Jasper37

22 hours ago, cliffcoggin said:

Peter.

Any work done on your car by an Audi garage during its existence will have its history centrally recorded, so it should be possible to find when and by whom the sensor was fitted. If you have had work done to it by a non Audi garage there will be no such record.

Cliff,    I have every receipt for all works and services done on car since new.  No receipt for a new MAF Sensor, can't believe they would fit a new sensor for free LOL

I have found an issue which I find a bit strange, having had my A3 since new, never has it been repaired with a replacement MAF sensor, I have been checking certain areas of car due to occasionally the car goes into limp mode when at high speed {NO ENGINE LIGHT} but give error code P0234 overboost condition. on VAG Com.

Anyway on looking at the MAF as pictures both items ie outer housing and internal sensor are stamped Audi, the number on outer housing is the correct model number for the car however the sensor itself Number F 00C 2G2 055 that is fitted, I am advised it is the incorrect sensor for the car VERY STRANGE?  However the car issues did start just after my car went into my normal garage for an MOT.

Any advice, I am being told by two online parts companies that the sensor doesn't  fit my car. Could this be the cause of the limp modes?  I am presently trying to find out what the correct sensor number is.

Images of my outer housing and sensor itself is attached.

On 6/12/2021 at 3:42 PM, Jasper37 said:

Hi Steve a late reply, however due to a poor Haynes manual, I couldn't find the Boost sensor. However going to your second part of advice, I removed the MAF sensor and gave it a good clean with proper cleaner, next morning took car out took it up to speed which it normally goes into limp mode, engine gave a bit of a stutter close to where it goes limp then ran ok, no more limp mode?  Strange as no errors shown on MAF sensor?

Regards the Boost sensor, having for a copy of the VAG manual, for my A3 it shows a solenoid box with 6 pipes attached and says the boost solenoid is further on the left of solenoid box, whereas removing the fuse box cover will allow better access to booster.

So much for the Haynes manual which also gives directions to the booster from drivers seat. So much for Haynes gone into bin.

However all appears to be running ok.  Many thanks for your advise given.

Further to my last after close to 6 weeks of no limp mode, my car is now going into limp mode again, tried a new MAF off eBay, my car would not run properly so put old one back on. Found Boost sensor have given it a good clean, but car still occasionally goes into limp mode mainly after about an hour running at approx. 70mph. Now back to square one, no idea where the boost solenoid is, I am baffled, only thought is to put in a new boost sensor and try it? any advise mush appreciated.

Hi Geoffrey, if you can send me an email address, I could send you a copy in pdf.

On 4/8/2021 at 6:57 PM, Stevey Y said:

Hi sorry for the late reply, the picture you supplied is indeed a boost sensor, if yours looks like that you are in, either way scrub the dirt off and get the part number then go fishing on eBay plumb in the Audi part number and it will give a good range of choices this way it will be a lot cheaper than the thieving scrotes at Audi or Eurocarparts.

I am pretty sure that this item is plug in and play and won't need coding, I will check, if you have a problem deciphering which number is the part code either post a picture of your cleaned part so I can see the numbers or email me the VIN for your vehicle and I can't the number off of my system, Do not remove the old part until you have a new one as the pipes can be awkward to remove because they are crusty and may need persuading with a bit of hot soapy water

Steve.

Hi Steve a late reply, however due to a poor Haynes manual, I couldn't find the Boost sensor. However going to your second part of advice, I removed the MAF sensor and gave it a good clean with proper cleaner, next morning took car out took it up to speed which it normally goes into limp mode, engine gave a bit of a stutter close to where it goes limp then ran ok, no more limp mode?  Strange as no errors shown on MAF sensor?

Regards the Boost sensor, having for a copy of the VAG manual, for my A3 it shows a solenoid box with 6 pipes attached and says the boost solenoid is further on the left of solenoid box, whereas removing the fuse box cover will allow better access to booster.

So much for the Haynes manual which also gives directions to the booster from drivers seat. So much for Haynes gone into bin.

However all appears to be running ok.  Many thanks for your advise given.

On 4/3/2021 at 12:27 PM, Stevey Y said:

Hi, sorry am I missing the point here, how the hell would the turbine vanes soot up if the car has been idle for months its not like a chain smoker that was sitting in an armchair all through the lockdown.

I think it has more to do with either the MAP/Boost sensor on the intake manifold side or the Oxygen sensor on the exhaust, in view of the age of the car the MAP sensor would be the first port of call as these for a car of your age are relatively cheap, sensors should be changed about every four years regardless of milage as age is the main factor with failure, most sensors are high heat resistant plastic and especially the MAP which has a plastic pressure membrane inside it but even this will degrade over time when it is dealing with hot air and gas and sends an implausible signal to the engine management system which will throw up a light and put it into limp mode.

have never been a fan of aggressive fuel system cleaners as invariably they will loosen dirt in the system which then heads for the injectors, not good, if you use a spray down the air intake cleaner to clean your turbine this heats the fuel up and as it comes into the engine via induction and goes no where near the internals of the injectors and cleans the intended part and nothing else.

Steve.

Hi Steve,

Thanks for your advice, however being a newbie not too sure if I am looking at the correct MAP/Boost sensor on the intake manifold side, as you said in your reply.  I only have an HAYNES manual to go by.

May I ask if the attached picture from the manual is the boost sensor in question white pointer, pointing at it.

Also is it easily accessible to disconnect and remove, to identify the product number to buy a new one to fit. As there appears to be many types or can you recommend one such as Bosch from eucarparts or replace with an Audi one?

Much appreciate if you can advise me on this DIY or would I be better asking a garage to replace it with a new sensor?

Pete

Hi

New battery last year, engine turns over normally, keeps its charge.

 I have an Audi A3 2.0 Tdi 2004 62000miles.

I have read most forums regards issues of overboost/limp modes, however:

First instance was it went into limp mode with orange engine light, on scan error code P0234 Over boost. Turned off engine light and deleted error code.

Garage told me due to car sitting in garage for a few months during Cov-19 isolation, more than likely carbon on vanes and advised to treat fuel with 2 bottles of Forte Advanced diesel treatment to clean system.

However the car runs fine turbo appears ok, until I hit 8o mph, whereas it loses power down to 6o mph and no turbo kicking in, there is no engine warning light and on scan shows no errors.

However on stopping turning engine off then restarting engine all runs fine again until taking it to 80 MPH on the speedo.

I have taken the car to the high revs to red on speedo to just under 80 MPH and it runs ok, occasionally it kicks out some smoke which hopefully is the system getting cleaned. But I cannot understand why the car keeps losing power {{limp mode} but no engine light or error code?

Anyone advise where to start looking at possible reasons, as my garage has also scanned and found nothing, just said keep running it and give it the gun to clean out the system?

Anybody have any advise to what the problem is?