2nd Opti-Spark in 2 Years?
Thread Starter
7th Gear
Joined: Jul 2006
Posts: 7
Likes: 0
2nd Opti-Spark in 2 Years?
I have a 92 that had the opti-spark and water pump done just over 2 years ago. Recently, I had a weird experience when backing the car out of the garage. Speed/Odometer and outside temp guage turned to metric. In addition the fan started running. After disconnecting and reconnecting, the battery the guages went back to English representation. The fan, however, stays on even on a cold start. I took the car in to my corvertte shop and they are telling me that it the opti and water pump again. They are basing this on the code that its showing. The "Service Engine Soon" is on and the "Service Ride Control" was on but now is not coming on.
Basically, I don't believe that this is the problem. The car drives fine except for the fan runnning and I see no evidence of a leaking water pump. I have put on only about 2K in miles since the last Opti and it never gets driven in the rain.
Question: Does anyone know of error codes that are incorrect? or any ideas on what else it could be? I don't know what code it showed but I'll give my vette shop the benefit of the doubt that it points to the distributor but I think its wrong. Thank you all in advance for your help.
Basically, I don't believe that this is the problem. The car drives fine except for the fan runnning and I see no evidence of a leaking water pump. I have put on only about 2K in miles since the last Opti and it never gets driven in the rain.
Question: Does anyone know of error codes that are incorrect? or any ideas on what else it could be? I don't know what code it showed but I'll give my vette shop the benefit of the doubt that it points to the distributor but I think its wrong. Thank you all in advance for your help.
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
First ask them what codes they had and pull them yourself and post them here. The opti codes will not make a fan come on but others do. I tend to agree with you the opti is not the issue. I have seen some corvette shops rip people off and they could not find ther own azz with 2 hands. The previous owner of my car had a bunch of expensive stuff done that did not fix his problem. It was a leaky neck on the surge tank it took me one day to find and fix. He paid over $700(new radiator,WP) to them I spent $45. 'nuff said on that.
Thread Starter
7th Gear
Joined: Jul 2006
Posts: 7
Likes: 0
Code is 36
Thanks for your interest. The code is 36. An auto electrical guy gave it a look and pulled the code and due to the other metric stuff thinks its not the opti-spark. His advice is to drive it a lot and monitor the guages, indicators , etc.. He doesn't feel that I am doing any damage by the fan running and driving it.
Le Mans Master
Joined: Dec 2004
Posts: 5,789
Likes: 8
From: Myrtle Beach SC
St. Jude Donor '05-'06
So you have only 1 code? A code 36 is the high res portion and the car will run with it. If you get the 16 it is toast(opti). That being said does not automatically make it the opti could be wiring not making good contact. Your fan since you have no other codes may be a stuck relay. You need to get a FSM for your car to properly troubleshoot your issues. Mabey someone will chime in on the relay location. I believ it is next to the radiator in front not sure though. If it is stuck you might be able to bang it and release it just to be sure( but then again it might not come back on).
Cruising
Joined: Mar 2011
Posts: 14
Likes: 1
From: Lewis Center OH
Ever solve problem...?
RJMarr...I know you posted this 2+ years ago, however I was wondering what the solution to you opti/code 36 problem was? My '93 Vette just started showing the exact same symptoms as what you described:
opti changed 3K miles (1 year ago) by professional vette mechanic.
Car was running perfect, no issues...then the Service Engine Soon light came on. I pulled code and it was code 36. The fans (both) come on at start up. Other wise car seems to be running well, no performance issues. I have been driving it some, approx 100 miles since SES came on. I spoke with mechanic who installed opti last year and he said emphatically it was not a bad opti because if it was it wouldn't start or would run very rough. There are only 19.5K miles on the car.
I am working through the FSM. I am getting 4.7V from the ECM to the opti. Previous owner had installed Hypertech chip, I am going to remove that and re-activate original PROM. I will hook up oscilloscope to monitor low/high opto outputs to make sure they are correct levels. Please share what your problem turned out to be....thx
opti changed 3K miles (1 year ago) by professional vette mechanic.
Car was running perfect, no issues...then the Service Engine Soon light came on. I pulled code and it was code 36. The fans (both) come on at start up. Other wise car seems to be running well, no performance issues. I have been driving it some, approx 100 miles since SES came on. I spoke with mechanic who installed opti last year and he said emphatically it was not a bad opti because if it was it wouldn't start or would run very rough. There are only 19.5K miles on the car.
I am working through the FSM. I am getting 4.7V from the ECM to the opti. Previous owner had installed Hypertech chip, I am going to remove that and re-activate original PROM. I will hook up oscilloscope to monitor low/high opto outputs to make sure they are correct levels. Please share what your problem turned out to be....thx
