This morning the wife was taking the kids to school when the car just cut out, it has been doing this on and off recently and refused to start just turning over so I checked all the fuses thinking of fuel pump etc but no fuses have blown.

I have had the codes read and it came back with cam sensor intermittant signal so I have had a new cam sensor fitted and it still refuses to start, all the wiring to this sensor has also been tested.

The worrying thing now is that nobody can cominicate with the engine ecu, the only systems that are talking are the ABS and the Airbag system but when you try and read the engine ecu it isnt communicating.

The car does fire up on rare occasions then dies very quickly, A bit like the imobliser is stopping it but the key light isnt flashing and have tried another set of keys also. The thing that I have noticed is that if i have my foot on the throttle and start the car sometimes it fires andgoes to 4k on the rev counter but then just dies so it seems that the fuel is getting to the engine but for some reason the car wont carry on running and just dies.

then most of the time there is nothing not even a hint of trying to fire up.

Any help is greatly apriciated as i am well and truley stuck now, and the annoying thing is that the car passed its MOT only 4 days ago.

Thanks again in advance for any help as I am stuck. :(

Edited 26 January, 201016 yr by justinbarrow

have you tried disconnecting the battery for ten mins or so?

I cant find the info at mo, but im sure i read that if you connect to the airbag module it will stop car from starting.

Wonder if the crank sensor gone on holiday.

but thats just a pure guess.

this link does not menstion not being able to start, but its somewhere, i have read ther is a procedure to do, cant find it.

http://www.ross-tech.com/vag-com/vw_issues.html

Check any fuses and the relay (relay 109?) for the engine ECU for a start.

Check any fuses and the relay (relay 109?) for the engine ECU for a start.

Thanks for the help, where is relay 109 located mate. how will i know if something is wrong with it? cheers.

Sounds very much like an immobiliser issue, try getting the keys re coded to the control unit, other possibilty could be a broken can bus wire to the engine control unit, do you have the standard head unit in the car ?

Is this car from the same post that asked "if it was smoking too much"? and this picture?

This is the state of the oil cap and top of engine oil cap, i only cleaned it off on Friday (2 days ago)

If so, you need to get it to a garage!

Edited 26 January, 201016 yr by smileonimpact

yes it is the same car, but its not got as much mayo now just a bit but still there, The water and oil levels are fine for now. I also have an aftermarket stereo fitted and none of the 3 keys I have work. the key light does not flash either.

One question I do want to ask is, will the car bring up a fault code indicating cam shaft sensor when its not the sensor, in other words if the car is not firing as it should will this mess the readings of the cam shaft sensor and bring up a fault code indicating the cam sensor. This error code was always present when the ecu was talking despite having a new sensor at £65 and the wiring checked.

Anyone thinking dodgy coil pack, but then this would bring up a code wouldnt it? wow this is unreal lol.

Thanks again everyone, you lot are stars

Maybe the fault is with Relay 109?

I think that this supplys power to the ECU amongst other things, so that could explain why you cannot communicate with the car as no power is getting to the ECU.

Just a thought.

To begin with you need to go right back to basics. Judging by the fact that it occasionally fires up I doubt there is a mechanical fault like cam belt slipped ect. Check if there is a spark at the plugs while cranking and that the fuel pump is pumping fuel. Not all non start situations need plug in diagnostic equipment to begin with...though admitidly most do!

I see it's a 1.6....I'm assuming it's a 16 valve model being a GLXi?

I see it's a 1.6....I'm assuming it's a 16 valve model being a GLXi?

No mate its a 1.6 8 Valve engine with the engine code AEH, There is a spark on cranking and also the fuel pump is hears running. For some reason the ecu was talking again this morning (its having its moments) and the code is 00515 (cam sensor) but I have had this replaced with the wires that rin to the plug.

thanks. again.

Edited 27 January, 201016 yr by justinbarrow

Sounds very much like the ecu relay to me. If the relay is buggered, it will sometimes work fine sometimes not and sometimes close breifly and then open again (allowing the car to start but then killig it). If it has failed, you would expect that VAG-COM wouldn't be able to see the ECU. If it is the immob then you should be able to read its status using VAG-COM (or at least you could on my old Golf VR6).

Cheers,

iep

ok back to basics time as dave said.if the ecu is not talking then its either not powering up (relay 109/fuse) or a databus fault. how long has the stereo been fitted? daft q i know but they can cause these type problems.

relay 109 is under the dash on drivers side. do a search on here for it,

ok it definatly has fuel in it?

and the correct fuel?

the cam sensor fault could be a CRANK sensor problem as the engine will run off either if one fails OR it could be telling you that the cam is timed incorrectly ie a tooth or more out on the belt as that will bring up a cam sensor fault too.

if the cam is a tooth out it MAY explain the excessive steam you were getting back in the cold..

so

1) check the cambelt for timing and condition 1st so no further damage is possibly caused.. simple job

2) if the belt/timing is good check out the relay, if you are handy with a soldering iron its an easy job to repair

3) if still no comms it maybe worth removing the ecu from its hidy hole and checking the wiring connections for water ingress and the earth wires by the battery for corrosion..

4) i'll give take a risk and give ya £100 for the car if you deliver it to me

UPDATE:

Got the car towed to the garage where they have told me that the head gasket is fine, but the engine isnt getting a spark and are going to look into this further tomorrrow. They are also having problems with reading the ecu and have said that if it is a case of the ecu then the car is scrap as it will cost hundreds to sort out.

They are going to look at the coil pack tomorrow, but the car was running when it stopped, they are also going to check for fuel blockages as at times the car will fire up rev to the 4,000 revs then just die again when it did this at the roadside they said it sounds like fuel starvation or blocked injectors :S

So it could be quite a few things but I am hoping that its not the ecu as this will be to expensive i feel. will know more tomorrow.

How much would a coil pack set me back as a rough idea? or something like a crank sensor just trying to get some idea of costs, cheers.

ok back to basics time as dave said.if the ecu is not talking then its either not powering up (relay 109/fuse) or a databus fault. how long has the stereo been fitted? daft q i know but they can cause these type problems.

relay 109 is under the dash on drivers side. do a search on here for it,

ok it definatly has fuel in it?

and the correct fuel?

the cam sensor fault could be a CRANK sensor problem as the engine will run off either if one fails OR it could be telling you that the cam is timed incorrectly ie a tooth or more out on the belt as that will bring up a cam sensor fault too.

if the cam is a tooth out it MAY explain the excessive steam you were getting back in the cold..

so

1) check the cambelt for timing and condition 1st so no further damage is possibly caused.. simple job

2) if the belt/timing is good check out the relay, if you are handy with a soldering iron its an easy job to repair

3) if still no comms it maybe worth removing the ecu from its hidy hole and checking the wiring connections for water ingress and the earth wires by the battery for corrosion..

4) i'll give take a risk and give ya £100 for the car if you deliver it to me

Thanks for all this info, I will mention this to the garage tomorrow. thanks again.

westallc, westallc, wastellc, wastllec, castlwal that's who you need to talk to.......................or something like that.

When I had the same symptoms on my 1.6 - random cutting out getting progressively more frequent, then one day it just started cutting out/revving like mad so I had to get it towed - the garage diagnosed it as the crank position sensor, which they replaced for...er...£1xx (can't remember the exact amount, but that was main dealer price). Cured the problem.

Bit weird with the ECU being incommunicado though...

Rob.

i think the ecu comms is the main bit here really, maybe wet in the connections?

did the abs or airbag have an "enging no communication" type fault stored at all

i think the ecu comms is the main bit here really, maybe wet in the connections?

did the abs or airbag have an "enging no communication" type fault stored at all

No Mate the abs and airbag systems were ok to communicate with and both did not have any errors stored, its just the ecu is not wanting to speak. Thanks.

Well after days of tearing my hair out the garage found the problem... Bloody water ingress getting into the ecu connections they said the cables were green and had to be re soldered there was also broken wires behind the ecu diagnostic socket.

They have got it going again, and said this is prob why it was cutting out as the connections were just making the right contact then when it couldnt get going again the wires were shot.

Water yet again. Least its going again.

oh well at least it right now then mate, did it take them long to find it?

oh well at least it right now then mate, did it take them long to find it?

3 days it took in the garage