Mechanics

CAR WON'T START

1997 Jeep Grand Cherokee • 4.0L 6 cylinder RWD Automatic • 126,000 miles

My engine will crank but there is no spark. I have replaced the ignition coil, distributor, cap, rotor, plugs, crank sensor and cam sensor. I have tested the fuel pressure, asd relay, starter, battery, alternator, all the wires and fuses, and all the relays. The ecm was replaced in Sept of 2012 so that should not be the problem. I am at a complete loss as to what the problem could be.
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Sxayasone3
March 21, 2014.




Step one is to determine if the automatic shutdown (ASD) relay is turning on. Measure the voltage on the feed wire to the ignition coil or any injector. You should see 12 volts there for just one second after turning on the ignition switch. What's important is if it comes back during cranking. If it doesn't, we have to look at the cam and crank sensors.

Caradiodoc
Mar 21, 2014.


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