i have a 2000 with 85,000 miles on it. the car idles great, hits vtec without any problems and will beat any other stock S2K. The car seems to misfire/backfire/hesitate when i try to accelerate in any gear under 3k rpm. if im under 3k rpms and give just a little bit of gas i have no problem. its almost like i have two VTEC's one at 3k and the other at 6200. i can't tell if it's a misfire/backfire etc. but it basically runs like S%$T under 3k. i have cleaned the TB, swapped out Map sensors, clean the IAC, looked for vaccume leaks, reset the ECU and changed the spark plugs. I have even ran a few tanks of 100 octane to see if that would clean anything out. i bought the car with 68,000 miles on it and had absolutly no problems with the car untill recently. the problem hasn't gotten any better or worst in the last 1k miles. but i the last 2 weeks the car also seems to backfire around 8k for the first 5 or so red line shifts. after that the car runs fine in the high rpms. i have always made sure i had three bars before going to the red line. im kind of stumped right now. i have some mechanical knowledge and i really can't afford to take it to honda were it will cost me 100 bucks just for them to look at the car. any help would be greatly apprecitated.

 

I forgot to mention that no CEL or MIL has come on.

 

maybe you need to clean or replace your injectors.

do you have any modifications?

 

Injectors...don't bother cleaning, the problem will be back in a less than 10k miles. Just get new ones.

 

i have an intake thats all. so after i get the injectors off how would i clean them. if my injectors were bad why would the car still run great after 3k rpms? the car even idles normal, never stalls or boggs down at a stop light. But taking the injectors out and cleaning them won't cost me anything so i wont hurt. i'll do that tommorrow after work.

 

Reseat the connection to the MAP sensor on the top of the throttle body.

 

i have played with the map sensor and all the connections for everything on the motor. i even swapped out my map sensor with my buddies. the map sensor made no difference and he even still has my map sensor on his car.

 

Another vote for the injectors.

 

You have an injector cleaning kit and assorted o-rings in case you damage one taking the injector apart and new internal injector filters? Just cleaning the tip won't do anything.

Many of us have had the injector trouble you are mentioning. Personally, I don't believe it is a cleaning issue, although cleaning can temporarily help. I think it's an issue with either the internal coil or magnet on our injectors.

 

make sure you have orings. I cut or mashed quite a few putting my fuel rail back on once. The metal there is raw and sharp.