Fifth cylinder misfiring

Tiny
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  • CHEVROLET IMPALA
I purchased 2004 chevy impala 2 weeks ago and 2 days ago I had check engine light coming on when I checked code it said fifth cylinder misfirind dealer told me that they did 133 point inspection on the car before selling it I was wondering if anyone would know what the problem is car is running same only have little problems starting it takes couple of seconds before it cranks up thanks in advance for your help
Tuesday, August 28th, 2007 AT 12:05 PM

11 Replies

Tiny
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Engine size. Miles?

Anyways, the 133 point check up does not mean they repair anything on the list, but is checked. The sales manager makes the calls on what to repair.

HAve a compression check done, the 3.4 motors are common for intake gasket leaks.

Any warranty?
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Thursday, August 30th, 2007 AT 8:36 AM
Tiny
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Current milles are 63420 engine size is 3.4l but I don't have any warranty I heard that chevy gives 100 000 warranty on engine im not sure if thats true car still runs great only problem if that is problem is when im starting up it takes couple of seconds I thought of doing tune up would that help thanks in advance
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Thursday, August 30th, 2007 AT 6:26 PM
Tiny
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Is the starting problem only after it sets? Typical of a bad fuel pump not holding pressure in the lines.
Trun the key to the on position and let the pump run, shut the key off for 5 secs and back to on until pumps stops again. Do theis 3-4 times and then crank. Does it start right up now?

As far as I know the 2004 3.4 motor is 36,000 mile warranty.

A fuel filter and an air induction service cetainly would be smart, but I highly doubt the wires or the plugs are bad. The plugs are double platinum and I see these going 100,000 like they claim.

If you are question a plug or wire, you can swap them to a different cylinder and see if the miss moves.
I am more curious as to the test I suggested.
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Thursday, August 30th, 2007 AT 7:24 PM
Tiny
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Ok I will try that and im gona let u know what the result is probably any time tomorrow
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Thursday, August 30th, 2007 AT 9:22 PM
Tiny
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Ok I will try that and im gona let u know what the result is probably any time tomorrow[/quote:3e3919f7a7]

tryed that test and it seems that car starts better so if that is problem what does that have to do with cylinder misfiring and if it does how do I fix that I am on tight budget im suprised I thought if I had mechanical problem that would show on message centar but so far it dosent says anything well thanks in advance I hope its not fuel pump that thing is with instal around 500 bucks
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Friday, August 31st, 2007 AT 4:12 PM
Tiny
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Pretty sure the fuel pump bit it. Like I said, "Is the starting problem only after it sets? Typical of a bad fuel pump not holding pressure in the lines. "
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Friday, August 31st, 2007 AT 10:54 PM
Tiny
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Yeah it figures its something expensive is it ok if I keep driving or do I need to change it right now or maybe just maybe there is cheap way to make it work and how do I get rid of check engine light sorry for not answering sooner but I was busy at work happy hollydays
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Monday, September 3rd, 2007 AT 6:41 PM
Tiny
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It depends on how bad you want or don't want to put yourself in a postion of being stranded. The extra cranking will wear on the starter.

What we don't know is that the po305 code is definitly related to the fuel back flow problem. IF it was my car, I would be concerned about a possible intake gasket and check the comprssion of that cylinder. OR verify the pump problem and very closely monitor the CEL afterwards.
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Tuesday, September 4th, 2007 AT 2:20 AM
Tiny
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Hi sorry it took me this long to answer but I was so busy working I have a question I noticed that my car is using way to much gas could that be directly reason of fifth cylinder misfiring but I dont smell gas anywhere so im not sure thanks in advance
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Wednesday, September 12th, 2007 AT 3:27 PM
Tiny
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Yes that may be the case, but I wouldn't put off verifying it. Pull the plug on the fifth cylinder and see what it looks like.
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Wednesday, September 12th, 2007 AT 3:31 PM
Tiny
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I will do that whats strange check engine light went off and didnt come on still am I that lucky that it fixed itself or is that sign that it will die soon heheeh hopefully not
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Thursday, September 13th, 2007 AT 1:28 PM

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