RB25DET hesitating at 4K RPM.

[leesredgt]

Ok, ive swapped a RB into my 240sx hatch about a year ago and i got it runnign but it wants to hesitate when it hits boost around 3K rpm almost liek theres a vaccum leak.Ive cheaked the MAF its good.Ive checked for boost leaks i cleaned all them up still got the problem.Set the timing to 15* like the manuel says still nuttin.Changed spark plugs to NGK'S still nuttin.So my question is could it be a bad ECU causeing this? How can i tell if my ECU is throwing any codes? My light isnt lite or anything?

[4x4le]

what is the gap and heat rating on the plugs?

[leesredgt]

The gap is .o8 i belive and i cant rember the heat range but i know there correct.It dosent really feel like its blowing spark out its alomost like once you 3-4k its like your start towing somthign the car just slowes down and then picks back up.It right when boost hits so its killing my top end power.

[gotspins13]

check your coil pack and see if eveything is getting good connection, my friend had the same problem

[sillyvia13]

rewire your mafs.
inside needs to be rewired, my buddies r32 gts t 4 or what ever the fuck its called...
Had same issue... I guess inside the solder connections are real small and chinsy...
try that up...
he got info from a skyline forum...
he's on here too.. sileighysek.. pm me if you want me to connect you two! GL AND PEACE

[leesredgt]

sillyvia13 (http://zilvia.net/f/members/sillyvia13.html) -are you talking about rewiring the MAF itself or the wires runnign to the MAF?

Is there any way to test your coil packs?How about cleaning the spring?

[RBPowerSilvia]

Ok, ive swapped a RB into my 240sx hatch about a year ago and i got it runnign but it wants to hesitate when it hits boost around 3K rpm almost liek theres a vaccum leak.Ive cheaked the MAF its good.Ive checked for boost leaks i cleaned all them up still got the problem.Set the timing to 15* like the manuel says still nuttin.Changed spark plugs to NGK'S still nuttin.So my question is could it be a bad ECU causeing this? How can i tell if my ECU is throwing any codes? My light isnt lite or anything?

Get a DMM and measure the ohms on each coil pack.... im pretty sure the specs are between .07 ohms and .11 ohms... let me know if that works, good luck---- oh and if they are bad and that is your problem do this>>>> go to aut store and buy 87' 88' buick grande national coil pack. should be like 40 bucks, then buys whatever spark plug wires u want.. then all you have to do is wire the coil pack into your ignition rectifier and your set....