Problem With Rb20det, Not Holding Revs/jerking Forward & Back

[Dean_HR31]

Hey guys..

Im trying to work out what is going on with the engine... whether its an air leak or a sensor or whatever..? Below are the things the car is doing.

1.) Car idles fine, but when trying to hold revs in nuteral (3500k for example) the revs drop 3/4 way back and then climb up again, then drop, then climb back up again repetetively while im holding the accelerator down a certain amount

2.) Because of the above, the car obviously jerks forward and back a fair bit when driving which is DAM annoying!! eg cruising along in 4th gear at 70kms, the car will back off & accelerate again repetitively while im holding the throttle a certain amount

3.) In general, it is missing about 60% of the power its supposed to have... something is obviously holding it back ALOT. It feels like a combination of an air leak/and or faulty sensor??

I might also ask, is there an easy/effective way of checking for air leaks?? Ive tried to find something visually but had no luck...

Edited September 1, 2010 by Dean_HR31

[tridentt150v]

Also think about your fuel system - pump, filter and regulator. Get a fuel pressure test done, 10 minute job.

[DVS JEZ]

have u changed anything lately?

is it stock ecu?

[Dean_HR31]

Hmmm how much is a fuel pressure test to get done?? How is it done??

And, no nothing has been changed. The car is stock as a rock besides an air filter.

Could any of the sensors be playing around? If so which one most likely?