Help! Car won't start!

[Rusty]

Just got in from the garage and have a major problem. The car will not start. It turns over but will not fire.

I got in this evening and decided to swap the knock sensors back to the original ones as I've been havig a few problems with full boost running lately. Swapped one knock sensor over, went for a drive, came back as the same problem was still there. Swapped t'other knock sensor over and then disconnected the ECU from the plug to reset it in case it had stored any faults. Re-connected it and then went to start the engine, turns over but doesn't fire. ******...

I've tried a different ECU with no joy, different MAF, I've checked the fuses in the fuse box, the fuses under the dash and none are blown. I've checked as many plugs as I can see although why they'd go god only knows! The immobiliser is still functioning but I haven't checked hte outputs. I've checked the pins on the ECU wiring loom for power and it seems to be fine.

Basically I'm completely phooked, not thinking straight, tired and trying to figure out how to get to work other than on 2 feet or 2 wheels.

Any sugestions welcome, looking at a day or two off work to try and sort this and yes, I am panicing like a mofo.

[Cullam3n]

Will it start if you bump start?

[Rusty]

Not tried bump starting as it turns over fine, need to identify if it has a spark or fuel.

[Fat Audi 80]

Calm down dear...

Have you replaced both knock sensors now? If you have, I would put them back to normal.

Put your car back to how it was working last time and try again.

If you have already done that then try the "water in the back of the cam pulley trick" it could be your cam position sensor.

Let us know how you get on.

Cheers,

Steve.

[Rusty]

The what trick? link?

[Acidburn]

there was a thread ages ago for testing the sensor by pouring a small amount of water down the back of the cam pulley which for some reason helped/made the car start.

[merlin's S4]

Search for threads regarding the "hall sender". Dan had this problem (Dpicariello) with his S2 not starting intermittantly. The hall sender can start to fail with the heat so as a quick fix you can pour water down the back of the cam cover to cool it down enough to start the car again!

[Acidburn]

Not sure if this will apply that much as depends how long and how hot the car got, probably cooled down abit to change the knock sensors but worth a shot.

[r1alex]

andy just check the speed sensor connector to the left of the knock sensor connections, incase you have dislodged it it won't start if you have, i know cause when I changed the im gasket last weekend ,and was tidying up the wiring whilst i could get at it, withe the im off i left that one not properly connected , it would,nt start, just turned over and over,I too had a nervous breakdown.

[Jas11n]

I agree with Alex, you've also got the crankshaft sensor there too. That not connected and it'll turn over all day with no spark.

[terrybullwon]

I agree with Alex, you've also got the crankshaft sensor there too. That not connected and it'll turn over all day with no spark.

As Jas said, but also check to see if the pin is still on the fly wheel so it can take a messurement with out this the sensor will send signal but the car will not fire.

[Rusty]

Got it started but have no idea what I did to change anything. Disconnected, inspected and re-connected every sensor I could get my hands on and more besides.

Anyway, have to see what happens but I am temporarily relieved!

[baltiboyS2]

Keep a eye on the hall sender behind the pulley the fault could raise its ugly head again
Nice one on getting it running again

Raj ABY

[S2central.net]

Maybe you have some intermittent wiring fault Andy... Might explain the recent bad running you have experienced - like if G4, G28 or G40 aren't properly connected all the time - or the sensors themselves are acting up !

[Rusty]

It's going to need a good Vagcom ing soon. It's not running badly, just not right!