# Engine or Tranny Problem



## coupe81 (Jun 6, 2010)

Hey everyone, I have 2002 Nissan Altima 2.5 S with an automatic tranny. The problem I'm having is that occasionally it starts acting up especially in Overdrive or Reverse. It will start bucking/jerking at part throttle in overdrive recently and the check engine light will flash. In reverse, once in gear, it will bog down and buck/jerk then it will finally take off. I had this problem before which started like this and it got worst by shutting off on the highway. I had taken it to the dealer and they had updated the computer which help. I had also replaced the both CPS, changed the plugs, and three coils.This happen to me about 10K miles ago before. Could it be one of the CPS again since I went with an autozone part? Could it be a tranny problem? I haven't change the fluid since I got the car which was at 59K miles, I currently have 150K miles but the fluid is still bright red and doesn't smell burnt or any metal shavings. It's my daily driver so it has many highway miles.


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## smj999smj (Jan 1, 2006)

I would have the trouble codes retrieved before I would do anything else.


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## coupe81 (Jun 6, 2010)

smj999smj said:


> I would have the trouble codes retrieved before I would do anything else.


I get no codes.


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## smj999smj (Jan 1, 2006)

Sounds like an ignition system issue by your description.


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## heathman (Sep 13, 2010)

I think that the V.S.S (vehicle speed sensor) in the trans should be checked with a scope for proper operation ... Good Luck !!


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## smj999smj (Jan 1, 2006)

The thing that would steer me away from the VSS is that it wouldn't cause the check engine light to flash, indicating a severe misfire that could be detrimental to the catalytic converter. There should be a stored code after this happens.


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