No spark New Opti
#1
No spark New Opti
I have an unusual no start with my '94 Transam.
It has only 80K, is all stock and in good tune.
Car ran great till I hit exactly 90 MPH then it died but imediatly restarted. This happened 3 times at the same speed. During this time I could downshift and run it up to near redline without a miss.
Since the last trip to 90 it will not fire and has no spark.
I checked the coil with an ohm meter and it shows fine across high and low sides. I then replaced the opti, but still no spark.
I have proper voltage to the coil. Other PCM functions seem fine including injector pulse.
What else could I try???
Is seems peculiar to me that it only happened at a particular speed.
I am really tired of seeing my toy on jackstands.
Any help would be appriciated.
Wes
It has only 80K, is all stock and in good tune.
Car ran great till I hit exactly 90 MPH then it died but imediatly restarted. This happened 3 times at the same speed. During this time I could downshift and run it up to near redline without a miss.
Since the last trip to 90 it will not fire and has no spark.
I checked the coil with an ohm meter and it shows fine across high and low sides. I then replaced the opti, but still no spark.
I have proper voltage to the coil. Other PCM functions seem fine including injector pulse.
What else could I try???
Is seems peculiar to me that it only happened at a particular speed.
I am really tired of seeing my toy on jackstands.
Any help would be appriciated.
Wes
#4
Confusing post.... when you checked the coil, was there spark, or wasn't there? Since you say you have "no spark", it would appear you checked the resistance and it was OK, but there is no spark... but its not clear from your posts.
#7
Sorry I was not more clear,
There is no spark from the coil. The coil and coil wire test fine. I also have proper voltage to the + side of the coil. I had no spark to the plugs, or out of the coil before or after I put in the new distributor assembly. Obviously the old distributor was not at fault but it seemed like a good place to start eliminating problems since thy are so prone to failure. The new distributor came assembled with new cap and rotor. I am questioning if there could be some thing with the PCM, wiring, or possibly a previously installed alarm system that could be shutting it down. I have had the car to + 90 MPH before with no problems, but once it started shutting down @ 90, it did it every time. I am not aware of any alarm system on the car other that the factory VATS system. I did have trouble with that a few months ago, but I bypassed it with a resistor under the dash and have had no problems with it since. When I did have trouble with the vats, it just would not crank. As I understand, the vats will only prevent cranking and it can disable the injector pulse. I have no problems with either one of these.
There is no spark from the coil. The coil and coil wire test fine. I also have proper voltage to the + side of the coil. I had no spark to the plugs, or out of the coil before or after I put in the new distributor assembly. Obviously the old distributor was not at fault but it seemed like a good place to start eliminating problems since thy are so prone to failure. The new distributor came assembled with new cap and rotor. I am questioning if there could be some thing with the PCM, wiring, or possibly a previously installed alarm system that could be shutting it down. I have had the car to + 90 MPH before with no problems, but once it started shutting down @ 90, it did it every time. I am not aware of any alarm system on the car other that the factory VATS system. I did have trouble with that a few months ago, but I bypassed it with a resistor under the dash and have had no problems with it since. When I did have trouble with the vats, it just would not crank. As I understand, the vats will only prevent cranking and it can disable the injector pulse. I have no problems with either one of these.
#10
The cutting out at 90mph seems strange. Did you check to see if the ICM is getting a signal from the opti??
http://shbox.com/1/4th_gen_tech2.html#opti_test
http://shbox.com/1/4th_gen_tech2.html#opti_test
#12
The cutting out at 90mph seems strange. Did you check to see if the ICM is getting a signal from the opti??
http://shbox.com/1/4th_gen_tech2.html#opti_test
http://shbox.com/1/4th_gen_tech2.html#opti_test
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