Mk1 16v not starting - help needed!!!

[donsrno1]

As some of you may have seen I am having a right ballache with the valver. Basically the car will not start and the reason for it is that the injectors are not firing. I have checked the voltage at the injectors and they are only getting about 0.1v to the injectors. I have checked as many sensors as I can and they all seem to be OK. This left me thinking that the ECU was at fault but having changed that it is still doing the same thing. The car continues to spark as normal, but does not have any fuel as the injectors do not fire.

So far I have changed the ignition module and the ECU without any change. Has anyone else had a similar thing happen, and if so what was the cause?

What suggestions has anyone got for what I can try/check? I really am in need of some help as I'm getting nowhere with it and have hit a bit of a dead end.

Thanks.

 

[tim124]

With the ignition on the injectors should have battery voltage on one pin and pulse to earth on the other. If your injectors dont have 12v on one of the pins then its either a fuse or a relay gone somewhere

 

[donsrno1]

well, using a voltmeter across the pins of the loom connector when cranking I was getting 0.1v. IIRC there was no voltage when it wasn't cranking. I would have thought that if it had the voltage as you described then the injector would constantly be firing??

 

[tim124]

you need to measure from ground (negative battery) to each of the injector pins seperatly. one of them should read 12v and the other will pulse to ground but too fast for you to be able to measure with a normal multimeter.

yes if the injectors were fully open (ie 100% duty) then you would get 12v between the two pins, but the engine would have to be maxed out to read this.

From what you are saying the 0.1v could be your meter averaging the pulses coming to the injectors but the tests above would be more conclusive.

Try pulling the injectors including the fuel rail out and see if they are actually squirting fuel (be careful you dont go up in smoke). it could be your fuel pump not supplying fuel?