The last few days I have been experiencing a problem when I am in vtec. What happens is that as soon as I hit 6K rpms the engine seems to stutter and then catches after a second or two. From 6500 to 8000 it usually feels fine and then from 8000 to redline the same stutter happens. It kinda feels like something is wrong with the exhaust flow. It's like vtec is being switched on and off. I know that it's not the oil pressure because I have checked that on 3 occasions since this started and the oil level is fine.

Something else began about two weeks ago also. When I drive for more than about half hour and then get out of the car I smell a somewhat burnt odor. It seems to be coming from the underside of the car, near the rear wheels. I had the car put on a lift and could not find anything wrong. Anyone have any idea what this may be? Can these two issues be related? Bad catalytic converter maybe?

 

Do a search on MAP sensor.. it sounds like that may be your stutter problem.

 

I did find this. It kinda sounds like what I'm experiencing. For some reason I'm starting to think that my cat may be bad. I have a feeling that it's not my map sensor. Any other opinions?

"I wanted to revive this thread to document another CEL caused by a melted cat that also melted the secondary 02 sensor.

The initial indication that I had a problem was the Check Engine Light(CEL). The other problem that most people haven't documented was a definite performance problem while VTECing. The acceleration would stutter as if the exhaust flow was being restricted or if VTEC was being engaged and disengaged.

The dealer here in Houston, David McDavid, overnighted a new cat (TWICE) They made up for it by compensating me with a rental car for the trouble. On day 2, they had everything fixed and the car is running much better again.

The emmisions warranty is 80k and will cover the catalytic converter replacement which is approx $950. The basic or extended warranty will cover the burned out 02 sensor ($180)."

 

Nope.. no CEL and high throttle stumble is more likely the MAP:
https://www.s2ki.com/forums/showthread.php?...t=MAP%20problem

 

[QUOTE]Originally posted by getchastuff
[B]I did find this.

 

I'm reviving this post because I also have a stutter when in vtec.....I'm not too sure what it is....whenever I get past 6000rpm there are very subtle pops just like fuel is not getting combusted or vtec is going in and out......

 

So did you tap your MAP sensor? For me, that corrects the problem temporarily.

 

I tapped the sensor and the car idled better but the stutter was still there.....