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Engine Dies After 15 Seconds

 
Old 10-07-2010, 05:06 PM
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LGL
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Default Engine Dies After 15 Seconds

Hot or cold, engine runs smoothly for about 15 seconds then dies. I can keep it running with throttle. On the road, engine RPM varies widely at constant throttle and dies at idle. Help. Problem occurred soon after the following: timing belt/WP replacement, pod removal and refurbishment, throttle arm to throttle came off at throttle when I disconnected the front ball connection. Help!
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Old 10-07-2010, 05:14 PM
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Leon Speed
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Originally Posted by LGL View Post
On the road, engine RPM varies widely at constant throttle and dies at idle.
Varies how?
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Old 10-07-2010, 05:15 PM
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Sounds like a rather nasty vacuume leak to me. I love those wheels in your avatar by the way. What are they? Where did you get them and how much? Sorry for the 100 questions but I do like them. Beautiful car. You are not too far from me. We will have to meet up some day. Also there is a very active group of 928ers in Richmond. Good luck on getting this thing running.
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Old 10-07-2010, 05:16 PM
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Tries to go to zero then picks back up again. Always begins at 15 seconds after engine start.
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Old 10-07-2010, 05:23 PM
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Thanks Frank,
The wheels are Victors and were about $300 each.
Grant
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Old 10-07-2010, 05:41 PM
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I was thinking O2 sensor first because of the timing issue but 15 seconds is too short and don't know if yours has one. Can it be that you misaligned the throttle somehow when disconecting the front ball connection (why was this btw?).
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Old 10-07-2010, 05:52 PM
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Is your idle switch working ?
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Old 10-07-2010, 06:25 PM
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Originally Posted by jon928se View Post
Is your idle switch working ?
Search "Idle Switch" "Hunting" "ISV"
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Old 10-07-2010, 06:29 PM
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Originally Posted by jon928se View Post
Is your idle switch working ?
Good place to start
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Old 10-08-2010, 08:42 AM
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Thanks Steve. I did the search before posting and tried the O2 sensor fix that the guy with a similar but 75 second interval till the symptom used w/o success. I'll try some visual inspections this weekend. My tach also quit working after my pod repairs so I'm going to try to learn about how the RPM limiter works. The only good news is that all my trans position lights work again and I now have a PK Tensioner and the new designed water pump installed.
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Old 10-08-2010, 09:29 AM
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PS:

A quick visual found half the top of the water temp sensor missing that feeds the EZF and LH computers. I'm not sure which is broken because the wire appears to be blue/yellow which is different from my diagram. Does anyone know if that could cause my problem ?
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Old 10-08-2010, 11:20 AM
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I think you are describing the Temp II. It's on the front bridge just to right of oil filler. That sensor does feed temp to the computers, needs to be functional.
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