Lack of power from my 1.9TDI Passat

[andyccna]

Hi Everyone, I found this forum a couple of weeks ago whilst searching for answers to my power loss problem on my 2000 1.9TDI Passat. I have looked at all the things suggested on the various threads and none have worked in my case. The car is just generally lacking power, almost as though it had no turbo. I have had the turbo checked by an indipendent turbo specialist and he says it is working fine. I have changed the MAF and this caused the car to behave rather strange, producing jurking motions and clouds of black smoke. When I replaced the original MAF we where back to square one. This is not an intermittent problem but does seem to have come on gradually over a period of several months. Any Ideas out there??? :1zhelp:

Andyccna

[hartfell]

hello,i think i,ve got similer problem to you,i can drive about 1 mile then lose turbo,but if i turn off ignition then restart the turbo works fine for anything between 1 mile and 12 miles then lose it again,i was told that the turbo had clogged up and to try hitting it with a piece of wood,which i tried,and if it did,nt work would need a new turbo, but i think its an engine management problem,i,m also looking for a soloution,Ian.

[onzarob]

hello,i think i,ve got similer problem to you,i can drive about 1 mile then lose turbo,but if i turn off ignition then restart the turbo works fine for anything between 1 mile and 12 miles then lose it again,i was told that the turbo had clogged up and to try hitting it with a piece of wood,which i tried,and if it did,nt work would need a new turbo, but i think its an engine management problem,i,m also looking for a soloution,Ian.

Try disconnecting the MAF sensor and see if the same happens, I did this to diagnose mine.

Rob

[greas-E-monkey]

Hi there do not disconnect the air mass meter as a means of determining wether or not it is faulty, What will actually happen is that a fault will be registered in the ECU and the vehicle will run in a limp home mode until this is reset. There will be a huge loss of power. The only way to accurately check an air mass meter is to take it to a VW agent and have the MVB's checked against the values published in ELSA.
Dont waste any more time, A VW dealer is what you need:biglaugh:

[p-torque.co.uk]

You can easily check air flow by using VAG-Com

Just use the measuring blocks in the engine module:beerchug:

[onzarob]

Hi there do not disconnect the air mass meter as a means of determining wether or not it is faulty, What will actually happen is that a fault will be registered in the ECU and the vehicle will run in a limp home mode until this is reset. There will be a huge loss of power. The only way to accurately check an air mass meter is to take it to a VW agent and have the MVB's checked against the values published in ELSA.
Dont waste any more time, A VW dealer is what you need:biglaugh:

That's not quite true, there was no fault regisitered on my 1999 a4 TDI, I do have VAG-Com to check. If you read around the only way to diagnose the MAF is by airflow readings, which you point out. I ran my car for two weeks with the MAF unplugged and as soon as the new one was installed to engine was back to full power. It ran better in Limp mode than with the old MAF connected, hence trying it disconnected.

I would suggest that the owners are asking a quick solution as they don't want to pay high garage prices to fix a simple fault. Just hold on a minute before ridiculing owners who want to to fix there own cars.

A better suggestion would be to advise the owner to get the free version of vag-com and an inexpesive cable (£30) and take the MAF readings as I did. Still allot less outlay than taking it to a garage and the pleasure of fixing your own car.

One last note you can get a MAF for £45 allot less than an hours labour in a main dealer.

Rob :D

[p-torque.co.uk]

That's not quite true, there was no fault regisitered on my 1999 a4 TDI, I do have VAG-Com to check. If you read around the only way to diagnose the MAF is by airflow readings, which you point out. I ran my car for two weeks with the MAF unplugged and as soon as the new one was installed to engine was back to full power. It ran better in Limp mode than with the old MAF connected, hence trying it disconnected.

I would suggest that the owners are asking a quick solution as they don't want to pay high garage prices to fix a simple fault. Just hold on a minute before ridiculing owners who want to to fix there own cars.

A better suggestion would be to advise the owner to get the free version of vag-com and an inexpesive cable (£30) and take the MAF readings as I did. Still allot less outlay than taking it to a garage and the pleasure of fixing your own car.

One last note you can get a MAF for £45 allot less than an hours labour in a main dealer.

Rob :D

Have to agree with Rob here.

You can unplug your MAF to test.

If it runs the same, or better, its new MAF time.

[onzarob]

That's not quite true, there was no fault regisitered on my 1999 a4 TDI

I've got to eat a little humble pie here, I have just check my car with VAG-Com today and there is fault registered for the MAF, open/closed circuit intermitant. This was probably due to when i disconnected it and installed a new one.

The important point is that is does log a code, but no MIL Light and as soon as the new MAF was fitted all came back to normal. This was on a 1999 Audi A4. It may be different for other years,

I cleared my fault by using a cable from ebay and the shareware version of VAG-com. look at www.ross-tech.com (http://www.ross-tech.com) for info.

Rob

[greas-E-monkey]

Hello again, the forum adminstrator states: Please note: It is recommended by the site administration, to have your vehicle checked by a qualified VAG technicion BEFORE following any technical advise offered on VWAudi Forum. Unless stated otherwise, NON of us are qualified technical specialist;)

I am qualified to give technical information on VW's as I am a main dealer Volkswagen technician. The data/values given in the MVBs on VAG COM are useful but only if you understand them and can translate them into a useful means of diagnoses. Failure of airmass meters bring up faults and sometimes they do not ( just lack of performance or economy).
By using a main dealer to diagnose your vehicle you take some of the risk away ie if they get it wrong they should remedy it without further cost to you. If you guess at an airmass and then its wrong then you guess at a coolant temperature sender, then you guess at a.... you get the picture!

fixing your own car gives great satisfaction and saving money is great too but cars get more advanced and most people dont have access to VAG computers.
its your money so its up to you.
I have had my little rant, peace.

[onzarob]

I agree with you on the best place to get it fixed is at the main dealer or trained local specialist.

I just like to confirm my suspsions on the fault first and if i can fix it myself all the better. I allways err on the side of caution and trust trained professionals like yourself to rectify the problem. I work in IT and its the same there as little knowledge can be more harmful than good.

With my car it was showing clssic signs and I thought i would give it a go, if i had been unlucky andthe problem stayed, i would have probley gone to garage than buy one part after another and waste valuble time.

Good we know we have a profesinal keeping us on the straight and narrow and not slipping into wild urban myths when fixing and diagnosing problems.

Cheers

Rob :D

[adamss24]

Hi, where you got the replacement MAF from ? Get a genuine one not a cheap one from Euro Car Parts as they are prone to be faulty. Also, its wise to disconect the battery to let the ecu learn the new settings for the new maf and give the car somme load as well: motorway, somme hills and traffic. Also, you could check your intake manifold for clogging as the ECU thinks a lot of air is getting into the engine and tries to feed more diesel to keep up. Also about the Vag techs, just get yourself a ELSA WIN/ workshop manual and a Vag-com cable from ebay + a registered Vag Com software and you are all set. You will have the same tools as the dealer have and trust me, i am talking from my own experience. I do all my services/TB, love to get my hands dirty and intimate with my car and do not have to pay labour costs at90 pound per hour. I have seen many back yard mechanics with more knowledge than many audi techs ! I do not mean to be sarcastic but that is a fact. If i need special tools or equipment then yes, i will take my car into a garage, until then i will do wathever i can to know my car ! Thank you.

[Jbond4321]

Im going to try it on my Sharan today as doing 120miles up the M6 doing nearly 60 is a nightmare.

So just unplug it and drive it ? And if it drives the same it could well be the MAF sensor?

Im going to try and get it to local garage and get it hooked up in the mean time.

Cheers


Matt