VR Computer?

[Torniquet]

Gday guys, i was playing around with a car from work for about an hr or so (just got home).

its a VS commo V6, and basically it wont start. It has spark, heaps of fuel pressure. It has injection pulse. whilst cranking the car backfires and carries on.

i only had a quick look at it before i left to come home. But no1 else could figure the problem out. the apprentice told me it had spark, fuel pressure and injection pulse. WHen i checked them all over again i noticed the injection pulse was all over the place?..sometimes it would have it and other times it wouldnt..when using the noid test light i noticed sometimes the pulse would be realli quick then it would slow right back down. has anyone else noticed this before?..

i used a test coilpack and dfi module, and the cas is good.

any ideas?

 

[Not_An_Abba_Fan]

ECU probably. Do you have another one to put in and try?

 

[Torniquet]

apparently one of the boys did try another computer and it didnt help.

too me it does sound like ecu. but apparently not..

 

[kopper69]

So you can hear the fuel pump prime when you turn the key and there is a signal at the injectors?

 

[Torniquet]

fuel pump is priming. put the fuel flow + pressure gauge on it and its all good.

the injectors do have a signal, but as i said its not a consistent signal. the speed of the signal whilst cranking changes..fast to slow..and sometimes not there at all

 

[Not_An_Abba_Fan]

If it wasn't sparking does the ECU interrupt the injector pulse?

Oil pressure sender maybe, that is linked to the fuel pump circuit. Worth a try.

 

[14secvp]

the injection gets its pulses from the dfi module and cas ide be thinking its something to do with them or the balancer has moved on the keyway or is just knackered and not timed right youll still get spark but at the wrong time and intermitant injector pulses

 

[14secvp]

the ecu doesnt control spark at crank its just the dfi spitting out 10 degrees of timing advance to the plugs

 

[Not_An_Abba_Fan]

Thats sort of what I was thinking. If the DFI didn't fire, the injectors wouldn't pulse or they would be intermittent.

 

[14secvp]

but I now read its a vs dont they have a camshaft sensor as well for sequential injection could be the culprit