Why wont it start!!

[jamienshelly]

Hi all, just wondering if anyone has any pointers please. I have a 94 400 with lucas ignition.
Car started ok last night and went 200 yards to a junction and cut out, tried to restart but only turned over and no hint of fireing, thought it may be flooded but no smell of petrol around engine or exhaust as i have had this before. checked for a spark and ok, fuel pump running ok.
Looked at it this morning and found i have no voltage at injectors and rev counter does not move on cranking, checked the resistor contacts from the coil(under the breather pipe) and appears to be ok and voltage to and from, checked the tin relays and they are beyond their best. i know one of them powers the fuel pump but do they power the injectors? and what else do they power as may try to bridge them just for diagnosis only.
Many thanks Jamie

Edited by jamienshelly on Sunday 23 December 14:00

[Bassfiend]

I might be wrong and I'm sure that someone will put me right if I am but I *BELIEVE* that the injectors should be supplied with a permanent 12v when the ignition is on as the ECU simply provides a switched path to ground to "fire" the injectors. (That's certainly how my CANEMS works...)

So, with the ignition on I'd expect to find a steady 12v feed to the injectors...

Phil

[loud430]

the two metal relays are for the fuel pump & ecu.

[jamienshelly]

Thankyou phill and paul, I have no voltage at the injectors so would seem that fuel relay is shot just wanted to bypass relays to try and get it started, but seems strange both relays going at same time.
I will have to carry on testing and working the wiring out.
Many thanks Jamie

[jamienshelly]

Thanks for your help, have done it now found both relays knackered, strange i know but thats a tvr i suppose, bridged them both and fired straight up.
Thanks again
Jamie

[pb450]

Have you tried the alarm / immobiliser??

[jamienshelly]

pb450 said:

Have you tried the alarm / immobiliser??

Hi, yeah i thought that as the central locking packed up last weekend, but have stripped the relays down and i am suprised that they have worked at all in 2012, Just need to source 2 new ones now.
Jamie

[Bassfiend]

The "new" versions of those are brown plastic cased units rather than the metal cased ones ...

I should have a couple in the garage somewhere still attached to the old 14CUX wiring harness but to be honest it's bloody cold out and I haven't even been able to pluck up the enthusiasm to go check the oil and water in advance of my drive up north tomorrow for Xmas...

[loud430]

well done jamie, its nice when its something simple!

[jamienshelly]

Thanks again Paul and Phill, Been pulling my hair out all day and i didn't have a lot to start with. Have a nice and safe drive up north and wishing you both a very merry Christmas and a Happy new Year
Many thanks Jamie