Looking for ECM Information
Intermediate
Joined: Apr 2026
Posts: 26
Likes: 8
I also believe in the measure twice cut once philosophy so plan on visiting them and finding out what device was actually used to pull that code and have them use it to show me. Although the fact that it just cranks and has fuel pressure does point to an ignition problem.
Last edited by Gary TCB; Jun 4, 2026 at 11:53 PM. Reason: clarification
Thread Starter
Drifting
Joined: Nov 2018
Posts: 1,806
Likes: 580
From: Mays Landing, NJ
The fact that the car went from running great with easy starting to only cranking with no firing at all shows there is zero spark at the plugs. Based on that either the the Opti isn't sending spark to the plugs or the ECM/PCM isn't sending signal for spark. You mention a "new fashioned test", can you elaborate on that test for opti?
Intermediate
Joined: Apr 2026
Posts: 26
Likes: 8
Hi Corvette Rules
Please forgive the delay in responding - I am on a very different time zone in Australia. When I do a google search for "optispark test for spark" AI google lists instructions and reults deciphering for a two step "on car" procedure.
Step 1. Check for spark at the Ignition Coil
Step 2. Test the Optispark Optical Signal
Other forum members with Optispark experience (which I do not have) may chime in more information about the process.
Gary
Please forgive the delay in responding - I am on a very different time zone in Australia. When I do a google search for "optispark test for spark" AI google lists instructions and reults deciphering for a two step "on car" procedure.
Step 1. Check for spark at the Ignition Coil
Step 2. Test the Optispark Optical Signal
Other forum members with Optispark experience (which I do not have) may chime in more information about the process.
Gary
Thread Starter
Drifting
Joined: Nov 2018
Posts: 1,806
Likes: 580
From: Mays Landing, NJ
Guys and gals just thought of something about my issue. While the fuel pressure is good at prime and while cranking could there be an issue that the injectors aren't firing? I'll bring that up with the mechanic on Monday, but just want the forum members thoughts and let me know if I'm just grasping at straws.
Another question I'd like thoughts on is if I indeed I have to replace the Opti should I have the water pump replaced even though it's working fine with no signs of seepage? Looking at the state of replacement parts today is there an actual replacement water pump better then the crappy China parts?
Another question I'd like thoughts on is if I indeed I have to replace the Opti should I have the water pump replaced even though it's working fine with no signs of seepage? Looking at the state of replacement parts today is there an actual replacement water pump better then the crappy China parts?
Thread Starter
Drifting
Joined: Nov 2018
Posts: 1,806
Likes: 580
From: Mays Landing, NJ
UPDATE
Made final decisions with mechanic with my 95. Opti has power and ground but no outgoing voltages based on flow chart tests done. At this point have gave them go ahead to replace Opti and water pump since they'll be there anyway. Found nothing in history to indicate the water pump was ever replaced. We agreed that they'll obtain parts with the best warranty and reasonable reviews. The garage has treated me right over the years and I trust them. Hopefully by end of next week it will be back on the rode again..
With the history of crappy Chinese parts everything seems to be a crapshoot today but I'll jump into deep side of the pool and hope not to drown.
Made final decisions with mechanic with my 95. Opti has power and ground but no outgoing voltages based on flow chart tests done. At this point have gave them go ahead to replace Opti and water pump since they'll be there anyway. Found nothing in history to indicate the water pump was ever replaced. We agreed that they'll obtain parts with the best warranty and reasonable reviews. The garage has treated me right over the years and I trust them. Hopefully by end of next week it will be back on the rode again..
With the history of crappy Chinese parts everything seems to be a crapshoot today but I'll jump into deep side of the pool and hope not to drown.
Burning Brakes
Joined: Aug 2008
Posts: 909
Likes: 229
From: Tampa, FL
UPDATE
Made final decisions with mechanic with my 95. Opti has power and ground but no outgoing voltages based on flow chart tests done. At this point have gave them go ahead to replace Opti and water pump since they'll be there anyway. Found nothing in history to indicate the water pump was ever replaced. We agreed that they'll obtain parts with the best warranty and reasonable reviews. The garage has treated me right over the years and I trust them. Hopefully by end of next week it will be back on the rode again..
With the history of crappy Chinese parts everything seems to be a crapshoot today but I'll jump into deep side of the pool and hope not to drown.
Made final decisions with mechanic with my 95. Opti has power and ground but no outgoing voltages based on flow chart tests done. At this point have gave them go ahead to replace Opti and water pump since they'll be there anyway. Found nothing in history to indicate the water pump was ever replaced. We agreed that they'll obtain parts with the best warranty and reasonable reviews. The garage has treated me right over the years and I trust them. Hopefully by end of next week it will be back on the rode again..
With the history of crappy Chinese parts everything seems to be a crapshoot today but I'll jump into deep side of the pool and hope not to drown.
FYI, @FAUEE on here relocated the ignition control module from the OptiSpark, if I'm not mistaken, which has resulted in better reliability (or at least improved cooling and moving it out of the way of possible water intrusion).
Race Director
Joined: Oct 2012
Posts: 17,398
Likes: 6,536
From: Melbourne, FL
FYI, @FAUEE on here relocated the ignition control module from the OptiSpark, if I'm not mistaken, which has resulted in better reliability (or at least improved cooling and moving it out of the way of possible water intrusion).
Optispark reliability is, in my opinion, really just a matter of keeping it, and more importantly it's wiring harness dry. The venting of later versions I'm sure helps some by pulling away moisture if any gets in, but not getting liquid inside of it isnino the best solution.
Or Torqhead if your year supports it.
Thread Starter
Drifting
Joined: Nov 2018
Posts: 1,806
Likes: 580
From: Mays Landing, NJ
I relocated the ICM, which is typically co-located with the coil. It's separate from the optispark, though it is somewhat in that pathway. The ICM in effect fires the coil, which passes the spark to the optispark's distributor section.
Optispark reliability is, in my opinion, really just a matter of keeping it, and more importantly it's wiring harness dry. The venting of later versions I'm sure helps some by pulling away moisture if any gets in, but not getting liquid inside of it isnino the best solution.
Or Torqhead if your year supports it.
Optispark reliability is, in my opinion, really just a matter of keeping it, and more importantly it's wiring harness dry. The venting of later versions I'm sure helps some by pulling away moisture if any gets in, but not getting liquid inside of it isnino the best solution.
Or Torqhead if your year supports it.
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