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Help! Just turned off when driving

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Old Feb 24, 2012 | 03:30 PM
  #1  
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From: Bozeman, MT
Year: 1997
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Engine: 4.0 inline 6
Default Help! Just turned off when driving

Was driving everywhere last night no problems then this morning get going and she just stops at the first light I hit the breaks and she turned off now it'll turn over but seems like no spark or anything any suggestions
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Old Feb 24, 2012 | 03:43 PM
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Year: 1997
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I think it's the fuel pump but not sure
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Old Feb 24, 2012 | 03:47 PM
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Spray some starting fluid into it and see if it fires and dies or doesn't fire at all.
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Old Feb 24, 2012 | 03:56 PM
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I would also look into the tps. Mine was doing the same thing and was not shifting into OD. It would turn off three times after a cold start.
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Old Feb 24, 2012 | 03:58 PM
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Well it's not the pump that's working fine ...
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Old Feb 24, 2012 | 04:07 PM
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Crank position sensor?
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Old Feb 24, 2012 | 04:14 PM
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How do you check that
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Old Feb 24, 2012 | 04:19 PM
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Unplug it from the harness and probe A and B (on the CPS side, not the harness side) with a multimeter set to AC volts (yes, AC). With the engine cranking (it won't start) you should read 0.5v AC. Anything under ~4.5 and your CPS is suspect.

Also, just unplugging and replugging sometimes clears the issue.
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Old Feb 24, 2012 | 04:21 PM
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You could just check for spark as well, whatever technique you prefer as there are many. Starting fluid in the throttle body, tongue on spark plug wire (<<<that's a joke, don't do that), pull a plug and ground it while cranking, probe the coil... like I said, lots of ways.
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Old Feb 24, 2012 | 04:29 PM
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ignition coil, same thing happened to me a while ago, also a 97.
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Old Feb 24, 2012 | 04:39 PM
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Originally Posted by F1Addict
Unplug it from the harness and probe A and B (on the CPS side, not the harness side) with a multimeter set to AC volts (yes, AC). With the engine cranking (it won't start) you should read 0.5v AC. Anything under ~4.5 and your CPS is suspect.



Not sure a 97 checks the same way our old Renix rigs do....

Also, just unplugging and replugging sometimes clears the issue.
Good idea.
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Old Feb 24, 2012 | 06:12 PM
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I approach every no-start in the same way.

First, check for spark.

Pull a spark plug. Keep it attached to the plug wire. Place the plug electrode near a good engine ground. Have a buddy crank the engine while you watch. You are looking for a strong, BLUE, snapping spark. Yellow/orange/white indicates a weak spark, which may not be strong enough to start the engine.

If spark checks out (and only IF), try a small splash of gas into the intake or a small shot of starting fluid. If the engine starts and runs for a little bit using this technique, you have identified a FUEL DELIVERY problem.

The above two tests are quick and dirty but are extremely valuable in isolating root cause here.

Do NOT throw parts at this on a hunch. You will likely be wrong and your pocketbook will suffer for the guesswork. Test your way to a solution here.

Good luck and keep us posted!
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Old Feb 24, 2012 | 06:19 PM
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Same happened to one of my 88s. Someone had added a 2ft extension to the CPS for some reason and it was wrapped around the front driveshaft...
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Old Feb 24, 2012 | 06:57 PM
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Found out its the cps for sure got one with a lifetime warranty for 85 not bad will throw it in tomorrow and hopefully take her out as well
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Old Feb 24, 2012 | 07:01 PM
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Originally Posted by jeep4lf
Found out its the cps for sure got one with a lifetime warranty for 85 not bad will throw it in tomorrow and hopefully take her out as well
Awesome, I was hoping that first post wasn't broken down on the roadside!
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