Mechanics

I'M GETTING NO SPARK FROM THE COIL. WHERE SHOULD I LOOK FIRST.

1994 Dodge Dakota • 190,000 miles

My 94 Dodge Dakota with the 3.9 died on me and with 2 exceptions will not restart. I have had no previous problems with this engine. The 2 exceptions that it did restart it ran normally. It did die once the second time I turned it off. The engine just spins over. There is no spark from the coil but I have not yet checked for power to the coil. The on-board diagnostics give me a code 32 and a code 42. I have read every thing from a notorious 3 into one pigtail corroding to the crank shaft sensor. Are there test I can perform to narrow this down instead of just tossing out cash for unneeded parts?
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Low down
September 16, 2012.



Hard to do testing without a scan tool to verify crank sensor reading. It is the most common failure for this condition. Try removing the connector and looking for corrosion.

Roy

ASEMaster6371
Sep 16, 2012.
Hi guys. Check for voltage at the ignition coil primary "+" wire, any injector, or either small wire on the back of the alternator. You should see 12 volts there for one second when you turn on the ignition switch and you might hear the fuel pump hum too for that one second. What's important is if that voltage comes back during cranking. If it doesn't, suspect the crankshaft position sensor just mentioned.

Code 42 is related to something shorted on the line coming from the automatic shutdown (ASD) relay that feeds the ignition coil, fuel pump, and injectors. The clue there would be there's no 12 volts to those items for that first one second when you turn on the ignition switch. That is best tested with a test light. Most digital voltmeters don't respond fast enough for you to see that voltage.

You might try swapping the ASD relay with a different one like it. They don't fail very often but you don't want to overlook something simple.

Caradiodoc
Sep 21, 2012.