optispark and timing
Thread Starter
Melting Slicks
Joined: Oct 2004
Posts: 2,283
Likes: 0
From: Leeds Alabama
optispark and timing
replaced a bad opti on a 93 . it wouldnt run before . . . now cranks and runs . Timing seems way off like spark plug wires are crossed . . . triple checked they are not. Hard start and miss . I know the opti drive gear is slotted as well as the gear inside the timing cover. Both aligned fine. I cant imagine getting it 180 out , and if by some magical coincidence I did, it wouldnt run at all .. . . right? Any thoughts?
Thread Starter
Melting Slicks
Joined: Oct 2004
Posts: 2,283
Likes: 0
From: Leeds Alabama
I did replace with new gm . I just pulled the water pump again and re checked new gm wires ...they were correct. Now I sometimes do and do not get a code 41 . I have done the service manual diagnostic tree.
car runs ok then sputters ping and shuts off. I have replaced coil and module.
I doubt the optispark is on wrong because it runs fine for a little bit then acts up.
car runs ok then sputters ping and shuts off. I have replaced coil and module.
I doubt the optispark is on wrong because it runs fine for a little bit then acts up.
Race Director
Joined: Jan 2002
Posts: 12,261
Likes: 85
From: O'Fallon Missouri
It would be really hard to get an early opti misaligned. If so, you would have to force the opti on. But, it sounds like either crossed plug wires or a misaligned opti.
Did you check to make sure all sensors were plugged back in after the install?
Did you check to make sure all sensors were plugged back in after the install?
Le Mans Master
Joined: Jan 2006
Posts: 5,620
Likes: 206
From: Orlando FL
I would do a fuel pressure check just to make sure the pressure is OK. Low pressure would cause all kinds of running problems. Take a break from the ignition stuff and do a pressure check and cover another base.
Others have aligned the opti wrong and said it couldn’t be done. But from what I remember, it usually does not start. The opti should go on real easy and hit the cover with a tink. The bolts don’t pull it in, just hold it in place. But I think you know that.
Others have aligned the opti wrong and said it couldn’t be done. But from what I remember, it usually does not start. The opti should go on real easy and hit the cover with a tink. The bolts don’t pull it in, just hold it in place. But I think you know that.
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Thread Starter
Melting Slicks
Joined: Oct 2004
Posts: 2,283
Likes: 0
From: Leeds Alabama
plenty of codes before opti - now getting ecm41. Looks like the ecm is bad.
Here is what I did....................
pulled plug on coil driver. Tested voltage with ign on .... .053
removed connector "a" from ecm ...voltage went to 10.xxx
Looks like ecm time.
Here is what I did....................
pulled plug on coil driver. Tested voltage with ign on .... .053
removed connector "a" from ecm ...voltage went to 10.xxx
Looks like ecm time.
Last edited by corvette1989bham; Jan 15, 2007 at 11:20 PM.
Safety Car
Joined: Apr 2003
Posts: 3,793
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From: VA
Do a search on camaroz28.com you will find lots of examples.
Pro
Joined: Aug 2004
Posts: 538
Likes: 1
From: ATLANTA GA
Master Mechanic
Guys I might be boasting a little here but my C4 had been down since October 05 and had been seen by many mechanics in the Atlanta area.
Bill Heard CHEVROLET HAD MY CAR FOR 9-WEEKS called me and said come get it we cant fix it. I finally got in touch with Chris a member of this forum corvette1989bham. I shipped the car to him just outside birminham and he fixed my car within a couple weeks. The dealership had messed up the wiring harness on the car so some pretty extensive investigation and troubleshooting had to be done to fix it. I just want to say if you have something you or noone has been able to handle SEND IT TO CHRIS he was very reasonable and had the means and the place to work on these cars. Thanks again Chris for ending my nightmare.
Bill Heard CHEVROLET HAD MY CAR FOR 9-WEEKS called me and said come get it we cant fix it. I finally got in touch with Chris a member of this forum corvette1989bham. I shipped the car to him just outside birminham and he fixed my car within a couple weeks. The dealership had messed up the wiring harness on the car so some pretty extensive investigation and troubleshooting had to be done to fix it. I just want to say if you have something you or noone has been able to handle SEND IT TO CHRIS he was very reasonable and had the means and the place to work on these cars. Thanks again Chris for ending my nightmare.
Intermediate
Joined: Jun 2006
Posts: 49
Likes: 0
Fixed
Guys I might be boasting a little here but my C4 had been down since October 05 and had been seen by many mechanics in the Atlanta area.
Bill Heard CHEVROLET HAD MY CAR FOR 9-WEEKS called me and said come get it we cant fix it. I finally got in touch with Chris a member of this forum corvette1989bham. I shipped the car to him just outside birminham and he fixed my car within a couple weeks. The dealership had messed up the wiring harness on the car so some pretty extensive investigation and troubleshooting had to be done to fix it. I just want to say if you have something you or noone has been able to handle SEND IT TO CHRIS he was very reasonable and had the means and the place to work on these cars. Thanks again Chris for ending my nightmare.
Bill Heard CHEVROLET HAD MY CAR FOR 9-WEEKS called me and said come get it we cant fix it. I finally got in touch with Chris a member of this forum corvette1989bham. I shipped the car to him just outside birminham and he fixed my car within a couple weeks. The dealership had messed up the wiring harness on the car so some pretty extensive investigation and troubleshooting had to be done to fix it. I just want to say if you have something you or noone has been able to handle SEND IT TO CHRIS he was very reasonable and had the means and the place to work on these cars. Thanks again Chris for ending my nightmare.
Team Owner
Joined: Mar 2001
Posts: 30,845
Likes: 293
From: Boston, Dallas, Detroit, SoCal, back to Boston MA
You CAN install an opti the wrong way. I've done it 
Also check the leads going into the opti. Sometimes the computer hookup corodes.
Next up is the ignition coil and module.
Make sure the wires aren't crossed either.
Also check the leads going into the opti. Sometimes the computer hookup corodes.
Next up is the ignition coil and module.
Make sure the wires aren't crossed either.
Le Mans Master
Joined: Mar 2001
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From: Life is just one big track event. Everything before and after is prep and warm-up and cool-down laps
Cruise-In III Veteran
Cruise-In IV Veteran
St. Jude Donor '12
I found that even pushing it with my hand almost got it on in the wrong position!
Thread Starter
Melting Slicks
Joined: Oct 2004
Posts: 2,283
Likes: 0
From: Leeds Alabama
There were many problems, most of them from the technicians not knowing the proper way to test the different components and hacking up thw wiring harness to test circuits. The main problem was the opti and coil bad, next the serial data circuit was hacked up throwing all kinds of false codes. I completely cut out the serial data circuit and rebuilt my own. Wiring connectors for ignition module, and idle air control motor ruined from backprobing...replace all connectors. Replaced ECM due to jumper wire being installed backwards. In all, it took about 40 plus labor hours to fix a 7 labor hour job had it been diagnosed correctly the first time. Also, re-installed the original CCM to replace the used ccm that was installed by dealer when they thought it was bad too (it wasnt)
