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Rb25det Problems..

sidewayssam
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sidewayssam Mentor

sidewayssam

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hey just a quick question, a mate of mines has a r33 with aftermarket turbo, intercooler, exhaust, computer, 800hp fuel pump and lately its started to run rough, he had to put 95octane fuel in it the other day and thats when the probs started, weve changed the fuel filter and plugs but still when it stars to boost it starts sttuering like its havin fuel surge and backfiring, has any one else had similar problem? what should we check next? injectors or coils??? cheers

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Garret_Volden Enthusiast

Garret_Volden

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Posted
hey just a quick question, a mate of mines has a r33 with aftermarket turbo, intercooler, exhaust, computer, 800hp fuel pump and lately its started to run rough, he had to put 95octane fuel in it the other day and thats when the probs started, weve changed the fuel filter and plugs but still when it stars to boost it starts sttuering like its havin fuel surge and backfiring, has any one else had similar problem? what should we check next? injectors or coils??? cheers

thats exactly what my car is doing right now

it did it when i had my old 2 litre in it and i swapped in a neo and it still does it

the only things that are the same are the fuel pump,which i changed,the boost controller which i am changing tomorrow,and the maf.

so my guess is that the boost controller or the afm is not working properly,because it only happens under boost.

so try checking the boost controller and the maf

i will update if this thread when i figure the problem out,but i am fairly certain it is my old shitty manual boost controller sticking.

cheers!

sidewayssam Mentor

sidewayssam

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yeh its got aftermarket ecu and recently had full tune by imports101, could it be a problem with the stock injectors? its my mates car, me and him both had to fill his skyline up and my ss up with 95octane wich our cars dont run too good on, after that i had similar probs with the ss but i changed the plugs and and me valkve springs at the same time n it came all good but the skyline just gettin worse

TTT Grand Master

TTT

Posted
Posted

when you changed the plugs in the skyline, what plugs did you use?

and what gap?

May be a stupid question but have you got rid of the 95 fuel yet?

if not, maybe buy a bottle of good octane booster and dump that in the tank with the 95.. it should bring it's rating back up to 98 or so.

sidewayssam Mentor

sidewayssam

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we didnt check the gap we just got some new ngk ones from repco and just assumed the gap would be fine, yeh we drained the fuel and ran injector clean through the engine and now are runnin it on 98octane ith octane booster,

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