heresnowhy

Long story short, got car back after two months in the body shop, bastards didn't bolt the differential mounts and numerous other items back in to the subframe so it was a little weird handling and shifting, resulting in a mishift. Yeah the dreaded over rev. New head installed, car runs like a champ except , vtec audibly activates (invidia v3) but just plain doesn't go anywhere and starts getting slower as it approaches 8000rpm where it plains runs outta air and starts choking. If I rev much passed 8k it sounds similar to a misfire but does not throw a code. Ran next to a stock s2k and like i suspected, at vtec time, my car is out to lunch, though I can actually here it switching into vtec through the exhaust note. My only idea is maybe a cylinder or two isn't switching? Anyone ever run into this problem?

mxt_77

First/easiest thing to try: Unplug the MAP sensor and plug it back in securely. Except for the misfire sounds at high RPM, that sounds like the symptoms I experienced w/ my MAP issues. Basically, it felt like somebody threw out an anchor over 6 or 7K RPMs.

heresnowhy

I should have added more information in the first post. Here is a list of what I have done already. 1. replaced map sensor. 2. replaced spark plugs. 3. removed and inspected vtec solenoid screen and performed opcheck in accordance with helms. 4. performed a valve lash adjustment for the umpteenth time. 5. checked for vacuum leaks. 6. checked and rechecked timing. 7. i'm stumped for now...... And all of this a day before I moved across the country, drove her 1200 miles straight without any problems other than stated above vtec issue.

jyeung528

let us know when you find out what the problem is.

RACER

Have you checked the oil level

heresnowhy

Yes, all of the obvious things have been done. Oil changed, new filter, changed oil again, new filter again....

negcamber

Ryan...did you get the screen on the VTEC solenoid back on?

OH...and he's also replaced the cat.

heresnowhy

Hey Neg, yeah the screen is back on. I'm running out of ideas....

mxt_77

Do you (or someone you know) have a datalogger? Maybe see if you can do some datalogging to see if you're running rich, or if the timing is retarded for some reason, etc, etc. Or what if the throttle position sensor is not right?

I'm assuming that during your valve lash adjustment you verified that the cams were installed properly (i.e., not off a tooth on the chain). What about the cam position sensors? Didn't turbo_pwr have issues w/ his car when the cam position sensor was damaged or installed improperly? I can't remember if he got a code or not, though.

What about airway restriction? The tech didn't leave a rag installed in your intake tract or throttle body while working on the car, did he?

negcamber

Well...the tech working on the car was Heresnowhy himself.

But it does feel like the car is running out of breath. No intake obstruction...has a J's intake with clean filter. Thought it might be an exhaust restriction...but replaced the cat and has a new exhuast from the cat back. Still stumbles at high rpm.