My Rb20det Problem

[hectic32]

hey all have a rb20det in my r32 gtst following mods

fmic

plazmaman plenum

bosch 040 intank

450cc power flow injectors with gtr resister pack

r33 turbs @ 14psi

power fc with hand controller

boost controller

now my problem is at idle it has a slight miss like a popping noise from the zaust and say i rev it to a certian revs and hold it there it does the same thing but if i turn the a/c on it runs smooth as

i have tried the following things off a friends car such as

cas

ignition module

coil packs and loom

tps

and have jus put new plugs in but isn't any different and they are gapped to 0.8 ngk v power plugs

now with the tps on the power fc it dosen't show a reading like its 0.00 all the time and now and then it will have a slight flick of power like 0.03 or sumthin random like that and my engine light is on all the time and on the power fc the tps voltage reading is highlighted but i did try the tps off my friends car and it done the same thing also have checked for air leaks and stuff like that aswell and is all good

so would the tps cause the slight missfire that im having cos it the only thing i can think of

have already search in the search button heaps but there is no answer to my problem

your help would be great thanks

Edited March 8, 2009 by hectic32

[ashr32]

hey all have a rb20det in my r32 gtst following mods

fmic

plazmaman plenum

bosch 040 intank

450cc power flow injectors with gtr resister pack

r33 turbs @ 14psi

power fc with hand controller

boost controller

now my problem is at idle it has a slight miss like a popping noise from the zaust and say i rev it to a certian revs and hold it there it does the same thing but if i turn the a/c on it runs smooth as

i have tried the following things off a friends car such as

cas

ignition module

coil packs and loom

tps

and have jus put new plugs in but isn't any different and they are gapped to 0.8 ngk v power plugs

now with the tps on the power fc it dosen't show a reading like its 0.00 all the time and now and then it will have a slight flick of power like 0.03 or sumthin random like that and my engine light is on all the time and on the power fc the tps voltage reading is highlighted but i did try the tps off my friends car and it done the same thing also have checked for air leaks and stuff like that aswell and is all good

so would the tps cause the slight missfire that im having cos it the only thing i can think of

have already search in the search button heaps but there is no answer to my problem

your help would be great thanks

very strange mate, i have the same mods but have gtr injectors and a much worse miss fire which im working on fixing at the moment. when i get the car back together ill get the data from the PFC and post it. it might help.

so when did you get the miss? after the injectors? whats it like with the stock ecu? does its start?. mine didnt so i can only test with PFC. i know the valve under the throttle body works when the ac is on maybe thats a good place to start?

let me know how you go and get the info back to me. maybe we can fix each others issues. where are you located?

good luck

ash

[hectic32]

yeah well i first put the injectors in and it was obviosly runnin rich but drove to the tuner got it fully tuned and it was all sweet made 258hp atw and the tune was all good anyway after that it had a slight miss and my tuner jus said that it was probly jus fouled plugs so i replaced them and that same day the engine light came on aswell also the other nite i went for a drive once at operating temp and i turn the car off it wouldnt start at all til i waited it to cool down a bit

[hectic32]

also located 45min from the sunny coast queensland also cant put the standard ecu in cos runnin the resister pack now also only can thik it the tps is yours workin fine let ys know how you go anyway

[Ruffels]

i have an rb20det in my S12 Gazelle... and i had the same issue after installing my front facing plenum... turns out i hadn't taken enough care when extending the wiring for the tps (as the tps sits in a much different position to standard) and the shielding wire around one of my tps wires was actually touching the internal conductor of that wire where i had cut it to extend it!

perhalps check that out, especially because your power fc has highlighted the tps

[hectic32]

yeah thats what i was sorta leaning towards sumthin to do with the tps wiring cos had to do the same thing and i jus recently rewired it so might double check that for starters

[hectic32]

rito had a look at my tps wiring and one of the wires from the plug joins into the coolent temp sensor thats was sumtin that i haven't checked could this be a cause of the slight miss fire at idle cos the thing is when i very first start it it runs fine but then not long after that it will have the problem and also once i take it for a drive and gets to normal temps and i turn it off again it has trouble starting?

any ideas people?

[hectic32]

anyone?

[hectic32]

ok people have now solved the tps problem and my engine light is off but still got the miss fire any ideas?

[hectic32]

still have the miss at idle once i take the car for a good drive and it idles after that the miss is worse could injectors be causing this problem? any other ideas would be a great help thanks

[zeko33]

dude..... try gap ur spark plugs closer.... even if you go into a store and say i need spark plugs for rb20det they still aren't gapped close enough..... i had the same problem and all i did is gap them closer... since then no worries.... theres a topic on here that tells you the measurements...... also turn you boost down as 14psi will destroy the turbo... they are not that strong...... keep it about 11-12psi to be safe...

catch hope it works for ya

[DuFFR32]

I have similar mods on my 32, Not sure about the miss on idle.... what heat range plugs are you running? try a z32afm. I had bad missfire on boost so I bought new plugs gapped them to 0.08 and cleaned every part of the coil packs and now it never misses a beat on 14psi.

maybe one of ur injectors is a lil dirty? run some octane boost n clean through it and see what happens

Im sure 14 psi is a bit too much for a stock 33 turbo id go 12 max

cheers