I have a 93 Altima with an auto tranny. I have black smoke coming from the exhaust and the plugs are fouled. I fugure it is running rich. Also the car idles erratically. Could this be the coolant temp sensor making it run rich or possibly an o2 sensor? Any ideas would be great. Thanks.

Also it is using gas like a mother. I drove about 30 something miles and it used over half a tank.
Modified by theboz at 10:12 PM 3/16/2006

had this same problem in my 96 GXE and it was the MAF

Same problem here?

Definitely check the CTS, MAF, 02, ignition timing, and fuel pressure & FPR.

I had the same kinda thing and it was the O2 sensor. but why don't u get it scanned and see codes u have? that's a lot better then throwing parts at it. in my case i didn't have a check engine light but when i monitored the 02 it would sometimes not switch from lean/rich the right number of times. but seriously see if u have any codes.