HELP: drives fine for 15 min, then wont rev up or idle nicely

MAF. My '90 Sentra had the exact same problem last winter (minus the glowing convertor). Since it was so cold out at that time (0*F), I thought it was a problem with the fuel gelling from the cold. I started toward work one day and it ran fine for a few minutes and then it started acting like it was out of gas. I stopped and it ran just fine. Then, when I would try to accelerate, it would chug really bad and not accelerate much over 15mph. Finally, I babied it back home and I got the car inside the garage. I let it sit for a while and it would idle fine when it was first started, then when I tried to rev the motor, it would rev a little and then act like it was starving for fuel.

Well, come to find out it wasn't starving but rather running SUPER rich. I replaced the MAF and then the sparkplugs since they were all soot-covered from the f'ed up A/F mixture. Its run fine ever since...except that all the soot and crap plugged the convertor up and I had to replace it.

In fact, thats why I'd almost bet a paycheck that your problem is the same. Its running like my car was and your convertor was toast from the way the engine is running.

Mine did the same thing. The first day that it did it, I thought it was frozen lines. It ran like crap and I tried starting it up after an hour or so and it ran like crap. Then, I let it sit over night and it fired right up. Then, thats when it started to really run bad and I pulled it in the garage after driving home at 15mph.

BTW, the MAFs are pretty expesive. I saved a load of money by ordering from this guy at Quality Nissan instead of buying from my local dealer.

Greg Vogel 800.229.2292 toll free. Tell him you got his name from Nissanforums.com and see what price he can get you compared to the dealer.

Good luck!