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jjklongisland
08-05-2014, 04:06 PM
Okay, still cant get my car started. I have no spark. It just cranks. How can I test to see if its my ICM/DIS (also, is the DIS and the ICM the same thing). Rock auto sells a new ICM for $100. This car is really starting to piss me off... Any suggestions?

KMT
08-05-2014, 04:12 PM
Okay, still cant get my car started. I have no spark. It just cranks. How can I test to see if its my ICM/DIS (also, is the DIS and the ICM the same thing). Rock auto sells a new ICM for $100. This car is really starting to piss me off... Any suggestions?

I think you've already seen the no-start troubleshooting link... http://mnharms.com/tutorials/disnostart/

Some auto parts stores say they can test a DIS, but I've found it's better to swap one out with a known good unit so the car is part of the mix.

Les Borda
08-05-2014, 04:17 PM
Yes on rockauto the ICM is the same thing, try to get the Motorcraft one. I have hear Airtex is iffy and the Standard Motor Products is who knows.

S_Mazza
08-05-2014, 04:19 PM
With no spark, it's probably the crank sensor or associated wiring.

There is a "Crank No Start Troubleshooting Guide" somewhere on this site, posted by one of our members. It's based on some shop manual info, I think.

Just as a basic suggestion, if you get an LED 12V test light (which reacts fast enough to show pulses and which won't be fooled by weaker voltage), you can test for pulses on the primary side of the ignition coil connector while cranking. No pulses there means no input from the DIS.

But the DIS can't pass through input it never receives from the crank sensor.

Many parts stores have testers that will test a DIS module under load, which is in theory the next best thing to testing on the car. However, I know they can sometimes pass a module that won't work on the car.

Les Borda
08-05-2014, 04:25 PM
Is yours a 5 speed? If it is and it's a bad crank sensor the upshift light will stay on while cranking.

jjklongisland
08-05-2014, 04:58 PM
Thanks guys... So it is either the crankshaft position sensor or the DIS... I changed the camshaft sensor a few weeks ago since it wouldnt start when hot. That fixed it and now this... It drove good for a week or so. Last weekend I tried to start her and she cranked for a real long time. I almost gave up and she then fired. I then let her warm up and shut it and started it a few times and seamed good. I went to pepboys for some more vinyl paint and had no issues and parked her back in the driveway. Next day she wouldnt start at all... My car is an 89 5 speed but I have never scene a shift light on my dash. Either the bulb is out since I got it or mine doesnt have one. KMT, thanks for the link!

bowez
08-05-2014, 05:02 PM
Sounds like DIS/ICM to me. If you take to parts store for test ask them to do multiple ones back to back.

My last module took 3 runs to get a fail on the machine and it had already failed according to the "No start page".

Les Borda
08-05-2014, 05:05 PM
It has it all the 5 speeds do unless it was converted from an automatic, the bulb may be burned out behind it. It's a sure sign the crank sensor is pooched