My Rb25det Stagea Engine Is Having Problems Starting

[lukew105]

Hey guys got a staggy series 2 engine in the 32 gts4 at the moment. Was running pretty well with gt2871 turbo s15 injectors q45 afm and remapped ecu... took these all out and put it back to standard and now its having massive problems starting.

Car currently has:

Front feed plenum with larger throttle body

Rb25 neo afm

Series 1 afm (engine is series 2 but people have told me it doesnt matter)

Series 2 coil packs

stock rb25 injectors

Stock turbo

These are the onyl things that have been replaced

Its struggling to start.. have got it started a couple of times but runs like dog shit.

Plugged a power fc in .. still ran like shit and struggled to start.. obviously tuned differently but ..

Have injector pulse.. have spark..

Plugs foul up very quickly.. cleaned them numerous times..

Pull the cas out and spin it and injectors click.. not completely fluently but still click...

So given that.. im really not sure where to go from here

Any ideas would be much appreciated

[paulr33]

if the stock ecu has been remapped to suit s15 injectors and q45

and you put the stock parts back in, it will run like a bucket of crap

likewise with the powerfc - i would expect same results

overfuelling, mega rich and just a boggy tune

my advice would be to put the PFC in and DATA INIT to factory defaults

then it should start first stop providing you have factory afm and injectors

[dmac_25]

if the stock ecu has been remapped to suit s15 injectors and q45

and you put the stock parts back in, it will run like a bucket of crap

likewise with the powerfc - i would expect same results

overfuelling, mega rich and just a boggy tune

my advice would be to put the PFC in and DATA INIT to factory defaults

then it should start first stop providing you have factory afm and injectors

or get yourself a standard s2 r33 ecu for 150 or so

[10MinuteCar]

well the best way is to list all the possible alternatives, then to cancel them out 1 by 1 effectively till you find out what it is. Now could it be theres not enough petrol?

[lukew105]

Yeah heaps of fuel in the tank

Been told series 1 ecu should work but im having my doubts

an rb20det ecu was remapped.. but that has been removed and replaced by a stock series 1 ecu no remap

[dmac_25]

Yeah heaps of fuel in the tank

Been told series 1 ecu should work but im having my doubts

an rb20det ecu was remapped.. but that has been removed and replaced by a stock series 1 ecu no remap

S1 no go with the coils you have

[lukew105]

so how does it work with a remapped 20 ecu?

[Duncan]

so....don't worry about starting the car - did you keep the gts4 sump, or did you swap the rear diff? because the stagea diff ratio is different to the gts4 diff ratio

[lukew105]

kept the 20 gts4 sump.. these things arent the problem because the car ran well previously!

[blind_elk]

so how does it work with a remapped 20 ecu?

They aren't S2 coils? Or it isn't a RB20 ECU.

[lukew105]

Yes it was a remapped rb20 ecu by jeff at speed labs, and yes they are series 2 coil packs

[blind_elk]

Hang on - you've listed 2 AFMs in your original post.

Try unplugging whichever one it is.

[lukew105]

Sorry was meant to read ECU

[blind_elk]

What was supposed to read ECU? NEO, or Series 1?

[lukew105]

The ecu is an RB25det series 1 ecu

The afm is an RB25det out of a neo engine

[johnbarry88]

vacumm leak or leaking injector o ring