S2 ABY Wont start

[S2central.net]

Couple of pointers....

1 - fuel pump does NOT prime on S2 so thats not a worry

2 - search the forum on building a fuel pump 'hacktivator' so you can test fuel delivery without running the engine

3 - the fact that S25 blows on cranking says a couple of things... firstly that pump relay is getting activated by ECU - which means it is broadly happy with RPM signal from G28 sensor... and secondly that some odd **** is happening cos either a loom fault is creating a short circuit on the S25 path - or the lambda probe heater itself is shorted.

4 - with ignition on, check you get 12V at one side of the fuel injectors and that the white 3-pin plugs on the POS connectors are also 12V.

Oscilloscope is the only way to ascertain if G4, G28 & G40 are healthy and aligned... I have posted plots of that in the past which will help any auto spark worth his salt even if he doesnt know any specifics on S2 wiring and such.

Are you certain its not some immo/security issue ?

[Biggss2]

Aaah cheers James.. Thanks ever so much for your help that day was really kind of you considering I wasn't even a forum member yet! I'm hoping there Is light at the end of the tunnel!

[Biggss2]

Paul.. The thing that worries me is there is a big ugly laserline box on the car with some wires fuses going to it I'm not really comfortable with messing as I don't want to make the issue worse.. The car itself ran fine until it give up ghost one day. I'm going to check the timing via bell housing tomorrow.. Hall sensor seems fine as I've got it where I can disconnect it no spark connect it and get a weak spark. Would it help me replacing the lambda sensor or is this a lost cause right now?

As for changing the loom I'm guessing that a) it's going to be a complete pig of a job and b) the loom itself is going to be as rare as hens teeth

[S2central.net]

Ignore lambda probe for now... unless you have a multimeter you can use to test the blighter ?

Laserline immo - yeah - its a worry alright... these things are easy when i am hands on - but describing every step of electrical tests to anyone who is not comfortable around electrics is horribly complicated and subject to confusion.

You suggest you are seeing 'weak sparks' now - that kind of rules out ECU control logic and G40 as thats either a go or no-go decision based on presence of RPM and CMP signals. If spark is weak then it suggests a problem with 12V supply to the POS units or a bad earth from the coils - check the fat brown cable coming from coilpack cover is nice and tightly grounded to top of engine.

The immo could be interfering with 12V power to coils or the ECU... can you privately send me the colours of wires that the immo is wired to - on the fcatory loom I mean ?????

[Jonnybravo]

Aaah cheers James.. Thanks ever so much for your help that day was really kind of you considering I wasn't even a forum member yet! I'm hoping there Is light at the end of the tunnel!

No problem at all, Paul will see you right when it comes to the electrics ! very complicated stuff but he certainly knows his way through it.

[newsh]

If the immo box has a multipin connector on it, pull it out and check there are no black pins or signs of heat.

[Biggss2]

It has a multipin connector and with that it has 4 yellow wires that have 2x 5amp fuses on them.. How hard would it be to disconnect the immobilizer and throw it away?! The thing that gets me is that upon cranking the engine sounds so healthy and as if it wants to go!

[Biggss2]

To do

Check timing on bell housing/flywheel looking for a 0 mark

Check the plug on dreaded immo box for heat damage/black marks

On the backburner: CPS (was so close to splashing out £130.00 from tps today until I read pauls thread on non starters) & lambda sensor

Guys where I'd be without you.. Heavily out of pocket and Quite simply without an s2!

Can't thank you enough

[newsh]

Add to list, activate fuel pump to see if it runs. Bridge contacts or pull the top off the appropriate relay and close the contacts by hand.

If car ran fine and one day would not start it could be the fuel pump died, my avant went like this. Started the car, it ran for 10 secs and died, would not restart.

Its strange that 2 plugs were wet and 2 were dry (and what about the 5th? )

I have removed a few immobs and alarms, it a matter of following the wires from the immob box back to where they've been spliced into the loom and repairing the loom back to stock. Usually at the ignition switch and at the ECU. If you have total closure then you will have wires in the door jams too which is a bit more messy ..

[Biggss2]

Hmm il give the relay a go Aswell... with the plugs I disconnected them to check for a spark they kind of smelt like petrol but the last couple were oily :$ I've stumbled across Pauls loom/wiring diagram this will be really useful should I decide to scrap the immobilizer!

[Biggss2]

Update: fuel pump out.. Looked at... Back in and the car............... Wait for it......... has started!!!!

Main problem sorted.. Now moving on to the lambda that keeps blowing fuse and the fan
That is doing overtime

What a silly little problem causing soo much confusion

Also the auxiliary rad is shot so il be looking to source one of them too..

So glad it's started thanks everyone for all your help it has been emotional

[Jonnybravo]

I've got what looks to be a good auxillary rad mate

[Biggss2]

How much posted mate? I've sourced one locally visually it looks smaller but has the same mounting points as the one that's come off the car?!

[Jonnybravo]

£30 mate, let me double check it first for you.

[Biggss2]

Yep that's fine James check it if it's alright il take it off you