Rb 25 Idle Problem

[blu hsv]

Hey i am having some trouble with my rb 25 i put into my vl .

once the car is up to operating temp when i rev the car over 2500-3000 rpm and back off realy quick the car stalls. also have to put my foot on the throtle to start it.

i have tryed cleaning the AFM , AAC vavle, changed the plugs, checked timing and checked for vac leaks still no change.

any help would be good

[RRob]

From my past experiences it sounds like there is 2 wiring issues.

First one would be lack of power supply to a common power wire(IAC VCT O2). Blue wire/ white trace. Meant to be connected to a purple wire? under dash of vl that powers up at same time as FPump.

Second would be no start signal going into pin 43 of the ECU. Grey wire/ red trace maybe. + trigger on crank.

[blu hsv]

Thanks for the comment.

When i wired it up i hooked up 2 power wires black/ red trace and the white/ black trace

what does putting power to pin 43 on start do?

Not sure of the blue wire/ white trace. do you know the pin number for that?

[RRob]

Pin 43 tells the stock ECU the car is trying to start and adjusts bits and pieces accordingly to help the process.

Blue wire with white trace doesnt go to the ecu. Its in the white/black connector 30cm away from the ECU.

[blu hsv]

cheers mate will look for that you dont know what number on the plug it is? and that needs to have power from the fuel pump relay?

[The Mafia]

do you have a atmo BOV?

[blu hsv]

Car has no stock or after market bov

[PM-R33]

That could cause it.

If you are running the stock ECU it is designed to run with the AFM and factory BOV. On a quick rev the factory ECU and AFM are designed to compensate for the air getting plumbed back into the intake and adjusts the fuel map accordingly. This can cause a stall. With you running no BOV obviously this has the same effect as running an atmo bov from the ECU's point of view.

It's been a while since I looked up exactly how the stock ECU and AFM run with the factory BOV but I believe I got that right. The Mafia can correct me.

[blu hsv]

The car i got the engine out of didnt have and factory or after market bov. engine has a front facing plenum. it didnt have the problem when it was in the 33 so it could be a wiring problem?

[karma_syke]

coilpacks?