Time to get you all scratching your heads!

[Dibdub1]

Right guys and girls! Recently bought an Audi A3 1.8 T sport, S reg (1998) Drove it all the way home from Essex to manchester. The car didn't miss a single beat all the way home until getting about 5 miles away from home, at which point (after some "spirited driving" and one of the coilovers bottoming out) I heard 3 beeps but due to my DIS not working, didn't have any idea what it had thrown up! Stopped the car immediately, killed the engine due to my worst case scenario fears of it being cracked sump. Looked underneath as thorough as possible and no signs of a new "scrape" to anything underneath so ruled that out. Started it up again, car still drove with boost etc, as I continued to drive home, the car in a way started to enter limp mode by cutting off all boost!

Finally got the car back to my friends house where his brother plugged it into the diagnostics machine and it threw up "camshaft position sensor" we also identified a small split in one of the vacuum hoses (one that goes from under the plenum chamber in the middle to the right hand side of the block where it joins up to the rest of the vacuum hoses) Replaced this hose and cleared the codes. Started the car and it idled spot on, mate took it around the block and returned to say it was still running with no boost and very slow to climb the revs whilst driving.

Plugged it in again and it threw up "camshaft position sensor" again, car was booked in thursday (21st) for cambelt and water pump anyway. Mechanic's been looking at it and eliminating possible faults one by one.

So far we've ruled out camshaft position sensor (replaced with brand new unit and physical positioning checked) it is still throwing up camshaft position sensor! Then tried new Maf sensor, still no boost etc, also tried N75 valve/N249 and none of these have made a difference. The mechanic's checked all boost hoses, there are no boost leaks, the turbo is fine, actuator is also fine however it is still throwing up "camshaft position sensor" as a fault!

Everything he's tried so far (checked pretty much everything and has said it's all spot on and most of these issues would point at turbo, but as said it's fine and fully operational!) So after that, the only thing left that he can think of is the Ecu. I've bought one which he's got at the moment to try, he tried to move across the "soft" files yesterday from the Ecu already in the car (this has had a motech remap) however due to them locking the files after a remap, he couldn't. I rang Motech yesterday to confirm and have been told how my mechanic can try the new Ecu by de-immobilising it and then re-aligning the immobiliser with the one on the car.

Have asked him to try the Map sensor today and also to try swapping the Ecu over.

So now i've ruled out a few things already, I'm curious to see what you guys can maybe think of?

Spec of the car is roughly 150k, THS TIP, Forge relocator kit, 007P, milltek cat-back non res, VR6/G60/Clutch/Flywheel Pipercross panel filter and smoothed airbox.

Sorry to write a huge essay and bore you guys but hope one or two of you might be able to throw some ideas at me. I've not even had the joy of having the car overnight as, as soon as it got home, I left it at my friends to be taken down to the garage on the Thursday!

Thanks a lot in advance for any help/ideas/suggestions!

Cheers,

Josh

Oh and one last thing, what is a Map sensor anyway? And what does it do? haha

 

[DaveA3]

think the map sensor measures the boost after it gets reused but dont quote me on that.

 

[Dibdub1]

Thanks for the response either way mate

 

[Alex C]

i thought the MAP sensor measured boost after the intercoolers but beofre the throttle body

 

[Dibdub1]

Hmm I've no idea lol!

 

[s3dave]

i thought the MAP sensor measured boost after the intercoolers but beofre the throttle body

Correct

 

[gary3306]

I know this might sound daft, but believe me when I say we had a car at work about a year back, limp mode and a 'camshaft position sensor' fault. Like yourself, this was renewed, as were a number of sensors (MAP,MAF). What fixed it instantly was.........................................a new CRANKSHAFT position sensor. Worth a try.

 

[s3dave]

I know this might sound daft, but believe me when I say we had a car at work about a year back, limp mode and a 'camshaft position sensor' fault. Like yourself, this was renewed, as were a number of sensors (MAP,MAF). What fixed it instantly was.........................................a new CRANKSHAFT position sensor. Worth a try.

Interesting..when my crank sensor went, the symptoms were cutting out when warm and failing to start until cooler
Biatch to get to as well!

 

[dannyh]

I know this might sound daft, but believe me when I say we had a car at work about a year back, limp mode and a 'camshaft position sensor' fault. Like yourself, this was renewed, as were a number of sensors (MAP,MAF). What fixed it instantly was.........................................a new CRANKSHAFT position sensor. Worth a try.

as he said tho in his origonal post,

So far we've ruled out camshaft position sensor (replaced with brand new unit and physical positioning checked) it is still throwing up camshaft position sensor!

so it is nothing to do with the sensor

 

[Endacy]

He is sugesting it might be the CRANKshaft sensor not the CAMshaft sensor. As daft as it sounds you never know I guess.

 

[aragorn]

No engine sensor will cause three beeps.

Those beeps are only caused my a small number of critical issues, such as oil pressure, coolant level or temperature, or brake issues. None or which are logged in any ECU.

I'd be putting my money on the oil pressure warning.

As for your camshaft thing, i'd be willing to bet its nothing to do with the ECU. Perhaps a wiring fault, dodgy cam timing, or incorrect pickup wheel are all possible causes.

 

[Dibdub1]

Thanks a lot for all the responses guys! Finally found out what it is! Basically the ecu was right in throwing up camshaft position sensor as the internal cam is out by 2 teeth! I shifted down too early causing the car to over-rev and somethin in the head has disintegrated! something related to the chain in the cylinder head? But yeah, at least it's sorted now!