Engine Fault

[msc]

I searched the forum and only found one reference to the symtoms I am experiencing but no solution / reason given. I have just aquired my Galaxy 1.9 TDI PD 116HP 6 speed manual May 2003 (After facelift) 55t miles. I had the fault codes read by our equivalent of AA (I'm living in Austria) and there weren't any. They suggested maybe the airflow mass meter was at fault. The symtom occurs after you lift of the accelerator and slowly depress it again (in any gear or speed). This results in a short hesitation of the engine to pick up (as if it stalls for a split second) which jerks the car and snatches the transmission. This only occurs when the engine is at full operating temperature, i.e. not during warm up. Other than this the engine runs, accelerates and ticks over (approx 9,500 rpm) fine. I also suspected the accelerator sensor but allowing the car to tick over in first on a flat road results in kangerooing as the engine tries to maintain its tick over speed which for me rules out the sensor. Basically it is an exageration of what is experienced at higher speeds e.g. cruising in 4th at about 30 to 35mph on a flat road where you need to occasionaly slightly accelerate and lift off and so on, you get a slight jolt each time you accelerate after you lifted off. Varying the the position of the accelerator pedal does not result in the problem, only after you fully lift off. BTW I am an engineer and eperienced home mechanic, this is not a transmission or turbo lag problem. I would appreciate any help with this annoying problem which spoils an otherwise brilliant car. I am also hesitant to take it to the dealers based on previous bad experiences, also parts prices are more than double UK's. German and Swedish didn't list the airflow mass meter for the 2003 Galaxy, any hints in the parts direction are also welcome.

 

Thanks

[seatkid]

Possibly a loose bottom crankshaft pulley causing shift in timing.

[msc]

Thanks, I'm not able to check this at the moment, but if this were the case I would expect this problem to occur when blipping the engine or when the engine is cold but it doesn't.

I'm new to the TDI world so all these electronic sensors etc. make life difficult without a personal reader.

I made some more observations on the way home. This hicup of the engine doesn't happen every time you lift off and accelerate or when changing up the gears. It seems to come in phases and is more pronounced at low revs, 1500 or so. Also it only happens after the overun e.g. under engine braking and then accelerating, but as mentioned before not everytime. Sometimes it will stotter once and sometimes twice before taking up the acceleration. Could this be related to a vacuum issue?

Just to add missing info, the engine type is AUY, it has a full dealer service history (for what that's worth), the last one 1000KM ago, also it had the cam belt done at 60t KM. A correction to the idle speed as I read the dial wrong, it idles steadilly at 850 to 900 rpm warm or cold.

Elsewhere on the forum I read about drive shaft problems, mine had the RHS stub axle and drive shaft replaced at 75t KM allong with the front discs but these are well worn and look original to me.

A link on this forum suggested looking at the tdi owners site, they mention the possibility of cleaning the MAF, anyone had any success with that? I checked the contact to the MAF, its fine and no corrosion or water ingress.

 

Also does anyone know where I can download a workshop manual?

 

Thanks

[mumof4]

download a workshop manual...Hmm......you can buy a TIS disc from ebay?????..or there is ETKA..

If you do get a disc..make sure you get the right one as there a couple of diff ones out there.There is no Haynes Manual for the MKII Galaxy which is what you have.All we have are the discs.

[Smilge]

Other than this the engine runs, accelerates and ticks over (approx 9,500 rpm) fine Jeez ...... I'm surprised its running at all msc!!! ;) I'm sure you mean 950 RPM ...... right back to the problem. From my own experience from other cars this sounds like part of the "anti run on" system (someone may be able to confirm this) or from recent experience either the turbo Boost control solenoid which controls the VNT mechanism to adjust the pitch on the turbo vanes. Its common for the VNT mechanism to stick and there are plenty of posts on here to give you some pointers. Hope this helps

 

Chris

[msc]

Thanks mumof4, couldn't reply till now as I'm off sick which started when I started this thread, my excuse for boobing on the RPM figure (Chris) ;-) , actually I was serious about the download possibility (free of course). I haven't had a really good scout round yet. There are some nice people who put them on their websites and some who burn them on CD and sell on ebay. I have a link to a Russian site who have most popular Japanese bikes up there, original copies of factory workshop manuals. Not sure if I'm allowed to post the link here but I guess members who might want to avail themselves of the info could drop me an email, I remember activating that bit somewhere to be displayed.

There are also alternatives to Haynes to buy if you are comfortable with German. I haven't looked for the Galaxy yet, but have bought one for my A-class via Amazon Germany, the titles go under "Jetzt helfe ich mir selbst" (now I'll fix it myself) by Dieter Korp. It has some useful stuff in it and good pics, but avoids the difficult things like an engine strip. Another one is Verlag Bucheli. The one for my old veedub type 3 doesn't have pictures of the strip down and the authors hands but it covers practically everything in detail.

A colleague of mine has one for a Sharan and has just sold the car, maybe I can tap him up for that before he moves to Germany. He's dad of five! They replaced the Sharan with a T5 bus. ;-)

 

So now back to my original problem.

Chris, I did read the articles on the solenoid actuator sticking problem on this forum and the tdi owners forum. In my opinion this would result in poor performance, or uneven acceleration as the boost pressure wouldn't match the said revs. I will squirt some oil on it when I finally get that silly plastic cover off.

I like the idea about the anti runon kicking in and out suggestion because this would produce a similar result. However this circuit is linked to the ignition key position (I think) and should only come in when you turn the engine off. If this were faulty wouldn't it happen on other occasions other than after the throttle off which I'm experiencing? Or maybe the central management computer has got itself mixed up.

 

Now for more info and corrections.

Finally I forced myself to go to the docs yesterday, I originally thought I had a summer flu (common over here, like a normal flu but without the runny nose), then my wife noticed some spots round my waist and sure enough the doc confirmed shingles, so that's me out for a couple of weeks. I didn't know that its like having a megga hangover and that since Tuesday :-(

Well all this is relevant as the docs are in the oposite direction to the normal way to work and starting off with a long downhill and 30 kmh speed limit. Try provoking the stotter again and sure enough it was there repeatedly, engine cold!

 

So whilst resting in bed the old grey cells came up with a theory. This happens after lifting off with the engine braking, also it seems to happen when you have lifted off for a longer time before you accelerate again especially at low revs. So is the following theory possible? Could there be a loss of fuel / pressure, leak through / leak back in one or more of the injectors on the overun mode (where fuel supply is cut) such that when you put your foot on the accelerator again it sends the signal to squirt and there's nothing to squirt or too little untill the system gets up to pressure and sorts itself out.

This is assuming that our AA guy messed up the readings as I would expect this to show up in a fault code. I have a reason for suspecting this as he thought his tester wasn't working, they had a SW problem / upgrade the day before but his colleagues said it was. His first attempt brought nothing as he had selected the wrong engine or something. The second attempt worked and listed out each step from engine to ESP, Klima, ABS, Airbags etc. but no errors. He said a dicky MAF wouldn't register an error code, is this true?

 

So that's where I'm at and although at home am not able to work on it.

 

I have a few more unrelated questions not having a manual to refer to so I will start a new thread for those.

[turk90210]

well for what its worth I would get a copy of vag.com and a lead and do a scan with that, the problem with generic obd2 scanners is that they wont always pick up the fault codes, Ive done the same with mine. my generic had all the airbags,transmission ect but showed no faults, I obtained vag.com and a lead and did a scan and got 4 faults

with the same software you can track the actual and requested reading of the maf to find out if its related to a faulty unit aswell as it wont show up as a fault code unless the wires are disconnected some how

[msc]

Yes I suspect you may be right.

Gone are the days of listening down the carb venturis with a piece of rubber pipe to ballance them on my midget. If you haven't got the right tools you're stuck nowadays.

Any good tips where to get this SW and cable from?

Maybe a silly question but are these readout cables standard across many manufacturers or do they all have their own type?

 

Thanks

[turk90210]

obd II as it is known is a standard with all manufacturers after 2001/petrol 2005 /diesel engines and certain pins on the diagnostic plug have to be the same for all to allow the powers that be if needed to check up on emissions ect it is through the same pins that the generic obdII scanners use but it can only tell you a limited amount of information ie certain engine related problems.

The dedicated software if affordable is the better way to go if you want to go deeper and for the diesel galaxy that would commonly be vag.com as it is basically a vdub with a ford badge

the software can be d/loaded from www.ross-tech.com on a try first to see if it can connect before registering, they also do the leads but the expence is your choice

however 3rd party leads can be bought from ebay but will only work with version 409 vag.com(serial connection) so it allows for a cheaper alternative but can be a bit flake in connecting

best thing to do would be to read up on it, have a look at the web site or just stick in a search for vag.com then make your mind up from there

[msc]

OK FIXED IT!!!!!

It was the b....y MAF! After more reading and searching and thinking I had nothing to lose I decided to take the MAF off and have a look. A question from a member on the TDI site gave me a hint, asking if it could be cleaned. Answer was maybe but don't touch the element with anything.

Well got those daft screws out and promptly made a hacksaw cut for a flat blade screwdriver for refitting and possible future removal. The hint was to wash it in white spirit, well I used petrol hoping that bosch used quality plastics which wouldn't go brittle. The heating element which sits recessed in the airflow was a bit dull (tarnished) but looked OK. The metal element looked quite stable so I decided to wash it with petrol, this didn't remove the dullness. I then filled the recess with petrol and gave it a light scrub with a 1/4 inch paintbrush which was stiff enough and fitted in the recess. The element then came up shiny. I still wasn't hopefull but thought if this gave a marginal improvement it could be a pointer for me.

Well about an hours job (mainly because of those screws) and it was all back together.

Next day drove to the docs and no stotter. Still touching large lumps of wood the following day I drove to work, no hesitation, stotter, kangarooing whatsoever. It completely transfomed the car and I am still astonished how such a light covering could have such a dramatic effect.

 

So for all those who have similar symptoms as I had (remeber it only gave a stotter after lifting off and slowly acelerating again) then try cleaning the MAF.

 

Other jobs just completed include fitting a Bosal towbar in 1 day, (4 hours working out how to get the bumper off, no manual and finding the reversing light / fog light cables, they change colour at the connectors so the main loom isn't as in the fitting instructions).

 

Fixing the clang of the drivers door shutting with window down. Thanks to the article about door pad removal, I would never have found those 3 hidden bolts or getting the grip off. I'm familiar with removing these but never came accross such tight clips, I lost half the points on 4 out of the 9 and one lower bracket which the clip fits into.

I read someone on another thread had similar noises. I guessed at a loose lower window guide and was right but that wasn't all, the front glass clamp was loose and the rubber pad had split and fallen into the bottom. Recovered that and refitted it. The clang is still there but less so, not the thud you expect and get with the window up or that of the passenger door with the window down. I couldn't find anything else hitting the glass etc. so it will stay like this for now.

The pics on the door pad removal were helpfull, one which would also help would be a picture of the back so you see exactly where all those clips are which would help in knowing where to go in with the screwdrivers etc. I was in a rush and it went dark otherwise I would have taken a picture. Maybe next time when I waxoil the car and inside the doors.

 

TIS disc on its way. Now got a German manual (a bit limited on the PD engine though) from my colleague who sold his Sharan. Not sure which way to go with the VAG-COM SW and lead.

 

Thanks to all for the suggestions and tips on this one and I hope this thread may help someone else.

 

Steven

[BigDog]

Hello Steven, I have the exact same symptoms with my 2003 Alhambra TDI 115 PD with AUY engine at 130,000 miles. The only difference is that sometimes when idling it will misfire, a single stumble and then recover, usually with a chuff of smoke out of the exhaust. I will try cleaning the MAF like you suggest.

All the best, Matt

[BigDog]

Got up early, cleaned MAF with carb cleaner, reassembled, took it for a spin - and it is completely fixed! No more stumbling, hesitation, stalling, or kangaroo behaviour in slow moving traffic. Many thanks for the guidance. All the best, :rolleyes: Matt