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Just looking for ideas, my car is not making the power it should be and hesitates at higher rpm when full boost hits. I have a hi flow turbo and thought this could be causing a boost cut but its only hitting 13psi max and was doing it with the std turbo at 10psi as well. The afm meter has been replaced and spark plugs changed.

im thinking that it could be a knackered fuel pump or maybe a coil pack?? any help would be appreciated

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https://www.sau.com.au/forums/topic/19117-rb20det-breaking-down-at-rpm/
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Similar problem to what im having at the moment. Ive also changed plugs, fuel filter, put a front mount on, and today i tested another computer, and setup an oil pressure guage to measure my fuel pressure and was also fine. The only things it points to now are one of the sensors is faulty, read this thread and do the diagnostics and see how it comes back, im guessing its a crank angle or knock sensor playing games :)

http://www.skylinesaustralia.com/forums/sh...&threadid=19018

Let me know how it goes, im doing mine tomorrow night :)

cant find that link dude?

did the fuel filter today, getting a new fuel pump soon but have to put that on hold because the car has started making the same sound it did when the old turbo was dying :) (a high pitched scream/squeel) im hoping its a gasket, only one left is manifold to head, changing it tomorrow fingers crossed. had nothing but bad luck thus far

let me know how you go with that cheers

That link is there, but it was under the topic Auto RB20 ecu on a manual or something like that by me. I did the diagnostics and it came back with a faulty knock sensor which would make sense why my performance on my car is poor. Have you found that after 5500rpm it looses a noticable bit of power?

The hesitation at high rpm is probably due to an over rich mixture and this seems to be a common problem with these engines. We found that at around 10-12psi mixture strengths of 10:1 are not uncommon and this causes the engine to flutter at high rpm and causes a noticable decrease in power, ideal A/F should be about 11.8:1 to 12:1. Re gap your plugs to .75mm,we have found that NGK BCPR6Es11 plugs to be about the best.It probably wont be a coil as this is generally indicated by a droped cylinder at idle speed not a high rpm miss.

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