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Q: Engine cranking but no spark (no trigger signal )

asked by on

My car shut downed on the road and towed to home and trying to find the problem,

Pls refer to the followings

Replacement spark plug / fuel filter & relay Tired to replaced crank sensor 2 times Replacement 1 brand new ignition coil for the testing Changed the engine oil & filter

3 wires of ignition coil detail as following

1......... + voltage is good 12v 2......... Ground is good

3....... No trigger signal

Could you give me some advise ?

Your support will be highly appreciated.

THANKS

My car has 125000 miles.
My car has an automatic transmission.

A: Hello and thanks for contacting YourMechani...

Hello and thanks for contacting YourMechanic. The trigger for your ignition system lies within the computer system. Your computer is not allowing the ignition to trigger the power. The coil should have power to it and a ground wire. The ground wire goes through the harness back to the computer. The computer then rely's on the camshaft and crankshaft position sensors to create a timing for the trigger.

Check the crankshaft and camshaft sensors to see if the are plugged in. Look at the harnesses to see if there are any debris or corrosion. Use a digital volt meter to check the resistance on the camshaft and crankshaft sensors. I recommend replacing the camshaft and crankshaft sensors if they have no resistance on them. If you have resistance or you replaced the sensors and you are still having no spark, then you would need to have your computer flashed or replaced. Either way, if you are in need of help getting a precise diagnosis, a certified professional from YourMechanic can come to your car's location to inspect the starting issue and proceed with the proper repairs.

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