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well i got my rb25det r31 and it free revs well.

But once you put load on it driving it starts to rev and then breaks down and wont rev, and starts backfiring as if it was a limiter noise...

when you change gears the bov makes a high pitched whistle instead of the normal rb25det bov noise, but thats in 1st and 2nd but from 2nd to 3rd and 3rd to 4th and 4th to 5th it makes the normal noises...

and when you do the limiter revving under load noise when you put the clutch in the revs drop down then it revs back up

free revs all the way out but wont rev under load

what could it be?

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coil packs or spark plugs. there are a few different fixes for the misfiring problem.

#1 - gap your spark plugs to .8mm (do that if not already done)

#2 - fix your coil packs, there are a few threads around on how to do this.

as for the bov sound, im not too sure if this fits the sound you described but it might be turbo chatter, where your bov doesnt actually open, the noise you're hearing is the air passing back onto the turbo blades.

Hey you are reading my mind but about four months earlier, If you have played with intercooler and a boost controller on the car you would have noticed that a nipple would be missing on the inlet part of the pipe before the bov that is the vacuum pipe that opens the actuator on the internal waste gate and if you dont have that hooked up you will hit max load causing seveire breakdown at 2k trust me i had the exact problem!!! easy way to fix it is to simply put a T valve in on the blow off valve hose that goes to near the back of the plenum!! that will get rid of your break down at 2k.. P.M if ya want a photo!

made a slight difference but still breaks down, but you can get past the banging and then it tries to pull.. could it be a fuel problem?

but what concerns me is, i gave it a boot full and then went to go into my driveway, stopped and the car stalled, then i started it again and it stalled again but started it and gave it a rev and it idled fine...

its quite farken easy u see...

u get a gapping tool, pick the gap u want, get ur spark plug out, tap them on the ground softly until the gapping ruler u are using fits between the sparking element and the underside of the tip. ur spark plugs come pregapped at 1.1 thats not enough for boost past 6-7psi. that will work, if ur unsure how to do it, go to ur mechanic.

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