1999 Saturn SL1 rough idle at start up and stalling

1999 SATURN SL1
123,000 MILES • 4 CYL • FWD • AUTOMATIC
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DWBROWNEYE
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Engine sounded as if running on 2 or 3 cylinders when starting cold. Replaced plugs, wires, Airfilter. Ran better but still had problem on cold start. Tech cleaned throtle body, adjusted idle speed, found no codes on computer. Still having issues. ANY IDEAS?


Thanks
Dave
Oct 29, 2010 at 8:15 PM
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SATURNTECH9
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SO does it only run bad when it's cold?You should never adjust the idle screw there factory set and in over 16yrs of working for saturn i have never adjusted one.
Oct 29, 2010 at 8:35 PM
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DWBROWNEYE
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Yes, Seems to be only when cold. It starts, running rough, rev the engine once or twice, it smooths out and seems to be fine. it was suggested we try a can of fuel injector cleaner.
Oct 29, 2010 at 10:10 PM
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SATURNTECH9
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Dirty injectors won't do what your expernicing it sounds like a bad coolant temp sensor really common on those cars.There only like 10 make sure you get a brass tipped one the plastic tipped ones crack.Make sure you check the connector going to it if it's corroded you will need to replace it too.
Oct 30, 2010 at 12:36 AM
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DWBROWNEYE
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I see, are you talking Air Temp Sensor, or Coolant Temp Sensor? Is this located in the breather box?

Is this interchangeable with the coolant temp sensor?

We just replaced the transmission fluid sensor about a month ago.

Thanks
Dave
Oct 30, 2010 at 9:01 AM
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SATURNTECH9
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Like I said in my last post coolant temp sensor it's screwed into the cylinder head below where the upper radiator hose goes onto the head.There only like 10 the same sensor you put in the transmission.Let me know how it runs after you change it.
Oct 30, 2010 at 10:01 AM
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DWBROWNEYE
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Louie,
I fumbled around this morning and managed to remove the connector without damage, removed the sensor, (plastic tipped) which appeared damaged.

Car started right up no skipping,

I'll have to let the judge ( daughter) check it out.

I'll let you know

Thanks

Dave
Oct 31, 2010 at 7:43 AM
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SATURNTECH9
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Alriight let me know how it run's sound's like it should run good now.
Oct 31, 2010 at 10:08 AM
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DWBROWNEYE
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2 very cold mornings and all seems well.

Thanks a bunch!!

dave
Nov 2, 2010 at 6:45 PM
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SATURNTECH9
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Your welcome glad to hear you got it fixed that's what were here for to help people fix there cars.
Nov 2, 2010 at 10:42 PM