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i have had nothin but problems with my rb25 the last 2 weeks since i put it in. i have fixed all the hunting and running like shit on boost issues with a new afm. it still wont revv at all untill wared up, but i have been told thats just what the cold start islike on some of these 25s. anyway once its warmed up it wont revv at idle is misses and struggles then once its into boost or above about 3 grand it runs fine, drives well, only running 10 pound atm but no problems except the initial down low!

to fix the problem you can completely clamp of the return fuel line. BUT i have a big fuel pump which i just replaced, its got fuel pressure, new fuel reg, all fuel lines are fine, new coil packs spark plugs everything lol! i dont think its fuel just somehow heaaps of fuel pressure fixes the problem. the thing is i dont really remember this prob before i replaced afm, you reckon it could be another faulty one?

only other ideas is that its my comp or blocked injectors. does anyone know if an afm could cause these symtoms?

Edited by r32drifter1
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its a direct import iv never touched any of that stuff, its more like a running out of fuel untill it hits revvs, tried playin around with the timing a bit. only made it worse. someone has just put it to me about an air reg might not be getting 12 volts cause it doesnt run off computer power?

to fix the problem you can completely clamp of the return fuel line.
Usual sign of a dud FPR. Have you put a fuel pressure gauge on there?

Have you replaced the fuel filter? Did you get the injectors cleaned before installing the engine?

could it also be that gold valve that hangs off of the plenum closest to the firewall? cant remember the proper name. but i read that when people blip the throttle, and they have hunting issues for idle, it can be because this valve is blocked a bit.

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