03 100HP TDI Passat - Power Loss

Morkin

Folks,

All input appreciated.

On a drive home from Kerry to Dublin on Sunday. Stopped in Limerick and on restart the car had no power, took ages to rev. and miniutes to get to ~60mph.

Continued like this for ~10 mins when going through Birdhill I left it in second and at about 3000rpm the power (turbo) kicked back in and the car was fine for the rest of the trip back (120kph no prob on M7 etc.).

Started it yesterday and it exhibited the same behaviour. I again waited for revs to increase and again around 3000rpm the power came back on and stayed on until I stopped. It went again on restart.

I've surfed and rang around and a common problem on the old 90HP 1.9 engines is the air flow meter malfunctioning. This may be my case as well. Booked in for a check up tomorrow if it will make it to garage.

Anyone shed some light or have similar problems? I hope it's not the turbo unit as thats 1000 to 1500 yoyos.

Thanks in advance,

M.

crosstownk

The Air Flow Meter in VWs does have a habit going faulty. If it is at fault you will have to replace it. A VW one will be over €300 but you can get a spurious one for about €100 or so.

gibbon75

Check for airleaks around the hoses and intercooler,jubilee clips etc.

maidhc

In a slightly related problem my grandfather is having a problem with his 06 Passat PD 105 belching out black smoke between 1st and 2nd gear. It is perfect all the rest of the time, but between the gear change it is like a smokescreen out the back.


It drives perfectly otherwise, although he says it stalls very easily, I havn't noticed any time I have driven it.

ando

original posters problem sounds like faulty mass airflow sensor

Morkin

Thanks for all the replies so far.

Ando - don't suppose I'll be able to just get the sensor replaced rather than the whole MAFM unit?

Any opinions on whether it's worth the extra dosh for a Bosch MAFM versus a generic unit?

Cheers,

M.

BTW maidhc is your grandfather takling his foot of the accelerator when changing from 1st to 2nd?

alias no.9

That doesn't sound like the MAF issue. The way you describe the issue, it's either faulty or not. With the MAF issue the engine would just seem lethargic, you wouldn't have the on/off effect.

Now for the science(ish) bit...
The MAF works by applying a current across each of two wires with high electrical resistances, one exposed to the ariflow in the intake and one shielded from it. The temperatures of the wires are measured and fed back to a control unit. The airflow on the exposed wire has the effect of cooling it. The control unit increases the current in the exposed wire to keep it's temperature equal to that of the shielded wire. The greater the airflow, the greater the cooling effect, the greater the difference in current between the two wires. It is this difference in current which is fed into the ECU as the Air Flow measurement. The more air flow into the cylinders, the more fuel is injected. In VAG TDi engines, you tend to get gunk building up on the exposed wire, reducing the cooling effect of the airflow, making the ECU think there is less air getting into the cylinders so that it reduces the amount of fuel injected resulting in power loss. It's characterised by a gradual loss of power, probably over a number of months. The quickest way to self diagnose the MAF is to unplug it and see if that makes any difference. To find the MAF, look along the air intake ducting between the filter box and the head, there'll be a cable going into a connector, this is the MAF, unplug it and take the car for a spin. Performance should be much improved if the MAF is faulty. Replacement is easy, you just need a set of torx bits and a driver, unscrew two torx head screws and swap it out for the new one. Apparently Pierberg, who supply MAF's to mercedes, make a MAF that will swap with the bosch sourced VW one, which is cheaper and more reliable.

maidhc

Morkin wrote:

BTW maidhc is your grandfather takling his foot of the accelerator when changing from 1st to 2nd?

Yup, its a strange one. Under warranty anyway, although my bet is they will say "the computer says everything is ok".

I wonder if there is something blocking the air flow into your car..e.g. a dead bird, or a bit of air filter.

Morkin

Cheers alias,

If it's not the MAF have you any idea as to what it might be? I've a Hayes Manual for the Passat/A4 prior to 2001, would this be suitable for the 03 model (90BHP versus 100BHP engine?).

maidhc: I guess something could be blocking the intake but it blocks/unblocks repeatably when I'd have thought it's block and unblock only once. Also the power loss started after the car had been parked in a carpark for an hour - and with the front up against a wall! Weird.

VW dealer suggested the turbo hose may be loose but if tht's the case then I'd expect power loss at higher revs, I appear top have the opposite.

Is it possible to do an EMU reset? I mean can a garage do it as say step one in a diagnostic routine as I'd rather not put in a new MAFM and discover it has no effect.

Thanks again,

M.

alias no.9

You can check the MAF yourself by just disconnecting it, you just have to pull the plug out. The ECU will run on default settings, not optimised for economy, emissions or performance, but should be significantly better than with a dodgy MAF.
I'm not sure what else it could be. Is there an engine management light illuminated in the dash? The ECU will have a limp home mode which will allow it to be driven home, but with restricted power if there is a fault. If there was an intermittant fault triggering the ECU to go into limp home mode, it would explain what you're experiencing. You really need to get this hooked up to a diagnostic machine.

Morkin

Thanks again alias,

There's no indication on the dash of any problems. Hope the ECU logs info. that doesn't trigger a warning lamp.

I'll try disconnecting MAF when I get home and the car is due to be checked tomorrow. I'll keep the thread updated.

Cheers,

M.

Sizzler

Bollix..just bought a 2003 passat 130bhp...dont wanna be reading problems about them

I will associate with the poster who said they found them to stall though, I found that with mine but thats mainly down to the fact that you need to give them plenty of welly and get off the clutch. I had been driving a petrol car previously and theres a serious difference in what you can get away with on the clutch and accelerator.

Big Nelly

Sizzler wrote:

Bollix..just bought a 2003 passat 130bhp...dont wanna be reading problems about them

I will associate with the poster who said they found them to stall though, I found that with mine but thats mainly down to the fact that you need to give them plenty of welly and get off the clutch. I had been driving a petrol car previously and theres a serious difference in what you can get away with on the clutch and accelerator.

Ahh petrol heads, had the same problem last year when I moved from a Petrol to the 90Bhp Passat, for the first few weeks at traffic lights etc would forget that I was in a diesel and wouldnt put on enought rev and then chuck chuck bang. Would cut her out. Soon learned the lessons when a few people behind me would start beeping like mad at traffic lights.

Just swapped the 90Bhp one for a 130Bhp one and you need to put less revs on the 130Bhp but still need to give it that little bit of extra that you wouldnt have to on a petrol. Love the 130 thou, power compared to the 90Bhp is great. Any pics of your 03 man?????

tigerman

Hi Guys & Girls,

The Pump Deuce engine was launched Jan 2001 in Ireland, This engine is very easy to stall, Theres nothing wrong with the engine because every passat does it, This is normal so dont worry.

As regardss to teh grandfather, these are active diesels with smal turbos, The reason why it pumps out smoke is that he probably doesnt drive the engine reasnobly enough to vacate the soot from the engine to the atmosphere and the soot stays in the exhaust,

when you blpi the accelerator ie 1st or 2nd then is causes a turbulence in the exhaust and it is probably just blowing the soot from the silencers,

The smoke will not be coming from the engine at this time,

If you let diesels idle for a long time of drive in a grand fatherly way then its just building up in there.

As for loosing power, you cannot get Maf sensors for 2002- passat.

You will have to buy genuine.

Pm me if you need more info.

I have my own computer and do know what i am talking about, i dont repeat what others say, they repeat what i say.

Dcully

Any pics of your 03 man?????

Heres my baby,just popped out to take these for you

Big Nelly

No Alloys? strange. I had enough of Irish models and bought an import with heated seats, cruise control etc. Pics here:

http://www.carzone.ie/usedcars/index.cfm?fuseaction=car&carID=363095

Dcully

Mine is an English import also,comfortline,heated seats etc etc,50k on clock even has that new car smell inside lovely machine dont ask why theres no alloys tbh.
Maybe the dealer liked them and nicked them

Big Nelly

Efioanaes wrote:

Mine is an English import also,comfortline,heated seats etc etc,50k on clock even has that new car smell inside lovely machine dont ask why theres no alloys tbh.
Maybe the dealer liked them and nicked them

Nice, think your dealer did rob them. Every english import I looked at across the range had alloys as standard. Even the 100Bhp models. New car smell in mine till I let a few smelly ones out so need the air conditioning on now:D

Dcully

Hmm im tempted to pick up a set of alloys tbh,some look really well on Passats.
I especially like the actual VW ones themselves,me goes off looking for some.
Not going near a VW dealer tbh,robbing fooktards the lot of them.

Big Nelly

Efioanaes wrote:

Hmm im tempted to pick up a set of alloys tbh,some look really well on Passats.
I especially like the actual VW ones themselves,me goes off looking for some.
Not going near a VW dealer tbh,robbing fooktards the lot of them.

Alloys are nice on mine, nothing special but really the Passats need them, dont bother with VW dealer. I priced for my last one off Bradys in Castleknock and they where talking about 700 euro for the set, they where the basic ones as well

maidhc

tigerman wrote:

The Pump Deuce engine was launched Jan 2001 in Ireland, This engine is very easy to stall, Theres nothing wrong with the engine because every passat does it, This is normal so dont worry.

Probably, most diesels stall very easily now. It seems though that the PD 105 is definately worse for stalling than the PD 100 in his previous car.

tigerman wrote:

As regardss to teh grandfather, these are active diesels with smal turbos, The reason why it pumps out smoke is that he probably doesnt drive the engine reasnobly enough to vacate the soot from the engine to the atmosphere and the soot stays in the exhaust,

No, he drives on as fast as I do to be honest, and he does ~35k kms a year; it isnt a case of going to mass once a week. It is definately a problem. somewhere,

Morkin

Got the car fixed this morning. Faulty sensor on the AMMU (Air Mass Meter Unit).

200 yoyos all in. Common problem from Mercs to Skodas. Back in action now.

Apparently there's a guy in Navan that reconditions the sensors.

Also had to use a vice grips to get the screws holding the sensor out - weird 5 prong star shape with a dome in the middle (the screw heads I mean)

Thanks for all the info folks. I'll be able to change this myself the next time

M.

Sizzler

Big Nelly wrote:

Ahh petrol heads, had the same problem last year when I moved from a Petrol to the 90Bhp Passat, for the first few weeks at traffic lights etc would forget that I was in a diesel and wouldnt put on enought rev and then chuck chuck bang. Would cut her out. Soon learned the lessons when a few people behind me would start beeping like mad at traffic lights.

Just swapped the 90Bhp one for a 130Bhp one and you need to put less revs on the 130Bhp but still need to give it that little bit of extra that you wouldnt have to on a petrol. Love the 130 thou, power compared to the 90Bhp is great. Any pics of your 03 man?????

No pics dude :-( Only have her a few weeks. Very happy with her, a class car. Such a difference from last car (Primera). Ive got my act together as regards giving her welly at the lights anyway, was abit embarassing a few wks ago when I met my mate at the lights and he shot off and I stalled her lol.

Mine is similar to the pics of the other guys but mine has alloys

What are people getting out of theirs on mpg? I reckoned I got 39mpg on mine on the last tank and that was ALL city driving and I was prob a bit thrifty with the gas too when I got a chance

Big Nelly

Sizzler wrote:

No pics dude :-( Only have her a few weeks. Very happy with her, a class car. Such a difference from last car (Primera). Ive got my act together as regards giving her welly at the lights anyway, was abit embarassing a few wks ago when I met my mate at the lights and he shot off and I stalled her lol.

Mine is similar to the pics of the other guys but mine has alloys

What are people getting out of theirs on mpg? I reckoned I got 39mpg on mine on the last tank and that was ALL city driving and I was prob a bit thrifty with the gas too when I got a chance

Well during the week city driving and on the 130Bhp she seems a little bit harder on the juice than the 90Bhp, prob got to do with me flooring it every so often to check out the extra power:D , the on board computer will go from as low as 20 to about 42Mpg which isnt too bad I suppose.

Really you need to bring it on open road, I drove to Cavan from Dublin without cruise control and it sat about 45 for the majority of the trip. On way back up used Cruise control and she stayed at 55Mpg the whole way. This week went to Dundalk on the M1 and had cruise control on the whole way with it bang on 120Kmph and it got up to about 60Mpg for most of the journey:D

Oh yeah my last car before the 90Bhp one was a Primera, you copying me? haha

Sizzler

Cruise Control...on board computer? Ehhh you must have a better spec than me Unless Im seriously missing something !! I have a comfortline and although it has LOTS of extras I dont think I have either of those?! I do have EPS though...is that any use?

If I ever get 45mpg I'll be VERY happy camper;)

crosstownk

tigerman wrote:

The Pump Deuce engine was launched Jan 2001 in Ireland

It's a great engine - I've one in a 2003 Passat TDI Auto - What a macine to drive!!

BTW tigerman it's Pumpe Düse (German) and it's on the way out....

http://forums.tdiclub.com/showthread.php?t=119737

Big Nelly

Sizzler wrote:

Cruise Control...on board computer? Ehhh you must have a better spec than me Unless Im seriously missing something !! I have a comfortline and although it has LOTS of extras I dont think I have either of those?! I do have EPS though...is that any use?

If I ever get 45mpg I'll be VERY happy camper;)

Is yours a Ireland model? if so you wont have half the extra's. Cruise control, EPS, heated seats etc all standard on mine:D

Sizzler

Big Nelly wrote:

Is yours a Ireland model? if so you wont have half the extra's. Cruise control, EPS, heated seats etc all standard on mine:D

It is an Irish car yeah...has EPS, heated windscreen, but no heated seats!

AMurphy

Morkin wrote:

Got the car fixed this morning. Faulty sensor on the AMMU (Air Mass Meter Unit).

200 yoyos all in. Common problem from Mercs to Skodas. Back in action now.

Apparently there's a guy in Navan that reconditions the sensors.

Also had to use a vice grips to get the screws holding the sensor out - weird 5 prong star shape with a dome in the middle (the screw heads I mean)

Thanks for all the info folks. I'll be able to change this myself the next time

M.

I cannot see how these sensors can be reconditioned or repaired, they use a thin-film sensor element, May be able to do something with the electronics immediately behind it, and given these are usually encased in potting compounds, I doube even that, but not the sensor element.
I'm assuming you have the sensor that pokes into the airstream like a finger, with a small passageway through it.

5 or 6 prong star. There are anti-tamper Torex screws, but Torx is 6 sided.
Maybe they use 5 to insure you take the item to the a dealer who are the only ones to have the special 5-star screwdriver.