Won't start - any ideas?

[Scrooloose]

She's refusing to start. Battery is fine, starter is turning, fuel is pumping, but there's no spark.

I've checked all the fuses, there isn't a 100A fuse on my system.

Bloke from the RAC was stumped, so am I. Anyone got any ideas?

[TT Tim]

Scrooloose said:

S...there isn't a 100A fuse on my system.

Do you mean that?

The 100A fuse is sited at the back of the engine on top of the bellhousing.

Not sure it would give the symptoms you've described, but did wonder if you knew where to look for the 100A.

Good luck

Tim

[Ireland]

Coil-pack, perhaps?

[jonbarrett]

I've never tried turning it, but what about the imobiliser key hidden under the dash. Maybe that knocks the spark out. Doubt it but just a thought.

[Scrooloose]

TT Tim said:

Scrooloose said:

S...there isn't a 100A fuse on my system.

Do you mean that?

The 100A fuse is sited at the back of the engine on top of the bellhousing.

Not sure it would give the symptoms you've described, but did wonder if you knew where to look for the 100A.

Good luck

Tim

Yep - I discovered it's absence when changing the starter motor.

It's not the coil packs as there would be some evidence of misfiring on at least one bank.

I haven't tried the silver key yet - will give that a try tomorrow.

[FUBAR]

Doesnt the silver key cut the electrics? So if its turning over it has power?

[Ireland]

The silver key kills everything.

[ridds]

Basics.

Pull a plug out. See if there's spark.

Also whilst out have a sniff for fuel. If you have both there's no real reason why it should not at least fire.

[Scrooloose]

ridds said:

Basics.

Pull a plug out. See if there's spark.

Also whilst out have a sniff for fuel. If you have both there's no real reason why it should not at least fire.

As per first post. No spark..... but can''t figure out why not

[jbvipercerb]

Maybe crank sensor? Take it out and clean it and the plug. I don't know what voltage there supposed to put out, or how to check it but if the ecu doesn't know when to fire it won't???

[brogenville]

The immobiliser doesnt just cut poer to starter and fuel pump, but it may well also prevent power from getting to the ignition system too. A screwey immobiliser would be my number 1 guess as to why a problem like this has come up. You could test for it by fimding the immobiliser and looking for a short circuit across each of the "cuts". Dont suppose anyone's got a diagram showing the connectors to the immobiliser?

[Scrooloose]

jbvipercerb said:

Maybe crank sensor? Take it out and clean it and the plug. I don't know what voltage there supposed to put out, or how to check it but if the ecu doesn't know when to fire it won't???

Sounds like it could be the culprit....

Can anyone tell me the exact location of the sensor please?

Pics would be even better!!

[Byker28i]

brogenville said:

The immobiliser doesnt just cut poer to starter and fuel pump, but it may well also prevent power from getting to the ignition system too. A screwey immobiliser would be my number 1 guess as to why a problem like this has come up. You could test for it by fimding the immobiliser and looking for a short circuit across each of the "cuts". Dont suppose anyone's got a diagram showing the connectors to the immobiliser?

I think that's the rear harness:
http://homepage.ntlworld.com/dave.hinns/wiring.htm

[Scrooloose]

Right. After a bit of further investigation, it looks like it may be the crank sensor.

If anyone else has this problem, if you take the wiring connector off the coil pack and remove the rubber boot, you can see two red wires. Whilst the ignition is on and working correctly, there will be 12 volts between these wires and earth. This confirms that it isn't a problem with the ignition system and immobiliser.

What this suggests is that the coilpack isn't receiving instructions to fire from the ecu.

So it could be two things, crank sensor or ecu. I'm hoping crank sensor. Unfortunately I don't have the original ecu to test it with.

If anyone in the Bournemouth area has got a spare one I could borrow for a little while I'd be most grateful!

[ancol]

i had same problem albeit on a different make of car but the principle is the same and it was the crank senser changed it and all was fine again

[baguaman]

i am told that if the starter motor is on the way out ..it causes a drop in voltage and the car will turn over but not start/...what do u guys think to this..

[Scrooloose]

baguaman said:

i am told that if the starter motor is on the way out ..it causes a drop in voltage and the car will turn over but not start/...what do u guys think to this..

I've had that problem with a battery that was on the way out, but not a starter.....

The starter in mine is brand new, so it shouldn't be that....