Check Engine Soon Light Is On. Please Help!!!

My wife has a 2002 Nissan Altima 4 cylinder. Sunday she called and it wouldnt start. She said that she had driven it earlier that day, but it wouldn't start when she was ready to come home. She said that her grandpa got it to start by waiting a few minutes and just starting it right up. She said that upon starting there was a lot of white smoke coming out. It hasnt happened again and it hasn't smoke at all and it is driving perfectly fine, but the check engine light is on. Any ideas?

Thanks in advance.

If any help, whenever I remove the gas cap you can hear a lot of air pushing out of the tank as well as a gargling noise that will stop after a short period.

You need to find out what code is turning on the check engine light. Go to a local Auto Zone, they will give you a free read out and post the code here.

I went to advance auto today and they plugged in the computer. I forget the code though. It was something like P0420.....anyway it was the code for the catalytic converter. Apparently, it is not working as well as it should be. He said that its not something that we need to run out and fix tomorrow though. He priced the direct bolt on catalytic converter at $228 w/ 5yr/50,000 mile warranty. As soon as I find a trustworthy shop we will get it installed. We are looking into getting it done this weekend. He said with the part and installation it shouldnt be anymore than $350.

$228 sounds a little cheap, never priced out aftermarket cats though. The cat convertor for the 420 code is not a "bolt on" . It's made inside the exhaust manifold, meaning you have to replace the whole thing. Did you happen to see the part?

I didnt get to see it. The guy went in to his PC and pulled up catalytic converter and gave me a price. After reading around a little I seen that there is an ECM update that may help solve the problem. I will call the dealership tomorrow and see what they say about it.

I didnt get to see it. The guy went in to his PC and pulled up catalytic converter and gave me a price. After reading around a little I seen that there is an ECM update that may help solve the problem. I will call the dealership tomorrow and see what they say about it.

I am going thru the same thing right now with my 02 Altima. Same error code P0420 and my car has all the current ECM updates and recalls taken care off. But this year alone, the headgasket, radiator and now the catalytic converter needs replaced.

I'm getting mine fixed on next Tuesday.. This car has never had any problems untill it was 5 yrs old back in April. I bought this car brand new back in 02 and never a problem until now.