rb25det problems

[89"rb240]

i swapped a rb25det into my 89 240 and it runs great...idles fine starts fine...but when i go to drive it at about 2500 rpm it starts hopin and i have to shift and it does it at about the same rpm in the next gear and it will not build boost at all...all help would be very much appreciated thanks

[Yellow4g63]

Might want to check for a boost leak or check your maf.

[89"rb240]

its not my maf its as if its fuel cutting as soon as i start to build boost

[Joe]

[quote="89"rb240"]its not my maf its as if its fuel cutting as soon as i start to build boost[/quote]check for boost leaks, check your maf.

[Beanstalk]

[quote="89"rb240"]its not my maf its as if its fuel cutting as soon as i start to build boost[/quote]It would have to be a BAD boost leak to do this..... My money is on fuel.... unless it does the same thing just revving the engine? Some jdm engines come upgraded with chipped ecu, wrong mafs and bad sensors. Process of elimination and if I can tell you the best advice I've got from the guys here .... Check your GROUNDS!!!! lifesaver

[89"rb240]

yeah it does it when im reving too wats that mean?

[240z4u]

Something is wrong with your MAF circuit. Do some searching, it is pretty common.

[ka24eracer]

Thats how a rb25det act when you unplug the maf