catalytic converter problem
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Burning Brakes
Joined: Jun 2008
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From: Beavercreek Ohio Currently own: 1958 Silver Blue Corvette & 1969 Riverside Gold Corvette Coupe
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catalytic converter problem
So I was out for a short drive this weekend and for the last 1/2 mile before I got home, my car was running REALLY rough. I could definitely smell a rotten egg odor coming from the exhaust.
I'm guessing it's one or both of the catalytic converters.
Need some advice: I don't want to replace both of them if only one is bad. How can you tell which one is clogged? Can they be unclogged or gotta be replaced? Thanks in advance!
I'm guessing it's one or both of the catalytic converters.
Need some advice: I don't want to replace both of them if only one is bad. How can you tell which one is clogged? Can they be unclogged or gotta be replaced? Thanks in advance!
Le Mans Master
Joined: Sep 2014
Posts: 5,278
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From: Kelowna BC
If one or both cats are actually done, you should be getting codes. P0420 (left/drivers) or P0421 (passenger side) are the codes IIRC. That is unless you've had the rear sensors opted out.
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Thread Starter
Burning Brakes
Joined: Jun 2008
Posts: 916
Likes: 1,207
From: Beavercreek Ohio Currently own: 1958 Silver Blue Corvette & 1969 Riverside Gold Corvette Coupe
2025 C1 of the Year - Unmodified Finalist
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BTW, I was also getting the 'check engine' light. After pulling the codes I started the vette a ran it for about 5 minutes - runs OK but still getting the 'check engine' light.
Pulled the codes. There were 8 each for LDCM and RDCM - not listing those because I've been having door lock problems for awhile and I think that's unrelated.
Besides those here are the remaining codes:
10-PCM P0300 H C - Engine Misfire Detected
B0-RFA U1016 H - PCM loss of comm
B0-RFA U1064 H - BCM loss of comm
B0-RFA U1096 H - IPC loss of comm
B0-RFA U1255 H - Serial data line malfunction
B0-RFA C2105 H - Right front TPM sensor malfunction
99-HVAC B0367 - Right actuator feedback open
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Le Mans Master
Joined: Sep 2013
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From: Wisconsin
Gotta admit I haven't had it over 100 for awhile
BTW, I was also getting the 'check engine' light. After pulling the codes I started the vette a ran it for about 5 minutes - runs OK but still getting the 'check engine' light.
Pulled the codes. There were 8 each for LDCM and RDCM - not listing those because I've been having door lock problems for awhile and I think that's unrelated.
Besides those here are the remaining codes:
10-PCM P0300 H C - Engine Misfire Detected
B0-RFA U1016 H - PCM loss of comm
B0-RFA U1064 H - BCM loss of comm
B0-RFA U1096 H - IPC loss of comm
B0-RFA U1255 H - Serial data line malfunction
B0-RFA C2105 H - Right front TPM sensor malfunction
99-HVAC B0367 - Right actuator feedback open
BTW, I was also getting the 'check engine' light. After pulling the codes I started the vette a ran it for about 5 minutes - runs OK but still getting the 'check engine' light.
Pulled the codes. There were 8 each for LDCM and RDCM - not listing those because I've been having door lock problems for awhile and I think that's unrelated.
Besides those here are the remaining codes:
10-PCM P0300 H C - Engine Misfire Detected
B0-RFA U1016 H - PCM loss of comm
B0-RFA U1064 H - BCM loss of comm
B0-RFA U1096 H - IPC loss of comm
B0-RFA U1255 H - Serial data line malfunction
B0-RFA C2105 H - Right front TPM sensor malfunction
99-HVAC B0367 - Right actuator feedback open
Thread Starter
Burning Brakes
Joined: Jun 2008
Posts: 916
Likes: 1,207
From: Beavercreek Ohio Currently own: 1958 Silver Blue Corvette & 1969 Riverside Gold Corvette Coupe
2025 C1 of the Year - Unmodified Finalist
2024 C1 of the Year Finalist - Unmodified
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Just wanted to follow up on this - the symptoms were a 'check engine' light and the vette was running REALLY rough. I could definitely smell a rotten egg odor coming from the exhaust and I was concerned about having to replace one or both of the catalytic converters. All 8 spark plugs were replaced 6 months ago.
After getting a complete diagnosis it turns out that it had 2 bad spark plug wires (should have replaced them when the plugs were switched out) and it had 3 bad ignition coils. So it was just dumping unburned fuel into the exhaust system - not good.
In the end with all new plugs, wire, and coils it runs like corvette should! Thanks to all for your advice
After getting a complete diagnosis it turns out that it had 2 bad spark plug wires (should have replaced them when the plugs were switched out
) and it had 3 bad ignition coils. So it was just dumping unburned fuel into the exhaust system - not good. In the end with all new plugs, wire, and coils it runs like corvette should! Thanks to all for your advice
Team Owner
Joined: May 2001
Posts: 87,314
Likes: 1,585
From: Western NY
Just wanted to follow up on this - the symptoms were a 'check engine' light and the vette was running REALLY rough. I could definitely smell a rotten egg odor coming from the exhaust and I was concerned about having to replace one or both of the catalytic converters. All 8 spark plugs were replaced 6 months ago.
After getting a complete diagnosis it turns out that it had 2 bad spark plug wires (should have replaced them when the plugs were switched out) and it had 3 bad ignition coils. So it was just dumping unburned fuel into the exhaust system - not good.
In the end with all new plugs, wire, and coils it runs like corvette should! Thanks to all for your advice
After getting a complete diagnosis it turns out that it had 2 bad spark plug wires (should have replaced them when the plugs were switched out
) and it had 3 bad ignition coils. So it was just dumping unburned fuel into the exhaust system - not good. In the end with all new plugs, wire, and coils it runs like corvette should! Thanks to all for your advice
Le Mans Master
Joined: Sep 2014
Posts: 5,278
Likes: 539
From: Kelowna BC
Makes sense...
With this: "10-PCM P0300 H C - Engine Misfire Detected"
And this: "All 8 spark plugs were replaced 6 months ago." (no wires mentioned)
It makes sense that it was a wire(s). Old wires get brittle. Never mind the fact that if changing plugs, just pulling your wires might cause a break. Sorry I didn't see this part earlier, would have been my first guess with the 2 above put together.
With this: "10-PCM P0300 H C - Engine Misfire Detected"
And this: "All 8 spark plugs were replaced 6 months ago." (no wires mentioned)
It makes sense that it was a wire(s). Old wires get brittle. Never mind the fact that if changing plugs, just pulling your wires might cause a break. Sorry I didn't see this part earlier, would have been my first guess with the 2 above put together.
Le Mans Master
Joined: Sep 2013
Posts: 8,900
Likes: 1,074
From: Wisconsin
Makes sense...
With this: "10-PCM P0300 H C - Engine Misfire Detected"
And this: "All 8 spark plugs were replaced 6 months ago." (no wires mentioned)
It makes sense that it was a wire(s). Old wires get brittle. Never mind the fact that if changing plugs, just pulling your wires might cause a break. Sorry I didn't see this part earlier, would have been my first guess with the 2 above put together.
With this: "10-PCM P0300 H C - Engine Misfire Detected"
And this: "All 8 spark plugs were replaced 6 months ago." (no wires mentioned)
It makes sense that it was a wire(s). Old wires get brittle. Never mind the fact that if changing plugs, just pulling your wires might cause a break. Sorry I didn't see this part earlier, would have been my first guess with the 2 above put together.
Le Mans Master
Joined: Jan 2004
Posts: 9,488
Likes: 1,743
From: Knoxville Tn
Le Mans Master
Joined: Sep 2013
Posts: 8,900
Likes: 1,074
From: Wisconsin
.....or the dealer just piling on the parts and labor. I could see 1 coil going bad, but 3 at the same time?
