here we go again - part 4

[uglymug]

been at it all night. it wants to start in the first couple of seconds, but after that it just cranks over.
it seems that it is not getting any petrol after a few secs. as i manually click inj's by throttle at least 10 times it nearly goes. after that nothing. as the cold start inj does not work i am not able to chuck more petrol in. will try some cold start spray tomorrow.
could this be anything to do with the ECU as it controls the inj's. could this ahve been affected by the battery reconnection the other day.

[blaineuk]

is there anyone local to you that you could swap the ecu with

[jmorgan]

During my plug mare of a time I was charging and discahrging the battery like crazy. I was infromed that disconnecting etc will not affect the ECU normally.

[uglymug]

umm- dickymint is the only one really, but i dont like asking just in case mine knackers his car up!!

[jmorgan]

Mine is a hot wire, will that work?

[wedg1e]

Worst case scenario, I'll send you an ECU down.

[dickymint]

Can pop over Sunday no problem. Mail me your number just in case i can't find it.

[350matt]

check fuel pressure as well

[Number 7]

Try wiring the fuel pump direct to a live feed?

7.

[mikeb]

Are you sure you ain't got a black box of tricks left over from a previous alarm/immobiliser still wired in there someplace?

I pulled out three boxes out of mine still half wired in!

MikeB

[grahamw48]

I was thinking along the same lines.
The sort of electronic gizmos likely to be upset by battery disconnection ?
You used to be able to get gadgets that cut off the fuel supply.
Does something need resetting ?

Oh for the days of 'bumping off' down the nearest slope.

Damned 'twocers' caused all this.

Should all be castrated !

[uglymug]

no hidden boxes of tricks anywhere. To be honest I went thru all that the first time I could not get it started

[adam quantrill]

OK, back to basics.

What does an engine need to fire up?

1. Motion
2. Air
3. Sparks
4. Fuel

1 - it turns over.

2. - not much can go wrong here, but to be on the safe side, remove the air filter. Check for dead mice etc.
You might also do a compression test (it won't be great when cold, but maybe there is a bust exhaust valve?).

3. - Take off each plug lead in turn & check for sparking to a convenient earth. The spark timing is also important, so check with a strobe.

4. Fuel. Not too much, and not too little. Disconnect the feed and run into a measure, and time it. Got a fuel pressure guage? Check it/set the pressure up - the pressure regulator might be busted. Test the engine temperature sensor at the ECU multiplug (also checks the wiring). Check that the voltage on the throttle pot varies smoothly. Check for air leaks on the inlet side.
If you have an oscilloscope check the injector pulsing mark/space ratio.

[Gerry Attrick]

If you've not done it, I favour Paul's idea of connecting the fuel pump to a constant live, in case it's switching off when it fires up. Can't think of anything else.

[nigel_350i]

IIRC the air flow meter has a switch that keeps the fuel pump on when not cranking. Check by ignition on, manually plus the flap forward and you should hear the pump.

[uglymug]

I am afraid that I have done all that...

[tallbloke]

Mark:
did you try the extra battery coupled in parallel?
Did you try getting it to fire with ether/easystart and the fuel off?
Often a duff battery will give an apparently good spark on a plug lying on top of a cylinder, but will fail under compression. I suspect your problem is a combination of overfuelling and weak sparks. When was the timing checked? Has it slipped?

[dickymint]

Duff battery could be the answer.
Also just remembered that my 350 has an alarm that even though its switched off still needs the feed (direct from battery) to it - havent left a wire off by any chance?

PS. See you tonight with your ECU ?

[uglymug]

Tryed the back to back battery method. No good. Will try the "easystart stuff" tonight. Hope its not raining too hard Dickymint.

[tallbloke]

Try disconnecting your battery and just connect the second battery onto the battery leads with some good jump leads, sometimes a duff battery can act as a ballast resistor and pull down the good battery too.

Good luck be with you.