GCU (ECU?) wires to Injection Pump and Vacuum Relays

[Jordan]

From the GCU there are 2 wires (Black/yellow and Black/Red) that go to vacuum relays and 3 wires that go to a plug on the IP (Black and 2 Black/silver). What are these sending to the glow plug control unit?

Any insight is appreciated!

[FalcoColumbarius]

Hey Jordan, how'sitgoin',eh? Have you looked in the Engine Electrical [16-39] in the L300 Dedicated Category Reference Forum? There's a section on the Glow System.

Falco.

[Jordan]

Thanks for the reply, I have looked through the manual, it shows the wires in the glow plug and EGT sections. What else uses the vacuum relays? If the EGT is deleted does the GPU do anything after the startup sequence?

[lrp374]

I know the vacuum relay on the left in the first picture is for the EGR. If your EGR doesn't leak disconnecting that relay is the same as a blanking plate. I'm not sure about the second one. It may be part of the system to increase the idle when the A/C is on. I'll review drawings I have and if I find out I'll let you know.

Larry

[Jordan]

I took the relay off for the EGT when it was deleted, it was on the far left, theres normally 3 in that spot. The relay for the AC Idle was also removed when I removed the aircon system, it was on the passenger side of the engine bay.

[Jordan]

each relay has a wire black w/white stripe and silver dots that go to the injection pump. The other 2 wires go to the GCU and are 'black w/ red stripe and silver dots' and 'black with yellow stripe and silver dots.

[Jordan]

Is there any information on the vacuum system? I can't seem to find any.

[FalcoColumbarius]

Is there any information on the vacuum system? I can't seem to find any.

I'm a total noob on this subject, so this is pretty much where I'm at: http://en.wikipedia.org/wiki/Manifold_vacuum

Falco.