicate some serious electrical problems with the car. If you want to rule out the battery, make sure it's nice and solid at 12V, wipe all the codes again, and pull them again.
Last edited by Nomake Wan; Mar 3, 2021 at 12:42 AM.
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
Module 1 is the CCM and indicates no codes. Module 9 is the ABS/ASR and indicates TPS signal failure, serial link data fault, and spark retard monitoring fault. Where is Module 4?
As stated multiple times, this USB cable with a laptop is far superior than any standalone scan tool or cell phone for a 94-95 Corvette.
Also a failing O2 or coolant temp sensor won't kill the car. It could make the car run poorly, but it won't completely kill it.
Incorrect. Module 9 H64 is "ABS/ASR TPS signal failure." Your new CCM failures are very peculiuar. Either they're CCM internal failures or you have some bad mojo going on inside the dash. I wonder if it had to do with your airbag system having deployed at some point (according to the codes you had before you erased them).
The discrepancy in codes seems to indicate some serious electrical problems with the car. If you want to rule out the battery, make sure it's nice and solid at 12V, wipe all the codes again, and pull them again.
As stated multiple times, this USB cable with a laptop is far superior than any standalone scan tool or cell phone for a 94-95 Corvette.
Also a failing O2 or coolant temp sensor won't kill the car. It could make the car run poorly, but it won't completely kill it.
Incorrect. Module 9 H64 is "ABS/ASR TPS signal failure." Your new CCM failures are very peculiuar. Either they're CCM internal failures or you have some bad mojo going on inside the dash. I wonder if it had to do with your airbag system having deployed at some point (according to the codes you had before you erased them).
The discrepancy in codes seems to indicate some serious electrical problems with the car. If you want to rule out the battery, make sure it's nice and solid at 12V, wipe all the codes again, and pull them again.
Last edited by Mason8383; Mar 3, 2021 at 01:05 AM.
Advanced
Joined: Dec 2020
Posts: 64
Likes: 2
From: florida
I would spend some quality time going thru the wiring around the engine and checking your ground points. Check the harness that runs by the right valve cover and goes down to the opti. That harness does alot of things. Get a multi meter and check for continuity with your wires and grounds. Do what Nomake said. Get the EEhack and the cable. Good luck..
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
I would spend some quality time going thru the wiring around the engine and checking your ground points. Check the harness that runs by the right valve cover and goes down to the opti. That harness does alot of things. Get a multi meter and check for continuity with your wires and grounds. Do what Nomake said. Get the EEhack and the cable. Good luck..
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
I reset my codes today and restarted my car. A new set of codes popped up. As follows:
Module 1:
C12 (clear again)
Module 4:
H82
Module 9:
- - -
Module A:
C51
C52
C71
C76
H24
H42
H51
H52
H61
H62
H71
H76
a bit confused on why it would throw the old history codes from Mod A at me again. What could this signal? Also, H82 is new, have not seen it before.
Module 1:
C12 (clear again)
Module 4:
H82
Module 9:
- - -
Module A:
C51
C52
C71
C76
H24
H42
H51
H52
H61
H62
H71
H76
a bit confused on why it would throw the old history codes from Mod A at me again. What could this signal? Also, H82 is new, have not seen it before.
Last edited by Mason8383; Mar 3, 2021 at 12:39 PM.
Drifting
Joined: Aug 2009
Posts: 1,972
Likes: 243
Wow man, you really need to datalog the thing, that will show you what is changing in the moment that it quits. Intermittent problems suck, the car is trying to tell you what’s wrong you just need the right setup to see that info. Otherwise we’re just taking guesses with you and you might end up replacing good parts. Seriously, cable is a small investment. Software free. Have an old laptop?
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
Wow man, you really need to datalog the thing, that will show you what is changing in the moment that it quits. Intermittent problems suck, the car is trying to tell you what’s wrong you just need the right setup to see that info. Otherwise we’re just taking guesses with you and you might end up replacing good parts. Seriously, cable is a small investment. Software free. Have an old laptop?
Drifting
Joined: Apr 2020
Posts: 1,925
Likes: 610
From: Orange, CA
I reset my codes today and restarted my car. A new set of codes popped up. As follows:
Module 1:
C12 (clear again)
Module 4:
H82
Module 9:
- - -
Module A:
C51
C52
C71
C76
H24
H42
H51
H52
H61
H62
H71
H76
a bit confused on why it would throw the old history codes from Mod A at me again. What could this signal? Also, H82 is new, have not seen it before.
Module 1:
C12 (clear again)
Module 4:
H82
Module 9:
- - -
Module A:
C51
C52
C71
C76
H24
H42
H51
H52
H61
H62
H71
H76
a bit confused on why it would throw the old history codes from Mod A at me again. What could this signal? Also, H82 is new, have not seen it before.
There are some very serious electrical problems on your car, it would appear. As an earlier poster said, it makes me wonder if the shop that was doing work on your car failed to reconnect things correctly. Ground straps are especially important on our cars since so much of the car is fiberglass rather than metal.
Thread Starter
Intermediate
Joined: Oct 2020
Posts: 49
Likes: 6
Shorting those pins only tells you trouble codes (and lets you reset trouble codes, and cycle some CCM inputs, and check some CCM inputs and outputs). Connecting a laptop lets you do all of that as well as log realtime data from the car (and reprogram the PCM but we won't bother with that right now). It's hard to explain just how much more useful a laptop with a cable is than literally any other electronic tool for a 94-95 Corvette.
Module A seems to very much think that your car has been in an accident severe enough to pop the airbags. Module 4 H82 is Transmission 1-2 Shift Solenoid Circuit failure.
There are some very serious electrical problems on your car, it would appear. As an earlier poster said, it makes me wonder if the shop that was doing work on your car failed to reconnect things correctly. Ground straps are especially important on our cars since so much of the car is fiberglass rather than metal.
Module A seems to very much think that your car has been in an accident severe enough to pop the airbags. Module 4 H82 is Transmission 1-2 Shift Solenoid Circuit failure.
There are some very serious electrical problems on your car, it would appear. As an earlier poster said, it makes me wonder if the shop that was doing work on your car failed to reconnect things correctly. Ground straps are especially important on our cars since so much of the car is fiberglass rather than metal.