Code "H61" on a 1995 (?) Help!
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From: Lynn Haven, FL
Code "H61" on a 1995 (?) Help!
Yes, I received a Code "H61" when I retrieved codes via the paperclip method. There is NOT a code 61 in ANY of my manuals, in any of the forum threads, or even in any of the "F" Body websites. Yes, I am sure of the number - even checked it twice (like Santa does his list). Does anyone have a clue?
Prior to struggling back to the garage, heavy black soot was coming out of the tailpipe and covering the entire rear of the car. I checked a few fittings and generally shined the flashlight around (like THAT was gonna help) . . . Now it runs fine.
C'mon guys/gals - someone has to know what's going on here . . . lol
Thanks in advance, Gary
Prior to struggling back to the garage, heavy black soot was coming out of the tailpipe and covering the entire rear of the car. I checked a few fittings and generally shined the flashlight around (like THAT was gonna help) . . . Now it runs fine.
C'mon guys/gals - someone has to know what's going on here . . . lol
Thanks in advance, Gary
Le Mans Master
Joined: Feb 2006
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From: Louisiana
I did an advanced search and could not find a DTC #61 for the 94-95 Corvette. What module was it found in (1,4,9) and what was your prodecure of pulling the codes?
From the description, it sounds like a O2 sensor code.
From the description, it sounds like a O2 sensor code.
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From: Lynn Haven, FL
Thanks for the reply. My '95 has the 16 pin ALDL and I paperclipped #4 and #12 terminals, per research in various C-4 threads. There were four codes set: H64 in Module 4; and in module "A", H24, H61, and H62. I am not sure what Module "A" is, but that was the read-out on the dash display. I even ran the sequence again to make sure.
Now, this is the first time I have pulled codes because it is the first time I have had ANY problem with this pristine 47,000 mile car. So, the other codes may be ancient history. But factoring in the sputtering and smoking, I guessed that maybe the O2 sensor was a culprit. But I could not find an H61 code anywhere.
Thanks, Gary
Now, this is the first time I have pulled codes because it is the first time I have had ANY problem with this pristine 47,000 mile car. So, the other codes may be ancient history. But factoring in the sputtering and smoking, I guessed that maybe the O2 sensor was a culprit. But I could not find an H61 code anywhere.
Thanks, Gary
Le Mans Master
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From: Louisiana
You might want to disconnect the neg cable on the battery for ~15 sec to clear the codes. Start the engine and go for a short drive and pull the codes again. See what shows up.
You are correct. The 94-95 are OBDI with the 16 pin ALDL and you used the correct terminals to pull codes. The 96 changed to OBDII and still has the 16 pin ALDL. I haven't seen a module "A" before in any refrence either. The H means it's a history code, and a C means it is a current code.
If the black soot was coming from just one side of the exhaust, I'm betting one of the O2's has died. Just can't do much with a code that doesn't exist on paper.
You are correct. The 94-95 are OBDI with the 16 pin ALDL and you used the correct terminals to pull codes. The 96 changed to OBDII and still has the 16 pin ALDL. I haven't seen a module "A" before in any refrence either. The H means it's a history code, and a C means it is a current code.
If the black soot was coming from just one side of the exhaust, I'm betting one of the O2's has died. Just can't do much with a code that doesn't exist on paper.
Safety Car
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From: VA
Not a ZR1 is it? A quick search shows that they have a DTC 61.
Your description of the driveability problems does not sound like an O2 problem, because an O2 failure that causes problems that bad will throw it into open loop and the problems will then clear up.
But given that it is throwing a mystery code, we can't assume that the PCM is operating correctly, so this may not hold true in your case.
Getting a scanner on it to see what the O2s are doing would be a good idea. Short of that you can unplug the front O2s and see if it improves.
Your description of the driveability problems does not sound like an O2 problem, because an O2 failure that causes problems that bad will throw it into open loop and the problems will then clear up.
But given that it is throwing a mystery code, we can't assume that the PCM is operating correctly, so this may not hold true in your case.
Getting a scanner on it to see what the O2s are doing would be a good idea. Short of that you can unplug the front O2s and see if it improves.
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From: Lynn Haven, FL
Vis: Thanks. No, sadly not a ZR-1. I was under the impression that a failed O2 would actually cause a lean versus a rich condition.
RTT: I think I will follow that plan and then pull codes afterward. Worst that can happen is that I will lose my radio presets, lol. I recall seeing the "A" module reference somewhere, but I have not been able to find it.
Rest assured all that I will post my results here and the description of the "H61" code, and the "A" module. This is totally weird, but like I said, today the car ran fine with no sooty exhaust. Gremlins maybe?
Thanks again to both of you. Gary
RTT: I think I will follow that plan and then pull codes afterward. Worst that can happen is that I will lose my radio presets, lol. I recall seeing the "A" module reference somewhere, but I have not been able to find it.
Rest assured all that I will post my results here and the description of the "H61" code, and the "A" module. This is totally weird, but like I said, today the car ran fine with no sooty exhaust. Gremlins maybe?
Thanks again to both of you. Gary
Melting Slicks
Joined: Feb 1999
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From: sonoma ca
Vis: Thanks. No, sadly not a ZR-1. I was under the impression that a failed O2 would actually cause a lean versus a rich condition.
RTT: I think I will follow that plan and then pull codes afterward. Worst that can happen is that I will lose my radio presets, lol. I recall seeing the "A" module reference somewhere, but I have not been able to find it.
Rest assured all that I will post my results here and the description of the "H61" code, and the "A" module. This is totally weird, but like I said, today the car ran fine with no sooty exhaust. Gremlins maybe?
Thanks again to both of you. Gary
RTT: I think I will follow that plan and then pull codes afterward. Worst that can happen is that I will lose my radio presets, lol. I recall seeing the "A" module reference somewhere, but I have not been able to find it.
Rest assured all that I will post my results here and the description of the "H61" code, and the "A" module. This is totally weird, but like I said, today the car ran fine with no sooty exhaust. Gremlins maybe?
Thanks again to both of you. Gary
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From: Lynn Haven, FL
Thanks again to all. I located the "A" module reference in another Forum thread:
Finally, Module "A", the DERM (Dynamic Energy Control Module --- the air bag control module) will be requested to show any codes.
My air bag light comes on occasionally, so that may be it.
Bottom line: none of the codes that I retrieved relate to the condition that I encountered the other day - sputtering and heavy black sooty exhaust. Plus, my "check engine" light came on a few times and then went away. Car runs OK now. Strange?
I may have to dig deeper - maybe even call Gordon Killebrew for answers, lol.
Thanks again, and stay tuned. Gary
Finally, Module "A", the DERM (Dynamic Energy Control Module --- the air bag control module) will be requested to show any codes.
My air bag light comes on occasionally, so that may be it.
Bottom line: none of the codes that I retrieved relate to the condition that I encountered the other day - sputtering and heavy black sooty exhaust. Plus, my "check engine" light came on a few times and then went away. Car runs OK now. Strange?
I may have to dig deeper - maybe even call Gordon Killebrew for answers, lol.
Thanks again, and stay tuned. Gary
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From: Lynn Haven, FL
In re-reading RRT's reply, the black soot came from BOTH exhaust pipes, leading me to believe that not one O2 sensor is bad. Moving up the chain, something caused this over-rich condition (like when a power valve sticks on an old Quadra-Jet) then it went away, but no code was set.
To erase the codes, all I do is disconnect the negative battery cable for ~15 sec - that simple???
To erase the codes, all I do is disconnect the negative battery cable for ~15 sec - that simple???
Le Mans Master
Joined: May 2005
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From: Queensland, AUSTRALIA
In re-reading RRT's reply, the black soot came from BOTH exhaust pipes, leading me to believe that not one O2 sensor is bad. Moving up the chain, something caused this over-rich condition (like when a power valve sticks on an old Quadra-Jet) then it went away, but no code was set.
To erase the codes, all I do is disconnect the negative battery cable for ~15 sec - that simple???
To erase the codes, all I do is disconnect the negative battery cable for ~15 sec - that simple???
