The story. 3 weeks ago I had my warpspeed y pipe put on. Its basically the same as the cattman but flows a little better, and was much much better quality...but thats OT.

So as I pull out of the muffler shop, my car hesitates BAD. But it only throws a fit for about 5 seconds and then was fine. I chalked it up to the "newness" of the pipe burning off and giving the o2 some funny codes. I did notice that as I evaluated the power of the new pipe I lost a decent amount before 2K rpms, but then it kinda picked up after that to normal.

One time fluke? NOPE. Almost everytime I'd start the car, warm or ice cold, my car would have this hissy fit. It would be fine in park at idle, but then in Drive, when you stepped on the gas, it would hesitate, and stumble. But only do it for 5 seconds are so and then it never did it the rest of the ride.

I suspected that the shop damaged the o2 sensor so I ordered a new Bosch one. Got it from foriegncarparts.com???? something like that. 54 bucks plus shipping. The dealer only charged me 13bucks to put it in.

Sucess! That one time a drive hesitation is GONE. And the car has more power below 2000 rpm.

Other notes:
The gas mileage is not better with the new o2, but even with the busted o2 I was getting nearly 30mpg with all highway driving. I did 1000 miles with old 02 and 1000 with the new one and no difference....but again, was is great with either.

I know my OBDI maxima is not as modern as the VQ's so I would expect the MIL not to come on for a misfire, but I wonder why it doesn't come on if the o2 is acting up? I do know my MIL light works(It comes on when you first start the car with all the other warning lights).

Mike S.
93Maxima....100,000 miles!