My Maxima has a check engine light illuminated. It has been reset over the past 2 years but retturns. Normally, the cars runs fine but once last fall and once this fall in extremely humid conditions and the temperature around 50 degrees (F), the idle got extremely rough. Both times the rough idle disappeared. Last year the idle returned to normal after several miles but this time I drove home around 14 miles including expressway driving without the idle returning to normal. After restarting the car the following morning, the idle was fine but the indicator is still on. I can not remember last years code number but I believe it identified a fault with the catalitic converter. My neighbor, who was my mechanic at the time told me to replace the gas cap, but the fault returned after several weeks. Could a sensor be causing the problem? If so, where is it located and how difficult is the sensor to replace? The car has 36K miles and is only driven around 4K miles per year. Thanks for your help. Bill
That CEL (check engine light) is just a kid in class waving her hand trying to get you attention because she has the answer. You need to have the codes read. Some places will read them for FREE. Try Autozone or Advanced Auto Parts. Get the exact code (like P0123) not just their translation into English and post it back here.
Just be cause it seems to drive OK does not mean there is not a problem and that problem could be something very serious and could get a lot more expensive if you ignore it.
Sensors report problems. Sometimes, they are the problem; but, how you know? Get the code read. It’s free , even, at Auto Zone, etc.
I finally had the opportunity to have the codes read. Four codes were noted, of which, one occurred three times and the other once. The codes were: P1320 (3 times) and P0420 (once). After being read, the codes were reset but immediatly returned. The car only runs rough in higher humidity and when the outside temperture is approximately 50 degrees. The days that the codes were read, the car was running rough.
There are Nissan Service Bulletins for both trouble codes. P0420 is “catalyst system efficiency below threshold”. It’s covered by NTB00-070a, dated 09/06/2001. The fix is to reprogram the engine computer (NOT replacing the catalyst). P1320 is “distributor signal interrupt”. It’s covered by NTB01-059, dated 09/06/2001. The fix is to check and repair (if damaged) a wiring harness, or, replace the ignition coil(s).
You can get these Service Bulletins from the Internet, or alldata.com, the Nissan dealer.
You can check other garages, but, the Nissan dealer may be the only one who can reprogram the computer for the P0420 code.