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Can You Help Me Identify This Plug? Wiring R32 Rb20Det

Willis

By Willis,
in General Maintenance

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jiffo Mentor

jiffo

Posted
Posted

Yes the Air Reg is the fast idle device.

It's buried under the plenum, is a 12V bi-metallic strip valve and you mentioned that it's all plumbed in anyway.

The resistor mounts to the left strut tower and the air reg won't work electrically without the resistor, but it will close from engine bay heat regardless.

It's one item I always block off on my Rb's, simply not need in my climate.

The MAP sensor for the factory boost gauge has no input to the ecu, it only works the in-dash boost gauge.

I'd need more info on that other taped up harness to give an opinion.

Willis Proficient

Willis

Posted
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Posted

Put a wire between the connections at the base of the relay to pretend it's the relay.

Alright I will give that a go.

Done. Fuel pump works.

Filled my 1.25L bottle attached to the lines in a hurry!

I checked the relay again, it has power on one relay pin. No earth on the other side.

The ECU switches the earth when certain criteria are met to power the fuel pump?

For 5 seconds for prime, then upon a signal from the CAS?

Willis Proficient

Willis

Posted
  • Author
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Thanks for the suggestion Ben.

Alright so I guess from here I will continuity check the earth line from the Fuel Pump Relay to ECU pin #18.

If there is continuity, that means everything back from the ECU is fine.

Does anyone know the criteria that the ECU requires to switch the fuel pump earth?

Willis Proficient

Willis

Posted
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Posted

Pin 43.

Start signal to starter solenoid. (when IGN key is turned to the start position)

Thank you for that, I will investigate this tomorrow. What should I expect on Pin #43 when the IGN key is turned to start?

The engine cranks.

It's possible for it to crank but not have the start signal?

jiffo Mentor

jiffo

Posted
Posted

Pin 43 will receive a 12V positive input to the ecu, when the IGN key is turned to the start position.

I'm not understanding your problems, thread has wandered a bit since the initial question so perhaps you could give us an update of where you're at now.

Willis Proficient

Willis

Posted
  • Author
Posted

Thank you for all the reply's btw!

Still working on this car.

It won't start, figured I would just add a post to this thread instead of starting a new.

I've got a few plugs that I would like identified ^_^

Not starting symptoms;

There is no fuel, i've pulled the lines off and cranked the car over. Nothing comes out.

Initially replaced the fuel pump as I assumed it might have died.

Still no fuel.

Checked fuses, all good.

Checked fuel pump relay in the boot, and the 2 x ign and acc relays in the passenger footwell.

ECU displays a solid red light with accessories on.

Goes out when cranking.

Not sure if this is normal?

attachicon.gifIMG_4261.JPG

attachicon.gifIMG_4262.JPG

Engine cranks, but doesn't fire. (no fuel obv)

The following plugs are unplugged, as i can't find a home for them.

This one, it's near the power steering fluid reseviour;

attachicon.gifIMG_4257.JPG

attachicon.gifIMG_4258.JPG

attachicon.gifIMG_4259.JPG

And this one near the brake master cylinder;

attachicon.gifIMG_4263.JPG

attachicon.gifIMG_4264.JPG

Also i'm not sure where this wire goes, is it an earth?

attachicon.gifIMG_4256.JPG

Any idea's, or plug identification would be fantastic!

I had hoped that the ECU had no power or something easy, but alas the light made me sad!

Cheers! :D

Here is where i'm up to jiffo.

Yes the thread has wandered, I guess I should have made a new one?

Last night I bridged the fuel pump relay with a wire as suggested and the fuel pump worked.

I do believe this means the issues is with the fuel relay control signal from the ECU?

Willis Proficient

Willis

Posted
  • Author
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At this stage I believe that the cause for issue is my ECU.

I borrowed a mate's R33 ECU and the fuel pump prime's, appears to work correctly.

Car cranks and starts but die's after a few seconds.

Once I get a r32 replacement ECU I will continue to troubleshoot.

Thanks for your input

Willis

Willis Proficient

Willis

Posted
  • Author
Posted

Alright so tonight I put in a 32 GTST ECU, fuel pump primes correctly. Unlike my old R32 ECU.

Car won't start however.

Cranks, a few cylinders fire. Then dies.

AFM is unplugged.

Swapped out the CAS.

No change.

I'm putting in fresh fuel tomorrow to eliminate that unlikely potential.

I guess I'll track down a fresh fuel filter also.

I've yet remove the CAS and spin and listen for injector tick etc.. guess that's tomorrow also.

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