Optispark HELP PLEASE!!!
Thread Starter
5th Gear
Joined: Jun 2013
Posts: 5
Likes: 0
Optispark HELP PLEASE!!!
So I think I got Optispark issue's. A few years ago I bought a 69 Blazer(I realize its not a vette and yes we do own a 65 and a 01 vette) with the LT1 in it. At first it would run rough, hard start and the idle was all over the place. So I put in a new Optispark II and it ran great until 6 months ago. From what I can tell its a 1996 lt1. Then it started shift weird when I hit the passing gear. I thought it was my trans linkage(700r4) so I put in all new lokar set up. It help but didn't fix it. I parked it until now and its back to my first symptoms and it is farting/popping. I could hear a ticking noise at the optispark. So I pulled it apart and put in a new cap/rotor. I put it back together and it runs awesome but idle's at 1400rpm. I took it for a drive and could hear a vacuum leak. I turned it off found the leak and fixed it. NOW it won't start????? No spark???
I've checked all wire connection. I did the coil/wire/plugs when I did the opti 2 years ago. I be lucky if I've put 5000k on it since Ive had it. I changed the ignition regulator. I've tried restarting it the vacuum leak unhooked and made no difference. All fuse's are good.
Help Please. Thanks in advance. Cam
I've checked all wire connection. I did the coil/wire/plugs when I did the opti 2 years ago. I be lucky if I've put 5000k on it since Ive had it. I changed the ignition regulator. I've tried restarting it the vacuum leak unhooked and made no difference. All fuse's are good.
Help Please. Thanks in advance. Cam
Advanced
Joined: May 2011
Posts: 57
Likes: 0
From: Cleveland Ohio
Optispark
go on Youtube. Look for a video GM Buick put out on the Optispark.
You need to understand how the unit works first.
Do you store your car in the winter? that will affect the inside of the unit with moisture. I had installed a brand new OPti two years ago.
I only put 10,000 miles on it. I purchased it from Sumitt racing, they do not warrant their stuff. It went bad this spring. I live in Northeast Ohio. We had a Mother of a Winter. This time I purchased one with a lifetime warranty.
Again, Look up the GM video on Youtube.
You need to understand how the unit works first.
Do you store your car in the winter? that will affect the inside of the unit with moisture. I had installed a brand new OPti two years ago.
I only put 10,000 miles on it. I purchased it from Sumitt racing, they do not warrant their stuff. It went bad this spring. I live in Northeast Ohio. We had a Mother of a Winter. This time I purchased one with a lifetime warranty.
Again, Look up the GM video on Youtube.
Thread Starter
5th Gear
Joined: Jun 2013
Posts: 5
Likes: 0
go on Youtube. Look for a video GM Buick put out on the Optispark.
You need to understand how the unit works first.
Do you store your car in the winter? that will affect the inside of the unit with moisture. I had installed a brand new OPti two years ago.
I only put 10,000 miles on it. I purchased it from Sumitt racing, they do not warrant their stuff. It went bad this spring. I live in Northeast Ohio. We had a Mother of a Winter. This time I purchased one with a lifetime warranty.
Again, Look up the GM video on Youtube.
You need to understand how the unit works first.
Do you store your car in the winter? that will affect the inside of the unit with moisture. I had installed a brand new OPti two years ago.
I only put 10,000 miles on it. I purchased it from Sumitt racing, they do not warrant their stuff. It went bad this spring. I live in Northeast Ohio. We had a Mother of a Winter. This time I purchased one with a lifetime warranty.
Again, Look up the GM video on Youtube.
Melting Slicks
Joined: Jul 2005
Posts: 2,649
Likes: 863
There are a number of conditions that will cause a no sprak situation on LT1 / LT4 Cars. It could certainly be the Optispark, or the Coil Driver module, or the coil, or the PCM, or a few other things.
First question - do you have any error codes ??? The Optispark systems uses two signals - a high resolution signal, and a low resolution signal. If the PCM sees one - but not the other, an error code should be set.
My suggestions would be:
1) Check the pos side of the ignition coil to see if you have 12 Volts. Then, while having a friend crank the car, see if the voltage on the neg side of the coil varies from 0 Volts to 12 Volts and back. It should be doing that - if it isn't you're making progress.
2) To see if the opti is working correctly - you'll need to backprobe the connections while cranking - using a decent quality Digital Voltmeter - if you can find one that has a frequency function - that would be so much the better. On the pass side of the motor, under the plastic cover, you will find a four pin connector that is attached to the intake manifold with a single bolt - that connector goes to the optispark. The connections are as follows:
Pin "A" - Low Res Signal
Pin "B" - High Resolution Signal
Pin "C" - Ignition "Feed"
Pin "D" - Ground
Assuming that Pins "C" and "D" are reading the correct values with the ignition switch on, you want to verify that there is rapidly varying voltage at Pin "A" during cranking, and not quite so rapidly varying voltage at Pin "B" (this is where the frequency function on the meter would come in handy). If this is the case - the opti is almost certainly NOT the cause of the no start condition. If the outputs on Pin "A" or "B" are not correct and you're sure you are backprobing correctly - you get to go buy a new opti. (You can verify that the opti was bad by plugging a new opti into the wiring harness, pulling the coil wire off the ignition coil, and putting it near a good ground, turning on the Ignition, and spinning the opti by hand. You should see a nice series of sparks off the coil. Go back and do it with the old opti - and you won't see the sparks.
If the opti is working - your next thing to check is the coil driver module. It's basically a electronic "relay" that allows the PCM to control the ignition system. Since the PCM can't handle the current that the ignition uses, they use the coil driver as the intermediary that handles the current. Ignition coils are really simple things. They always see 12 Volts on the pos side. "Normally" the neg side of the coil is switched from ground to open. (In the 1970's the switching was done by points - now it's done electronically.) When the points are closed - current flows through the coil primary to ground - when the "points" open - the current flow stops and the magnetic field that was created collapses, thus creating the spark in the secondary side of the coil. On the LT1/LT4 Cars, the Coil Driver is always getting 12 Volts when the ignition system is on, and it allows the neg side of the coil to be grounded when the PCM tells it to. The PCM then "tells" the Coil Driver to switch off the current flow, and if everything is working correctly - that's what happens. You can verify that the coil driver is working properly - by checking the voltage on pins "B" and "D". Pin "B" is the connection from the PCM to the low power side of the Coil Driver - so it the opti and PCM are both working correctly - the voltage at this terminal will vary during cranking. If that is the case - the voltage on the high power side of the Coil Driver (Pin "D" should also vary during cranking.
However - we can test the Coil Driver by disconnecting the factory wire to Pin "B", and with a test lead hooked up to Pin "B" - rapidly cycle that lead to ground and back off, the Coil Driver will think it's being told to switch the Ignition coil current on and off, and if it's working correctly - will create sparks from the ignition coil. If it's not working correctly - the coil will just sit there with the same voltage on Pin "D" regardless of what's going on with the ground wire jumper (Note - if you do not disconnect the wire to pin "D" before doing this test - you are probably going to burn up the PCM...
First question - do you have any error codes ??? The Optispark systems uses two signals - a high resolution signal, and a low resolution signal. If the PCM sees one - but not the other, an error code should be set.
My suggestions would be:
1) Check the pos side of the ignition coil to see if you have 12 Volts. Then, while having a friend crank the car, see if the voltage on the neg side of the coil varies from 0 Volts to 12 Volts and back. It should be doing that - if it isn't you're making progress.
2) To see if the opti is working correctly - you'll need to backprobe the connections while cranking - using a decent quality Digital Voltmeter - if you can find one that has a frequency function - that would be so much the better. On the pass side of the motor, under the plastic cover, you will find a four pin connector that is attached to the intake manifold with a single bolt - that connector goes to the optispark. The connections are as follows:
Pin "A" - Low Res Signal
Pin "B" - High Resolution Signal
Pin "C" - Ignition "Feed"
Pin "D" - Ground
Assuming that Pins "C" and "D" are reading the correct values with the ignition switch on, you want to verify that there is rapidly varying voltage at Pin "A" during cranking, and not quite so rapidly varying voltage at Pin "B" (this is where the frequency function on the meter would come in handy). If this is the case - the opti is almost certainly NOT the cause of the no start condition. If the outputs on Pin "A" or "B" are not correct and you're sure you are backprobing correctly - you get to go buy a new opti. (You can verify that the opti was bad by plugging a new opti into the wiring harness, pulling the coil wire off the ignition coil, and putting it near a good ground, turning on the Ignition, and spinning the opti by hand. You should see a nice series of sparks off the coil. Go back and do it with the old opti - and you won't see the sparks.
If the opti is working - your next thing to check is the coil driver module. It's basically a electronic "relay" that allows the PCM to control the ignition system. Since the PCM can't handle the current that the ignition uses, they use the coil driver as the intermediary that handles the current. Ignition coils are really simple things. They always see 12 Volts on the pos side. "Normally" the neg side of the coil is switched from ground to open. (In the 1970's the switching was done by points - now it's done electronically.) When the points are closed - current flows through the coil primary to ground - when the "points" open - the current flow stops and the magnetic field that was created collapses, thus creating the spark in the secondary side of the coil. On the LT1/LT4 Cars, the Coil Driver is always getting 12 Volts when the ignition system is on, and it allows the neg side of the coil to be grounded when the PCM tells it to. The PCM then "tells" the Coil Driver to switch off the current flow, and if everything is working correctly - that's what happens. You can verify that the coil driver is working properly - by checking the voltage on pins "B" and "D". Pin "B" is the connection from the PCM to the low power side of the Coil Driver - so it the opti and PCM are both working correctly - the voltage at this terminal will vary during cranking. If that is the case - the voltage on the high power side of the Coil Driver (Pin "D" should also vary during cranking.
However - we can test the Coil Driver by disconnecting the factory wire to Pin "B", and with a test lead hooked up to Pin "B" - rapidly cycle that lead to ground and back off, the Coil Driver will think it's being told to switch the Ignition coil current on and off, and if it's working correctly - will create sparks from the ignition coil. If it's not working correctly - the coil will just sit there with the same voltage on Pin "D" regardless of what's going on with the ground wire jumper (Note - if you do not disconnect the wire to pin "D" before doing this test - you are probably going to burn up the PCM...
Thread Starter
5th Gear
Joined: Jun 2013
Posts: 5
Likes: 0
There are a number of conditions that will cause a no sprak situation on LT1 / LT4 Cars. It could certainly be the Optispark, or the Coil Driver module, or the coil, or the PCM, or a few other things.
First question - do you have any error codes ??? The Optispark systems uses two signals - a high resolution signal, and a low resolution signal. If the PCM sees one - but not the other, an error code should be set.
My suggestions would be:
1) Check the pos side of the ignition coil to see if you have 12 Volts. Then, while having a friend crank the car, see if the voltage on the neg side of the coil varies from 0 Volts to 12 Volts and back. It should be doing that - if it isn't you're making progress.
2) To see if the opti is working correctly - you'll need to backprobe the connections while cranking - using a decent quality Digital Voltmeter - if you can find one that has a frequency function - that would be so much the better. On the pass side of the motor, under the plastic cover, you will find a four pin connector that is attached to the intake manifold with a single bolt - that connector goes to the optispark. The connections are as follows:
Pin "A" - Low Res Signal
Pin "B" - High Resolution Signal
Pin "C" - Ignition "Feed"
Pin "D" - Ground
Assuming that Pins "C" and "D" are reading the correct values with the ignition switch on, you want to verify that there is rapidly varying voltage at Pin "A" during cranking, and not quite so rapidly varying voltage at Pin "B" (this is where the frequency function on the meter would come in handy). If this is the case - the opti is almost certainly NOT the cause of the no start condition. If the outputs on Pin "A" or "B" are not correct and you're sure you are backprobing correctly - you get to go buy a new opti. (You can verify that the opti was bad by plugging a new opti into the wiring harness, pulling the coil wire off the ignition coil, and putting it near a good ground, turning on the Ignition, and spinning the opti by hand. You should see a nice series of sparks off the coil. Go back and do it with the old opti - and you won't see the sparks.
If the opti is working - your next thing to check is the coil driver module. It's basically a electronic "relay" that allows the PCM to control the ignition system. Since the PCM can't handle the current that the ignition uses, they use the coil driver as the intermediary that handles the current. Ignition coils are really simple things. They always see 12 Volts on the pos side. "Normally" the neg side of the coil is switched from ground to open. (In the 1970's the switching was done by points - now it's done electronically.) When the points are closed - current flows through the coil primary to ground - when the "points" open - the current flow stops and the magnetic field that was created collapses, thus creating the spark in the secondary side of the coil. On the LT1/LT4 Cars, the Coil Driver is always getting 12 Volts when the ignition system is on, and it allows the neg side of the coil to be grounded when the PCM tells it to. The PCM then "tells" the Coil Driver to switch off the current flow, and if everything is working correctly - that's what happens. You can verify that the coil driver is working properly - by checking the voltage on pins "B" and "D". Pin "B" is the connection from the PCM to the low power side of the Coil Driver - so it the opti and PCM are both working correctly - the voltage at this terminal will vary during cranking. If that is the case - the voltage on the high power side of the Coil Driver (Pin "D" should also vary during cranking.
However - we can test the Coil Driver by disconnecting the factory wire to Pin "B", and with a test lead hooked up to Pin "B" - rapidly cycle that lead to ground and back off, the Coil Driver will think it's being told to switch the Ignition coil current on and off, and if it's working correctly - will create sparks from the ignition coil. If it's not working correctly - the coil will just sit there with the same voltage on Pin "D" regardless of what's going on with the ground wire jumper (Note - if you do not disconnect the wire to pin "D" before doing this test - you are probably going to burn up the PCM...
First question - do you have any error codes ??? The Optispark systems uses two signals - a high resolution signal, and a low resolution signal. If the PCM sees one - but not the other, an error code should be set.
My suggestions would be:
1) Check the pos side of the ignition coil to see if you have 12 Volts. Then, while having a friend crank the car, see if the voltage on the neg side of the coil varies from 0 Volts to 12 Volts and back. It should be doing that - if it isn't you're making progress.
2) To see if the opti is working correctly - you'll need to backprobe the connections while cranking - using a decent quality Digital Voltmeter - if you can find one that has a frequency function - that would be so much the better. On the pass side of the motor, under the plastic cover, you will find a four pin connector that is attached to the intake manifold with a single bolt - that connector goes to the optispark. The connections are as follows:
Pin "A" - Low Res Signal
Pin "B" - High Resolution Signal
Pin "C" - Ignition "Feed"
Pin "D" - Ground
Assuming that Pins "C" and "D" are reading the correct values with the ignition switch on, you want to verify that there is rapidly varying voltage at Pin "A" during cranking, and not quite so rapidly varying voltage at Pin "B" (this is where the frequency function on the meter would come in handy). If this is the case - the opti is almost certainly NOT the cause of the no start condition. If the outputs on Pin "A" or "B" are not correct and you're sure you are backprobing correctly - you get to go buy a new opti. (You can verify that the opti was bad by plugging a new opti into the wiring harness, pulling the coil wire off the ignition coil, and putting it near a good ground, turning on the Ignition, and spinning the opti by hand. You should see a nice series of sparks off the coil. Go back and do it with the old opti - and you won't see the sparks.
If the opti is working - your next thing to check is the coil driver module. It's basically a electronic "relay" that allows the PCM to control the ignition system. Since the PCM can't handle the current that the ignition uses, they use the coil driver as the intermediary that handles the current. Ignition coils are really simple things. They always see 12 Volts on the pos side. "Normally" the neg side of the coil is switched from ground to open. (In the 1970's the switching was done by points - now it's done electronically.) When the points are closed - current flows through the coil primary to ground - when the "points" open - the current flow stops and the magnetic field that was created collapses, thus creating the spark in the secondary side of the coil. On the LT1/LT4 Cars, the Coil Driver is always getting 12 Volts when the ignition system is on, and it allows the neg side of the coil to be grounded when the PCM tells it to. The PCM then "tells" the Coil Driver to switch off the current flow, and if everything is working correctly - that's what happens. You can verify that the coil driver is working properly - by checking the voltage on pins "B" and "D". Pin "B" is the connection from the PCM to the low power side of the Coil Driver - so it the opti and PCM are both working correctly - the voltage at this terminal will vary during cranking. If that is the case - the voltage on the high power side of the Coil Driver (Pin "D" should also vary during cranking.
However - we can test the Coil Driver by disconnecting the factory wire to Pin "B", and with a test lead hooked up to Pin "B" - rapidly cycle that lead to ground and back off, the Coil Driver will think it's being told to switch the Ignition coil current on and off, and if it's working correctly - will create sparks from the ignition coil. If it's not working correctly - the coil will just sit there with the same voltage on Pin "D" regardless of what's going on with the ground wire jumper (Note - if you do not disconnect the wire to pin "D" before doing this test - you are probably going to burn up the PCM...
I multimetered the opti harness. both high and low resolution came in around 11.5. Ignition feed lights up my light and the ground is good.
At the ICM. A&D were both around 5volts. but on "B", from what I seen on the test video. Cranking it over barely made 0.2 and its suppose to be 1-4. According to the diagram I have, its the white wire "Ignition Control" so could this be the PCM?
