Engine not starting

[Sonic]

Hi,

Over the last couple of days ive been having an ever increasing problem with the engine not starting when i turn on the ignition. There is no turn over or sound at all. Not a knatts fart.

The problem started several days ago when it didn't start first time, ever increasing up till today where i was sat outside work for an hour trying to get the car started to get home!

When i turn on the ignition to point 1 there are 4 lights displayed - the battery, handbrake, ABS and another one which i believe is for the immobiliser (a car outline with a key at the bottom, an orange light in the bottom left). The ABS and immobiliser stay on for 3 or 4 seconds then go off. When i turn the key again to start the engine nothing happens.

I can try again, and again and again with no results, then randomly it will start up. Could be 5 minutes, today it was an hour.

Another strange thing is that when its started, if i stop the engine it will start up again without a fuss. Its only when its been left for an hour or more than it causes trouble.

I figure that the problem is most likely due to the Audi immobiliser as the light comes on the dash and there isn't even a cough from the engine.

I have a cobra after market immobiliser as well and this works as expected. A little more background, i had a milltek turbo back system installed several weeks before and the aux coolant pump replaced. More importantly, the input into the radiator snapped the other day disconnecting the hose and spraying hot coolant into the engine bay.

My best guess is that the coolant has shorted something or damaged a sensor, giving false readings to the ECU which may be keeping the immobiliser active?

Any other ideas!?

[ericd]

I'd stick vag-com on it if you have it , just in case you have logged something , does sound like the immo, you got a reset option or a key for the immob?, otherwise I'd be tempted to take away the 12v supply , touch the +ve & -ve leads together for a few secs and connect it back up and try again.

[topsparky]

have you tried the ignition swich mate
might be on it's way out

[Fat Audi 80]

my money was going to be on the ignition switch too.... Easyish part to check. If you are hearing NOTHING, I suspect it is going to be an imobiliser / ignition switch problem otherwise you would hear the engine turn over and not fire etc....

Good luck.

Cheers,

Steve.

P.S. Next time it does it, you could try calling the RAC / AA if you are member and get an initial diagnosis from them.

[newsh]

Gets my vote too. Ignition switches are prone to this on these cars, particularly if you have a big bunch of keys, apparently. You dont have to replace the lock part, just the switch on the back of it. Could be wrong though.

[topsparky]

here a like to one on the bay
linky

[220bhp]

This has happend to me a few times, it happend again today,the small wire on the starting motor vibrated of, its a spade connector and it fits on the top of the starting motor. lay on your back with your legs pointing to the back of the car,put your arm up and you should feal it .

[4WheelDrifter]

I've had this problem before too, although not on the S2. All the lights come on, but the car wouldn't start. Leave it for 5 minutes to an hour or two and it would.
As Lou said it was the cable to the starter motor. I went to take it off to test for continuity and the cable was loose in the connector.

It's a long shot, but see if you can get a multimeter on the starter cable when it’s playing up.

[Sonic]

Well its been a week and i had the guy who does all the other mechanical work on my care look at the car this morning.

He said there was no problem with the ignition switch or starter motor. He by-passed part of the cobra immobiliser which allowed the engine to turn over but not start.

His words were that he was 99% certain that the cobra immobiliser is not disengaging correctly, allowing the starter motor or fuel pump to work. I spoke to cobra and then onto a place that specialises in them near where i live.

Ironically they said they were 99% sure that the cobra immobiliser was working correctly as the LED was going off and the car was unlocking, and that is was most likely the stock system.

Does anyway know if the stock immobiliser disables the starter motor or fuel pump (because if not it has to be the cobra), and if the cobra locks the starter motor and/or fuel pump?

I would *REALLY* like to get my hands on a wiring diagram for the cobra system so that i can get around it if anyone has one or knows where to get one?

I want my s2 back, im fed up of driving around in a focus diesel

[s20ale]

Just to throw a different light on it. I had a similar problem all be it a scorpion system
turned out to be faulty interior movement sensor cutting ignition, strange cos it never sounded alarm when standing.
Process of elimination really diss off each part ie door sensor,interior & voltage drop.
I was fortunate to have full wiring and istallation diagrams though.
Good luck mate it can be arpita.

[Sonic]

When i cover both door sensors, put the key in the ignition and turn it - IT WORKS!

If i try it putting the key in before covering the sensors it doesnt work. I will be on the phone to that cobra guy tomorrow to sort it out!

BUT....

Whilst it made my spine shiver driving the s2 for the first time in a couple of weeks, i made it 10 miles down the road to asda to top up the tyres, and whilst half way round noticed steam pouring out of the engine bay (ala hose comming off radiator http://s2forum.com/forum/showthread.php?t=25633)

There was some ***** in an asda fuel lorry behind me waiting to be where i was doing my tyres, to fill up the fuel. I told him i wasnt going to start the engine and he said hed push me out the way with his lorry.. to which my reply was **** **** .

Got him to give me a hand pushing it out the way (with the girlfriend whos never touched a steering wheel before turning a corner ) and went shopping whilst i waited for my house mate to arrive with a socket set to re-tighten the juliet clip.

Mate arrive, put hose back on, filled up with coolant and pottered home...

Got home, noticed there was cold air comming out of the vents and the coolant light came on as i began to smell the hot engine pulling up the drive. Cranked open the bonnet - hose off, no coolant

Now, the problem is that im not mechanical and have never really dealt with engines or anything. I spent the next hour and 12 litres of water trying to get liquid flowing round the coolant system. For the first 20 minutes the neighbours must have thought i had a steam engine on the drive as i took out the radiator bleed valve and kept the coolant tank top off to flush water through the system, bring down the temps and stop the hose popping off again.

Got all the temps down, water flowing round the coolant system and hot air coming through the vents. In hindsight i see that when the hose came off at asda the system would have air locked, so topping it up with coolant did sweet FA.

Now just to wait until tomorrow to see if the coolant tank is empty and if ive destroyed the head gasket

Off to get a stiff drink.....

[KaraK]

the plume of steam was very impressive... it was like some sort of industrial accident! I was also pretty scary when the hose came off after we first filled it back with coolant on the drive. It was like someone had set off a steam grenade!

Still all that running to fetch more water gave me some exercise!

[KaraK]

Off to get a stiff drink.....

I reckon that for the first time ever if I had placed a glass of whiskey in your hands you might have downed it!

[Laurel]

Good Grief! Are you talking about your S2 Andy?

[Fat Audi 80]

To bleed, run the car with the expansion cap OFF. Top up as desired, keeping the mixture of coolant and water correct and after the fan has cut in a couple of times replace expansion bottle cap and you are away.

Works for me.

Hope that helps.

Cheers,

Steve.