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924/931/944/951/968 Forum Porsche 924, 924S, 931, 944, 944S, 944S2, 951, and 968 discussion, how-to guides, and technical help. (1976-1995)
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All Crank No Fire

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Old 10-21-2008 | 08:29 PM
  #31  
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Since Pete's tied down tonight with the GF unit...

We did a flyby 15 minute troubleshooting effort:

Fuel flow: check
Re-inspect cap and rotor: check
Pull injector plug and check for voltage on ignition attempt: FAIL

Interesting.

Testing his coil in my car for kicks. Give me 20. Make that 45... boss just announced my Fatherly duties for the evening...
Old 10-21-2008 | 09:10 PM
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Your coil is fine man... There's a savings right there.
Old 10-22-2008 | 11:22 AM
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Originally Posted by 75ohm
Since Pete's tied down tonight with the GF unit...

We did a flyby 15 minute troubleshooting effort:

Fuel flow: check
Re-inspect cap and rotor: check
Pull injector plug and check for voltage on ignition attempt: FAIL
Noid light time. And while you're in your car, you might want to rip the DME out to put in his
Old 10-22-2008 | 11:39 AM
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Spare DME going in tomorrow, with new plugs and wires...

Old 10-22-2008 | 11:55 AM
  #35  
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Check to make sure you are getting fire from the coil and fuel pressure in the rail.You need to figure out what you are not getting,fire,fuel or air!
jamie@944online.com
Old 10-22-2008 | 12:58 PM
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Originally Posted by DarylJ
Noid light time. And while you're in your car, you might want to rip the DME out to put in his
Ok, do this check; take an exacto knife and open the boot of each injector plug... you will likely find the wires are bare and shorting. This will be more likely if you have R&R'd the injector plugs many times or the wires leading to the injectors are kinked and stressed. THIS WAS MY NO START PROBLEM and it was fixed by replacing ALL 4 injector plugs (all 4 were crap.) Sadly, I "fixed" all kinds of stuff before discovering the actual problem... I've written this here before, but no one seems to take my word to check this... oh well...

BTW, you can tease the wires apart and crank the car to see if the fix works, before doing any soldering. If any one of them is shorted, it wont work though, so you have to check all 4 to be sure.
Old 10-22-2008 | 03:04 PM
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We did have one bad injector wire last time we had problems related to bad FPR.
Old 10-22-2008 | 03:24 PM
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I recall, but that wouldn't keep the engine from starting this go...
Old 10-22-2008 | 03:53 PM
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OK. Let's swap the DME and git 'er done!
Old 10-22-2008 | 04:12 PM
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Tomorrow it is.
Old 10-22-2008 | 05:11 PM
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I want to drive the car to work Friday.
Old 10-22-2008 | 05:30 PM
  #42  
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Game on.
Old 10-22-2008 | 06:22 PM
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DME...mine was the same thing...even bought a nother off ebay...when that didn't work i spent a month replacing parts till i voltmetered both sides of the DME and found signal going in...no signal coming out. new DME later popped right off...then started on fire. but it still started!
Old 10-22-2008 | 08:47 PM
  #44  
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Just in case, anyone have an '86 NA DME?

944.618.121.04 is what PET calls for -87.

Thanks.
Old 10-22-2008 | 09:59 PM
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Giddy with anticipation....


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