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Missing problem... Need Diagnosis and Thoughts!!!

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Old 03-23-2009, 09:28 PM
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Missing problem... Need Diagnosis and Thoughts!!!

This problem has been on my nerves for a couple months before i put the car away for storage and i just pulled it out today so i would like to get this problem solved. The problem im having is as soon at the engine gets to operating temp and the fans kick on the idle goes to crap and the engine seems sluggish like its got a bad injector or something is up. Its not misfiring likes it rough it just doesnt act like it does when cold when i rev the engine when cold its clean and crisp and soon as its warm its sluggish and doesnt feel like its running properly. I replaced the opti, icm, and coil last year and its doing the same thing but thats a totally different story there but i know theyve been recently replaced. I have been told it could possibly be my coolant temp sensor on the waterpump thats shot and isnt giving a reading to the pcm when it gets to operating temp and causing it to go lean or rich and make my car run like crap. That and my gas mileage has been out the window aswell ever since so i know its not running the greatest. Can anyone point me in the right direction? I plan on picking up a coolant temp sensor tomorrow so see if that will fix the problem as there are cheap.

Any thoughts???
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Old 03-23-2009, 09:42 PM
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Have you ever scanned it for codes? The fans will come on when certain trouble codes are active.
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Old 03-23-2009, 09:50 PM
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just the guy i was hoping for... i havent checked for codes yet and there is no light on the dash. Its just when the car gets to op temp it runs lean or rich cuz like i said it runs perfect when its cold.
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Old 03-23-2009, 09:52 PM
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more leaning towards the coolant temp sensor or an egr problem one of the two.
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Old 03-23-2009, 09:53 PM
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Not all trouble codes turn on the SES light. You replaced all those parts, and never scanned it? Given the description of the symptoms, a data log would problably provide the most insight to the problem. Consider Freescan or Datamaster software. Free software - all you need is a laptop and a cable.
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Old 03-23-2009, 10:13 PM
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my opti crapped out on me last year so while i was in there i replaced the icm and coil while i was at it to hopefully cure anymore problems. while replacing them the miss was still there is all i was trying to describe.
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Old 03-24-2009, 05:35 AM
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closed loop problem. Check the O2 wiring especially considering you have long tubes. Pull the foil wrap off the wires going down the inside of the passenger fender if it hasn't been relocated.
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Old 03-24-2009, 06:43 AM
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its on my formula not the t/a... stock manifolds at the moment.
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Old 03-24-2009, 12:27 PM
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I'd start looking at heatsoak sensitive electronics and closed loop-only sensors

my first guess would be bad o2's
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Old 03-25-2009, 05:34 AM
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Originally Posted by 95mysticta
its on my formula
Anything else you forgot to mention?

And what is this?
"AS&M Coated 1 3/4 Mids"
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Old 03-25-2009, 09:03 PM
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headers arent on yet... still in the box i just got the car out of storage. i had to etest it yesterday and it passed and it wasnt like it was really close either. i was worried cause of the miss it would either run to rich or lean and cause it to fail. ill have to start testing.
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Old 03-27-2009, 05:31 AM
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pretty easy to figure out if it's a closed loop issue. Un plug one of the O2s and try it. If it's ok then, it's a closed loop issue cause unplugging an O2 forces it to stay in open loop.
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