Help with Zetec problem on my Westie

[davidstanley]

Ive got a 1800 Zetec running on 45 webers with an Alpha P1150 management system. Its been running fine and done 3000 miles.

Over the last week ive had problems starting the car with No or very infrequent spark from the plugs.

Ive checked the ignition coil and its fine. Ive checked it in my mates Westie and all is good. My battery is charged fine, and all fuses appear ok.

Any ideas???? Could it be anything to do wit hthe Alpha system , although surely if the ECU has failed it wouldn't start at all.. When it does finally start, its running fine..

Is any software available for my own diagnostic's?

Please help if you can, i need to get my westie back on the road.

ps, i've definately got fuel getting through to the carbs .

cheers

dave

[Furyous]

davidstanley said:

Any ideas???? Could it be anything to do wit hthe Alpha system , although surely if the ECU has failed it wouldn't start at all.. When it does finally start, its running fine..

dave

Dont know that sytem, but does it boost the spark during start up ? does the battery voltage remain good during cranking ? Check the earths, Ive seen earth leads that broke contact when the motor was being cranked/revved.


eta- can you bypass it and still get a spark ?

Edited by Furyous on Sunday 25th February 13:18

[davidstanley]

thanks for the update. i've checked all the earth connections which look ok, although that did go through my mind as well. i'll check the battery output tonight, although it seems fine and is turning over very easy.

Could it be the crack shaft sensor? would that send a false reading to the ECU and cause it not to send the spark signal?

Ive been racking my brains again last night. I did manage to get it started once yesterday, but no luck again afterwards.

[knightly]

remove the crank sensor from the engine and make sure its not attracted a shed load of iron filings from the clutch plate, which will give a bum crank signal......a common problem on zetecs.......shove an air line in and blast it out for good measure.

once you have done that......check all wiring loom connections......the alpha looms suffer bad reliability problems from faulty wiring connections in the loom manufacturing process.......particularly the big connector that go's into the ECU - I seem to remember 1 screw and the plastic ECU multi-pin socket cover will easily come off.......then go around the rest of the sensors on the crank, water, air and throttle potentiometer sockets, and check they are OK.

if none of that works, forget about playing with the ECU with some software on a laptop......only Alpha dealers and Alpha factory should do that.......either go to an alpha dealer, or contact alpha direct and ask to speak to Alan Collins.......I would advise you do the latter ;-)

[davidstanley]

cheers for the help guys.

ive replaced the crank sensor this week, but with no luck. the wiring harnesss is from westfield and appears fine.

i've also checked and double checked the multi plug into the alpha unit..

its not even trying to fire now, even though the ingitition unit is ok.

what voltage should i get on the ignition when i crank it? i'm getting a constaint 12 v on the middle supply cable, but voltages of 2v on the other 2? does that sound right.

i think i'm left with taking the alpha out and finding a specialist to check it for me.

cheers guys dave