A3 1.8T Occasionally running like a bag of hammers??? HELP!!

[Andydos]

Hello all!
I bought a 2000 reg Audi A3 sport 1.8T with 66k on the clock about 2 months ago. I’ve seen loads of threads about engine problems but can't seem to find one that matches my problem exactly so was wondering if I describe the problem will/can someone offer some advice in this matter?
Some days the car is faultless and runs perfectly but annoyingly other days the revs jump up and down when idling and when I drive approaching traffic lights etc in neutral the revs sometimes dip so low the engine cuts out. Also when it is playing up, during acceleration, there is a marked lack of power (feels like safe mode but turbo is still spinning and no engine management light on). My brother works in a garage and did a diagnostic on the car which revealed the following fault:

17608 P1200, RECIRCULATING VALVE FOR TURBOCHARGER - N249: Mechanical Malfunction.


As far as I’m aware, the car is 100% standard. a friend of mine had an octavia VRS and has driven my car saying it performs the same as his so I don’t suspect its had a remap or anything. I also removed coil packs 1 and 2 and they same new and they don’t come up during diagnostic so im thinking it cant be them?? Would I also be correct in thinking it cant be a torn diaphragm in the DV as if it was, the problem would be constant?
The garage fitted a new N249 Valve but the fault comes up again after a few minutes of the engine running. Does anybody think the sporadic problem that im having with my car is to do with this fault or could it be anything??? My brother said I can bring the car back but they don’t really have alot of experience with VAG engines so suggested that rather than them just changing a load of parts with possibly no result, I take my car to a VAG specialist who may know exactly what is causing this. The annoying thing is that it is not a permanent problem, it runs fine 1 week then badly the next? But before I take it to a VAG garage thought I would put this thread out and see what happens. It’s a great shame as other than that its a great car!
Any advice would be appreciated!! Cheers

 

[S3 HODGE]

I had a simular problem with my old A3. If i can remember when i changed something it stopped doing it.....Sounds strange but, It may of been something to do with my Thermostat/coolant sensor or something simular if i can remember.

 

[pauldazzle]

Coolant temp sensor. If you have the old type black one change it for the later revised green type. Throttle body might need cleaning too.

 

[pauldazzle]

As for the 17608 code I would change the stock DV first as it's notorious for failing.
Forge 007p is the most popular replacement.

 

[reptor245]

I would change the stock DV first as it's notorious for failing.
Forge 007p is the most popular replacement.

How do you no if the DV is failing? i sometimes get poor acceleration from time to time, No fault codes come up and the turbo spins up fine. i mean the boost seems abit flat. probably about 5% of the time.

 

[pauldazzle]

Ok you need to remove the DV, push the piston up, put your finger over the small nozzle on the top of the DV, & then release the piston, it shouldn't drop down untill you remove your finger off the top.

 

[Andydos]

Coolant temp sensor. If you have the old type black one change it for the later revised green type. Throttle body might need cleaning too.

Thank for that, I suppose it wont hurt to try changing that. Is the best place to get the green type from the main dealer? And if so do I just ask for 'the revised green coolant temp sensor?

 

[pauldazzle]

I use http://www.thetradepartsspecialists.co.uk
Genuine VAG parts, but cheaper than main dealer. The black ones aren't available anymore so you would be supplied with a green one.
Don't buy an imitation off ebay as they're rubbish.

 

[Andydos]

I use http://www.thetradepartsspecialists.co.uk
Genuine VAG parts, but cheaper than main dealer. The black ones aren't available anymore so you would be supplied with a green one.
Don't buy an imitation off ebay as they're rubbish.

Thanks for your help. I will replace the coolant temp sensor and update this thread as it mau be useful to others in the future, (If it sorts the problem out!!)

 

[pj22w]

hi, I have had the same problem with my 2004 1.6 SE for the last 2 months. It started with irregular revving and sometimes stalling then the traction control light started to come and go (mostly on) then the emissions light then the temp gauge stopped working for most of the time and one of the fans keeps whining and seems to be over worked even when I just stop the engine. Disaster I thought!

I'm a pretty much a newbie but borrowed a VAG from a mate and it showed up the error code for coolant sensor to ground. I reset the code but the lights came on a few hours later. I'm going to replace the sensor hopefully next week. Is it a case of unplug the old and plug the new one in? and can anyone tell me where to find it?

quoted £25 from Audi Belfast for the sensor. grr that's after a £500 service 6 months ago. never again. Rogues the lot of them

Many thanks

PJ

 

[Andydos]

hi, I have had the same problem with my 2004 1.6 SE for the last 2 months. It started with irregular revving and sometimes stalling then the traction control light started to come and go (mostly on) then the emissions light then the temp gauge stopped working for most of the time and one of the fans keeps whining and seems to be over worked even when I just stop the engine. Disaster I thought!

I'm a pretty much a newbie but borrowed a VAG from a mate and it showed up the error code for coolant sensor to ground. I reset the code but the lights came on a few hours later. I'm going to replace the sensor hopefully next week. Is it a case of unplug the old and plug the new one in? and can anyone tell me where to find it?

quoted £25 from Audi Belfast for the sensor. grr that's after a £500 service 6 months ago. never again. Rogues the lot of them

Many thanks

PJ

think your problem may be different to mine as I dont have any warning lights playing up. Only error code is for the re-circulating valve for the turbo. I dont know where the sensor is yet as Im only going to look into it when I have the sensor but I would assume there would be a thread somewhere on here for that.