Question about 1999 Mercury Cougar

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99 mercury cougar wont idol until car is warm p0420 codes came up

I have a 99 mercury cougar it is fairly cold and the when i go to start the car in teh morning it starts fine and idols fine but about 5 min later its starts to chug and eventually idols down till it shuts off. also when i get to a stop sign it will start chugging and idoling down. the check engine light hase been on i got a p0420 code from it and dont no wat to fix. anyone no wat the problem could be

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  • jakeshumway Feb 10, 2009

    my 1999 cougar will start and run for a couple minutes but them the engine cuts off, i don't lose power and it will sometimes start back up for a couple seconds, when i rev the engine this is not a problem but when my foot is off the gas the engine just quits, what would cause this?



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Hello, here is a thread I found on this site with from what it looks like, the same problem(with an added solution) that you have.

Posted on Jan 30, 2009


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