Check engine light op question......
Thread Starter
Pro
Joined: Mar 1999
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From: Cleveland Ohio
Check engine light op question......
Hi; I know my 91 (L98) has the OBDl system and I'm going to jump A&B and count the times flashed to hopefully get a code for direction but I'm a little confused and need some info.
Yesterday while on a longer drive since repairs (intake gaskets, flush, oil & lube, exhaust Y-pipe replaced with NO cats & center cat replaced-all cats were plugged) I finally noticed (top down-sun glare) that the check engine light had come on. I continued on, as gauges were all good, arrived and parked for 5 hours. When I fired it back up their was no light on and it continued that way for about a 1/2 hour of again freeway driving and then reappeared. When I stopped again I shut down and immediately refired and the light again was off. On the way home it popped on again after 15 minutes or so.
I believe on OBDll that once the light comes on it stays on and immediately appears after that when you refire. Is that also true on OBDl and is something strange happening? I sure hope it's a leaky gas cap!
Thanks, Frank
PS: Will my OBDll reader work on the OBDl system?
Yesterday while on a longer drive since repairs (intake gaskets, flush, oil & lube, exhaust Y-pipe replaced with NO cats & center cat replaced-all cats were plugged) I finally noticed (top down-sun glare) that the check engine light had come on. I continued on, as gauges were all good, arrived and parked for 5 hours. When I fired it back up their was no light on and it continued that way for about a 1/2 hour of again freeway driving and then reappeared. When I stopped again I shut down and immediately refired and the light again was off. On the way home it popped on again after 15 minutes or so.
I believe on OBDll that once the light comes on it stays on and immediately appears after that when you refire. Is that also true on OBDl and is something strange happening? I sure hope it's a leaky gas cap!
Thanks, Frank
PS: Will my OBDll reader work on the OBDl system?
Last edited by Frank C; Jul 16, 2010 at 10:09 AM. Reason: adding
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Hi; I know my 91 (L98) has the OBDl system and I'm going to jump A&B and count the times flashed to hopefully get a code for direction but I'm a little confused and need some info.
Yesterday while on a longer drive since repairs (intake gaskets, flush, oil & lube, exhaust Y-pipe replaced with NO cats & center cat replaced-all cats were plugged) I finally noticed (top down-sun glare) that the check engine light had come on. I continued on, as gauges were all good, arrived and parked for 5 hours. When I fired it back up their was no light on and it continued that way for about a 1/2 hour of again freeway driving and then reappeared. When I stopped again I shut down and immediately refired and the light again was off. On the way home it popped on again after 15 minutes or so.
I believe on OBDll that once the light comes on it stays on and immediately appears after that when you refire. Is that also true on OBDl and is something strange happening? I sure hope it's a leaky gas cap!
Thanks, Frank
PS: Will my OBDll reader work on the OBDl system?
Yesterday while on a longer drive since repairs (intake gaskets, flush, oil & lube, exhaust Y-pipe replaced with NO cats & center cat replaced-all cats were plugged) I finally noticed (top down-sun glare) that the check engine light had come on. I continued on, as gauges were all good, arrived and parked for 5 hours. When I fired it back up their was no light on and it continued that way for about a 1/2 hour of again freeway driving and then reappeared. When I stopped again I shut down and immediately refired and the light again was off. On the way home it popped on again after 15 minutes or so.
I believe on OBDll that once the light comes on it stays on and immediately appears after that when you refire. Is that also true on OBDl and is something strange happening? I sure hope it's a leaky gas cap!
Thanks, Frank
PS: Will my OBDll reader work on the OBDl system?
Get the codes and post up the codes.
That sounds like a code 32 to me. EGR problem. On long cruise's it will show up and disapear later after driving.
2 kinds of codes. Soft code is what you are seeing. Hard codes stay lit.
Good luck
Corvette Mike
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Sounds like you're a bit nervous about pulling your trouble codes for the first time. It's ok.
Stop by AutoZone and pick up one of those free OBD 1 code keys.
They're pre-cut to fit into the data terminal diagnostic port and minimize the possibility of patching into the wrong row of connectors.
Stop by AutoZone and pick up one of those free OBD 1 code keys.
They're pre-cut to fit into the data terminal diagnostic port and minimize the possibility of patching into the wrong row of connectors.
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Sounds like you're a bit nervous about pulling your trouble codes for the first time. It's ok.
Stop by AutoZone and pick up one of those free OBD 1 code keys.
They're pre-cut to fit into the data terminal diagnostic port and minimize the possibility of patching into the wrong row of connectors.
Stop by AutoZone and pick up one of those free OBD 1 code keys.
They're pre-cut to fit into the data terminal diagnostic port and minimize the possibility of patching into the wrong row of connectors.
Thread Starter
Pro
Joined: Mar 1999
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From: Cleveland Ohio
Thanks Guys; No, not nervous just unsure about light duration. It has been a long time since I jumped the A&B with a paper clip and counted the flashes. Didn't know about that AutoZone benny. I'll check into it.
Meanwhile, will my OBD 2 reader work on a OBD l system to read the codes.
I did check the EGR at gasket time (2 weeks) and it was working but ya never know.
Nice to know that the reason for the lights disappearance is a soft code as opposed to a hard one. Didn't know that there were two kinds... Thanks again, Frank
Meanwhile, will my OBD 2 reader work on a OBD l system to read the codes.
I did check the EGR at gasket time (2 weeks) and it was working but ya never know.
Nice to know that the reason for the lights disappearance is a soft code as opposed to a hard one. Didn't know that there were two kinds... Thanks again, Frank
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Use a dental mirror under egr valve and see if you can see any movement. Good luck.
Your car will run fine like this.
Mike
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Thread Starter
Pro
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From: Cleveland Ohio
Good news, I took a peek and saw the vacuum line just laying there unattached. I reattached it and if the light stays off I'll disconnect the battery to clear the codes, and reset all the radio stations, again. Turned out even better then a gas cap.
Thanks to all and especially Corvette Mike 2004, Frank
Now back to that big block, overheating at idle, 32..............
Thanks to all and especially Corvette Mike 2004, Frank
Now back to that big block, overheating at idle, 32..............
Thread Starter
Pro
Joined: Mar 1999
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From: Cleveland Ohio
What BB
My 32 has a 30 over (402) 68/396. Lumpy cam, small port heads, Performer under a 750 Edelbrock. 700R4 with a 9"/3.50 posi and Wilwoods at the corners. At 68 years and ageing the steelpacks are getting a little loud on long trips. When caught in traffic she has a tendency to run a little hot. 220 And climbing has been the latest trick. It's a Griffin with a 2800 rpm puller and no shroud but that shouldn't be a problem or at least it hadn't been till I was at a Columbus GoodGuys and over heated in line, on the freeway. Dumb on my part but...............240's not to high is it? I've got a vacuum Unilite to install for the now mechanical Unilite and I should advance to at least 12', 10.5 now and that all would help cool it at idle. Have to pull the engine to get the 1/2" longer Dist in or cut the firewall so I've been putting it off for a while now. Summer lazy I guess!
I have an couple of engine pics but don't do pics well here.............Frank
I have an couple of engine pics but don't do pics well here.............Frank
