Sorry.
electronic spark control
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,123
Likes: 1
From: Rockland County NY
electronic spark control
A quick question for your combined knowledge...
My 91 L98 threw a code 43. I replaced the knock sensor but the car still stumbles at take off. On an earlier post, someone said it was located on the passenger side firewall. I called the GM dealer and they said it was located in the distributor. Anybody want to take a guess at the location of this thing? A picture would help too because I haven't been able to spot this thing. Thanks...
Mike
My 91 L98 threw a code 43. I replaced the knock sensor but the car still stumbles at take off. On an earlier post, someone said it was located on the passenger side firewall. I called the GM dealer and they said it was located in the distributor. Anybody want to take a guess at the location of this thing? A picture would help too because I haven't been able to spot this thing. Thanks...
Mike
Drifting
Joined: Dec 2007
Posts: 1,647
Likes: 4
From: Argillite KY
http://forums.corvetteforum.com/c4-t...sc-module.html
Post #8 has a pic of it on the passenger side near the gills, just below the HVAC motor.
Post #8 has a pic of it on the passenger side near the gills, just below the HVAC motor.
Safety Car
Joined: Oct 2008
Posts: 4,689
Likes: 4
From: Yucaipa CA
A quick question for your combined knowledge...
My 91 L98 threw a code 43. I replaced the knock sensor but the car still stumbles at take off. On an earlier post, someone said it was located on the passenger side firewall. I called the GM dealer and they said it was located in the distributor. Anybody want to take a guess at the location of this thing? A picture would help too because I haven't been able to spot this thing. Thanks...
Mike
My 91 L98 threw a code 43. I replaced the knock sensor but the car still stumbles at take off. On an earlier post, someone said it was located on the passenger side firewall. I called the GM dealer and they said it was located in the distributor. Anybody want to take a guess at the location of this thing? A picture would help too because I haven't been able to spot this thing. Thanks...
Mike
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,123
Likes: 1
From: Rockland County NY
Safety Car
Joined: Oct 2008
Posts: 4,689
Likes: 4
From: Yucaipa CA
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,123
Likes: 1
From: Rockland County NY
Safety Car
Joined: Oct 2008
Posts: 4,689
Likes: 4
From: Yucaipa CA
you are positive you used a 90-91 specific knock sensor right? I think a bad magnetic pickup assembly in the distributor will also cause 43 and cause stumbles and missfires. I had one go bad many years ago and it felt like at times car was running on 6 cylinders, bad fuel odor.
Did you clear codes after knock sensor was replaced?
Did you clear codes after knock sensor was replaced?
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Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,123
Likes: 1
From: Rockland County NY
you are positive you used a 90-91 specific knock sensor right? I think a bad magnetic pickup assembly in the distributor will also cause 43 and cause stumbles and missfires. I had one go bad many years ago and it felt like at times car was running on 6 cylinders, bad fuel odor.
Did you clear codes after knock sensor was replaced?
Did you clear codes after knock sensor was replaced?
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,123
Likes: 1
From: Rockland County NY
OK, found an ECM cheap so I grabbed it and am going to install it tonight. For what I paid for it, i figured what the hell. I just need to pull the chip out of mine and put it in this one. My questions are as follows.... 1. Do i need to disconnect the battery before hand?
2. Is there a learning process involved once it's all back
together?
2. Is there a learning process involved once it's all back
together?
Instructor
Joined: May 2001
Posts: 186
Likes: 0
From: Midwest
OK, found an ECM cheap so I grabbed it and am going to install it tonight. For what I paid for it, i figured what the hell. I just need to pull the chip out of mine and put it in this one. My questions are as follows.... 1. Do i need to disconnect the battery before hand?
2. Is there a learning process involved once it's all back
together?
2. Is there a learning process involved once it's all back
together?
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,123
Likes: 1
From: Rockland County NY
I installed the ECM last night. Took the car out today and the same problem is happening 
. Actually, it might be a little worse. "Service Engine Soon" light came on and stayed on. I shut it off, restarted it and light went out. Then I did the paper clip trick but no code was stored. How can that be?
So, originally the car threw a code 43. I replaced the knock sensor and the ECM (which houses the Electronic Spark Control). No more code 43, in fact, no codes at all anymore, but car is getting worse. WTF???
. Actually, it might be a little worse. "Service Engine Soon" light came on and stayed on. I shut it off, restarted it and light went out. Then I did the paper clip trick but no code was stored. How can that be?So, originally the car threw a code 43. I replaced the knock sensor and the ECM (which houses the Electronic Spark Control). No more code 43, in fact, no codes at all anymore, but car is getting worse. WTF???
Safety Car
Joined: Oct 2008
Posts: 4,689
Likes: 4
From: Yucaipa CA
I installed the ECM last night. Took the car out today and the same problem is happening . Actually, it might be a little worse. "Service Engine Soon" light came on and stayed on. I shut it off, restarted it and light went out. Then I did the paper clip trick but no code was stored. How can that be?
So, originally the car threw a code 43. I replaced the knock sensor and the ECM (which houses the Electronic Spark Control). No more code 43, in fact, no codes at all anymore, but car is getting worse. WTF???
. Actually, it might be a little worse. "Service Engine Soon" light came on and stayed on. I shut it off, restarted it and light went out. Then I did the paper clip trick but no code was stored. How can that be?So, originally the car threw a code 43. I replaced the knock sensor and the ECM (which houses the Electronic Spark Control). No more code 43, in fact, no codes at all anymore, but car is getting worse. WTF???
injectors
fuel pressure
cats
fuel filter
weak coil
run a vacuum test and fuel pressure test.
Thread Starter
Burning Brakes
Joined: Aug 2006
Posts: 1,123
Likes: 1
From: Rockland County NY
thanks Jeff, I was actually fiddling with the injector wires just to see if any were loose and the problem amplified. Maybe it is an injector problem. I'll borrow a volt meter and test them next. If they check out, I'll move to a fuel pressure test.
Safety Car
Joined: Oct 2008
Posts: 4,689
Likes: 4
From: Yucaipa CA
My best friends 90 once started running like a dog and had a hard time pulling above like 3500rpm and it was dead multec injectors. After replacing them ran good again but was still low on power and he had all cats replaced and that brough it back to good health. No codes ever were present on it.
