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STILL diagnosing my no start

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Old 02-05-2012, 06:28 PM
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strtsol1109
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Default STILL diagnosing my no start

soo im back to no start, fuel spark and air is good, new dme relay, new blaster coil. the new issue im having is when im cranking the car im getting a sizeable spark from below the TB near where the turbo is... Is there a ground there or maybe some kind of electronic?
Old 02-05-2012, 06:43 PM
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odurandina
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this is the most unanswered question on Rennlist. and why you buy a 968.
Old 02-05-2012, 07:57 PM
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944CS
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Originally Posted by odurandina
this is the most unanswered question on Rennlist. and why you buy a 968.
A 968 will soon have the same problems, once these cars reach a certain age certain things deteriorate


Biggest cause for no start on 944's/951's is speed/reference sensors or the harness - usually if it's the harness this happens after some work was just performed that causes you to have to move the connections - underneath the plastic sheathing, the wires are hard and brittle and crack. Easy to diagnose with a multi-meter

to the original poster, was this car sitting for a long time? When you say you have fuel, how do you know? What are the compression numbers?
Old 02-05-2012, 08:20 PM
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strtsol1109
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it was my dd for 3 months, been sitting for a month with a no start, trying to start and dying immediately. I bought a LR fuel pressure gauge and its normal pressure for my 3 bar fpr, tach bounces so its not the reference sensors and the spark im talking about isnt coming from there, its come from right past the j boot where u cant really see anymore... is there a ground there maybe?
Old 02-05-2012, 10:03 PM
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944CS
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no ground there but the alternator is under there, maybe you have a bad power connection there
Old 02-05-2012, 10:18 PM
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strtsol1109
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do u think that would cause a no start?
Old 02-05-2012, 11:27 PM
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What do you know about the TB belt. I always like to get rid of the worst things first. I would make sure it has not skipped a tooth or something else.
Old 02-06-2012, 10:29 AM
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944CS
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Originally Posted by strtsol1109
do u think that would cause a no start?
Yes it's possible but the fact that you are seeing a spark in that area is not normal, you should check it out - removing the airbox and AFM, the car will still try to start, so I would remove those two things and try to start the car at night without any lights around so you can see exactly where the spark is coming from.
Old 02-06-2012, 12:50 PM
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im about 98% sure its not the timing, i played with some vac lines and electrical connections cleaning them up and what not last week and the car started drove around for a mile just fine so i thought i fixed it, went to leave in the am for work backed out then it died and back to the no start..
Old 02-06-2012, 01:01 PM
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odurandina
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Default not even close.....

Originally Posted by 944CS

A 968 will soon have the same problems, once these cars reach a certain age certain things deteriorate...

i've heard this theory before. but the truth is, our 968s are already old. they ARE NOT plagued with the constant electrical problems seen in the 944s. just the same as the late '90s Chryslers have far fewer problems than the late '80s Chryslers. the truth is, these problems with the 944s where already happening 15 year ago. the 968 is a better car.

these issues would have already started to appear in the 968s.

but, they're not.

let's have this conversation again in say, 5 years. i'll be telling you the same thing.
Old 02-06-2012, 02:50 PM
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Hollywood D
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Start pulling things off and look for a loose of frayed wire. Based on the 'spark' you're seeing I would guess it some kind of short. But I'm no electrician.
Old 02-07-2012, 12:01 AM
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I am having this same problem with my 944 na. I disconnected the hose from the ICV to the Intake boot and sprayed carb cleaner down it leading to this ICV. Let it sit for a hour and it started up. Im planning on removal of the ICV, and recleaning of this item and maybe lub it with a bit of WD 40. Good luck with your car.
Old 02-07-2012, 10:06 AM
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1) Are you getting good steady spark from the coil wire while turning the starter over?
2) What is your fuel pressure while turning the starter over?
3) Are you getting a 12V pulse at the injector plug?
Answer these questions correctly with no guessing or speculating and you can determine your problem easily.



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