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what can cause a car to miss?

Old 04-23-2003, 03:02 AM
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dualblade
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Post what can cause a car to miss?

i think my car is missing a bit. can any of you guys describe what a miss feels like so i can verify? also, what are the possible causes?
Old 04-23-2003, 03:19 AM
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GOBOGIE
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I believe that mostly it is an intermittent cutting out of power. Causes? There are many:

- bad spark plugs
- bad plug wires
- clogged injector or getting clogged
- vacuum line(s)
- bad fuel filter
- bad fuel pump
- This would be very bad, but an intermix of coolant and oil caused by a bad head gasket or bad oil cooler seals... both will cause some white exhaust and condensation on the underside of the oil cap (easy one to rule out)

There's a few, anyone else want to add to the list?
-
Old 04-23-2003, 06:16 AM
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Legoland951
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The list is a mile long. Air flow meter adjustment, bad airflow meter, vacuum leak in many possible places, cap and rotor, bad ground or connections to the injectors, one slightly bent valve, worn cam, bad lifter, low compression in one cyl., etc. Take it to someone who knows how to read the spark plugs for that the plugs never lie. Then put it on diagnostic machines to check for electronic functions, fuel pressure, exhaust emissions, and computer codes for any other possible problems. You will have to be more specific about the symptons. The best thing to do is to replace things that already are due for replacement because you can kill 2 birds with one stone.
Old 04-23-2003, 02:12 PM
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dualblade
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ahh good to see it's one of those easy problems to fix <img border="0" title="" alt="[Wink]" src="wink.gif" />

things that are new within the last year:
plugs
plug wires
air filter
fuel filter
cap
rotor

i think my car's always had this problem, just took a friend to notice it. feels like the car hiccups every once in a while especially at idle

i have no reason to think it's headgasket because i haven't seen any coolant/oil mix. i guess that leaves vaccuum, fuel pump, and injectors.

how would i go about testing the fuel pump? would the miss be caused by uneven, too much, or too little fuel pressure?

with the injectors, could i have them cleaned by a local place like pep boys or is that a bad/ineffective idea?
Old 04-23-2003, 02:33 PM
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billybones
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Easy thing to do is take it to a shop and throw it on a scope... Cost is little and will keep you from just shot gunning it. Just my opinion.
Old 04-23-2003, 03:08 PM
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Jeff928S4
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S2??? Hummmmmm,

I'll ask my question I always ask.....

Do you have hood insulation?? If there is no hood insulation, even new wires can jump spark off the hood. There was a warning in the manual about it, specifically the 944S and S2.

944S Boyeee


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