No spark
#1
No spark
My 5.7 TBI will not start. Please forgive me guys its in a 87 GMC but I was told you guys can help me out.
I have no spark at the coil. Here is the results of my testing. I am just about out of ideas.
-ECM-A,ECM-B,IGN fuses all good
-Have 12v on the pink wire going to distributor.
-Have full voltage on the tach wire (not internally shorted)
-Tested coil according to service manual. Passed but changed it anyway with new.
-Ignition module was changed with GM new. Old one tested OK
-Tested pick up coil. 850 ohms. Pass.
-For giggles changed computer with another 5.7 7747.
The only thing I still have to check is the 4 wires from the distributor to the ECM. I think this is unlikely though.
I have no spark at the coil. Here is the results of my testing. I am just about out of ideas.
-ECM-A,ECM-B,IGN fuses all good
-Have 12v on the pink wire going to distributor.
-Have full voltage on the tach wire (not internally shorted)
-Tested coil according to service manual. Passed but changed it anyway with new.
-Ignition module was changed with GM new. Old one tested OK
-Tested pick up coil. 850 ohms. Pass.
-For giggles changed computer with another 5.7 7747.
The only thing I still have to check is the 4 wires from the distributor to the ECM. I think this is unlikely though.
#2
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Car: 85' Trans Am !best car ever!
Engine: 305tpi 215hp LB9 two bolt,
Transmission: th-700r4
Axle/Gears: stock (3.27)
Re: No spark
if you have no spark, did you check your batt wire to dizzy with ignition to on. and if youre no spark, try pulling the spark wire and and turn over the wire next to a ground point. to see an actual spark. if its blue its good. sometimes the the fuel pump can fail on you, check to see if you got about 8psi ya report back
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