jyeung528

isn't this an oxymoron?

if it runs fine UP to a certain rpm...but not fine beyond that rpm...then no, i wouldn't agree that your engine is fine. it might not be the valves...but I highly suggest you do a compression and leakdown test, in addition to checking the vtec solenoid, plugs, and injectors.

xman03

I replaced the plugs and compression turned out fine at 220/215/215/220. After all it turned out to be a faulty fuel pulsation damper.

negcamber

Interesting...never heard of that causing the symptoms you mentioned. I'm curious...who discovered that or how/why did they think that was the problem. If that fixed it, that's some good diagnosing there.

xman03

Yep, I took the car to JE Import Performance. It was a PITA since the car was not throwing any codes, compression was fine, so was oil pressure. Pulsation dampers rarely go bad but unsteady inflow of fuel seemed to break it up in the higher rpm right around vtec engagement point. The mechanic there was able to figure out the problem and replace the damper on the second day the car was in the shop.

jyeung528

what does a fuel pulsation damper do?

xman03

It dampens the fuel flow so it is more consistent due to the injectors creating a lot of pulsation in the fuel rail.