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

[Liquidshadow22]

Hey,

Please don't sizzle me for not posting about the mustang. I'm working on my mom's 95 nissan quest and its driving me nuts.

I noticed after 10 min of driving it wouldn't rev up and sounded like the engine was choking and would eventually die. I'd give it gas and it would barely get to 3k.

The first 10 min it drove fine.

Well the first time it happened, I noticed the pipe near the cat was glowing red so I replaced the rear cat and gutted the busted front pre cat.

The problem is still there nevertheless however the glowing is fixed and the exhaust is clean as a whistle.

I don't want to keep asking my mom to buy more parts till I'm sure.

Vacuum line? Modulator under the distributor? Bad Fuel Pump?

These are some ideas. ANY help would be appreciated.

Thanks in advance.

Jason

 

[nickthegenius]

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.

 

[Liquidshadow22]

thanks ill have to give that a try.

The other thing is, the van has to sit a long time before it runs ok for that 15 min. If I start it up like 2 hours later it will still run crappy.

J

 

[nickthegenius]

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!