Recently done a swap from 1997 1.6 - VR6 obd2 Before the swap fuel pump would prime with ignition on and switch off after a couple seconds. Now I have fitted vr engine and loom fuel pump is constantly on with ignition. I have scan the car and getting coms from ECU which shows coolant sensor and immobilizer fault. Could immo cause this problem.
Using 2 fuel pump relays number 167 and both are doing the same things which is making this even more confusing may pick up another brand new one and see what happens
this is handled by the ecu which triggers the 67/80/167 fuel relay, one thing you might want to check for is a 2 pin plug inline with the fuel relay trigger to G1./3. this plug is there for retrofit alarm/immobilisers, and on cars without just has a looped plug fitted. If something else random got plugged in this coudl explain:
I I have g1/03 blue and yellow but this seems to run from fusebox directly to ECU. Only red plug I seem to have is single pin brown and red Will try and figure out how to upload some pictures
Ok no worries on that front then, not all mk3 had the plug on. Does it still do it wh n ecu is unplugged?
II am just reconnecting fuse box back up after a deeper search for the wire but will try it with ECU not connected and with relay 30 removed
relay 30 is the reason. the later VR6 loom has a wire in G1/10, which is powered by relay 30 but this wire is not actually needed on the vr6 loom (but why is it there then? who knows?) the problem is, this wire is also tapped into the same fuel relay power feed from Z/1 which then powers all the engine electrics. In a nutshell, if you have a 30 relay in slot 3 in a late VR6, this will back feed the engine electrics and fuel pump circuits
So gave it a crank fuel pump switched on so seems to have done the job. Didn't realise fuel pump didn't prime on this as on my 8v fuel pump primed so guessed it should be the same Next to get some fuel in and see if we fire up Thanks for you help mate been all over the inter to find this info out
