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

Dean_HR31

By Dean_HR31,
in Engines & Forced Induction

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Dean_HR31

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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 by Dean_HR31
Dean_HR31 Mentor

Dean_HR31

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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?

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