Injectors Constant Power

[SiR_RB]

Since i got my new GTR I noticed with ignition off, the injectors were making a buzzing sound and showing 6-8v, today we spent all day trying to find the issue, what we came up with so far:

Disconnect ecu and injectors still have power

Disconnect ECC relays behind ecu, injectors still showing power

Disconnect each relay in engine bay one at a time, no luck

Battery is in the boot and has an isolation switch in the engine bay. If we turn that off they dont get power and everything is good (as expected)

Has anyone experienced this before ? Is there anything else I can check ?

[XGTRX]

So is it the constant or switching power that's live?

[SiR_RB]

Actualy think it was showing 12-13v so would assume constant ?

[SiR_RB]

The only way we could stop voltage going to them was by turning the isolating switch off / disconnecting the battery terminal

[hardsteppa]

What ecu? The 2ndhand wolf ecu i picked up seems to do the same thing.

[SiR_RB]

Car came with a vipec v88

[89CAL]

How did you test voltage?

Injectors always have power, they are earthed through the ECU

[hardsteppa]

Yeah but with ign off, injectots should have no power.

[KiwiRS4T]

Someone may have directly wired the injectors not through a switched source. Alternatively the loom may have been damaged somewhere - need to trace it back with a multimeter.

[XGTRX]

Someone may have directly wired the injectors not through a switched source. Alternatively the loom may have been damaged somewhere - need to trace it back with a multimeter.

Exactly right. Someone has rewired the constant power to a battery source due to a loom problem. Just find the wire and put a relay on it with an ignition supply.

Common and easy fix for ignition loom problems also.

Edited March 26, 2016 by XGTRX

[RRob]

All RB's have constant power to the injectors. If your ecu is a wire in model then it drop its outputs to ground whenit is off. The pnp vipecs dont have this issue.

[SiR_RB]

So I should strip back the loom and find the main positive supply cable for the injectors then wire a relay? Seems like an easy fix

Only shit thing is my loom is under the hypertune plenum, guess it has to come off again, unless that wire is on the ecu plug side in the passenger foot well ?

[SiR_RB]

Yes it's a wire in vipec v88

Thanks

[SiR_RB]

Obviously the loom gets a 12v power supply to run the show

Can anyone tell me where abouts this direct power feed comes from? I want to make sure no clown has connected any injector supply/control cables there

[GTSBoy]

The R32 GTR wiring diagram is on the net.

[SiR_RB]

Not familiar with reading wiring diagrams unfortunetly...

[89CAL]

There's a relay in the passenger footwell on R33's. Assume 32's would be the same. From memory power supply into the resistor pack and then it splits to the injectors individually from there

Grounded individually through the ECU on the way back.

Just had a look (at the R33) drawing, looks like power supply to the resistor comes straight from the key IGN

Grab meter and start probing. Maybe a wire has been mixed up on the ignition barrel

Edited March 27, 2016 by 89CAL