Turbo Problems (Revs)

[Padwick]

Hi,
Recently I posted a problem that I had with a strange noise from the back of the car when releasing the throttle like a pressure release of some sort. I also had a weird juddery feeling when flooring the throttle in high gears.
I'd decided to clean the EGR and the intake manifold as it seemed exhaust related but could get neither off the car due to access to bolts (AJM PD engine). Anyhow, while I was in there I found a kinked line (vac I think) into the EGR at the diaphram so I cut it back and the noise has gone, as has the juddering. Seems like the EGR was stuck closed all the time.

However since, whether it's related or not, my Turbo is kicking in at 2000 rpm instead of the 1400 rpm or so that it used to. It's making the accelleration from a standing start absolutely terrible without revving the hell out of the car, although the pull from the turbo at 2000 rpm in 5th (around 55mph) is an awful lot better than it was.

I'm starting to think now that the fixed vac line has opened the EGR but it's not operating at all (just stuck open) as I'm getting an awful judder when switching the engine off and I think it's the EGR closing for 3 seconds on switch off that eliminates this.

I ohmed out the EGR sensor (I think that's what it's called) that sits up over the MAF with the two pin plug and I'm getting 360ohms across the pins on the sensor. I had been told that it was supposed to be around 10 to 20 ohms only so it may be faulty.
Does this sensor operate the EGR valve? And if so, could this be the cause of the turbo problem?
If anyone's any experience of this, the help would be much appreciated.

Cheers.

P.S. Could it be the MAF either? I cleaned mine but blew it out both directions with an air line. A mechanic told me that blowing through it opposite the arrow can damage it, even if it's out of the car. It's a Bosch MAF.

[Padwick]

I've put in a new MAF (0281002216) but it's had no effect. Probably even worse with the turbo now kicking in around 2200 rpm. Wouldn't pull your fly down at the moment.

The valve in question I've mentioned above is the "Intake Manifold Flap Changeover Valve", not the EGR sensor, but I can't seem to get one for diamonds. Are those valves dealer only parts and could it be a possible cause?

Edit: Vagcat show it under Skoda Octavia only with the part number "038131529..." or "1J09062...". Would an Octavia one do?

[Padwick]

Couldn't edit previous post but wanted to add a pic of the item in question.

It's the one with the round grey top that says "Made in USA" on it. (Made in USA could be a good indication as to why it's not working!).

Top of pic is the heat shield for the air box and the big plug at the bottom is the MAF plug (for location purposes).

[Padwick]

Right, after talking to a guy I know that works for VW, it turns out that the valve in the pic above is only to close the intake valve to stop the engine juddering on shutdown. It's blown but not my problem.

In the past week my turbo has been cutting out altogether around 3000 revs. In this situation the car can't even go up a hill in any gear without losing speed. If I stop the car (even knock it off an on while moving) the turbo works again for a while. He reckons it's the N75 valve down the front of the engine behind one of the fans.

Anyone else experienced this and if so, is it hard to change because it looks very tight to gain access to the bolts that hold it on.

Also, I've a part number 1J0906..... but I'm not 100% sure. Anyone confirm this?

[89Polo]

Hi, I'm driving a 2001 A6 1.9TDi estate at the moment.

It's not my car, but had a Passat SE (essentially the same car), so I know how it is meant to perform.

This A6 has NO POWER from 3000rpm. It's very dangerous to drive in my opinion, since when you pull out from a junction it's as if it stalls

I took it in to AUDI who roadtested it 3 times in the hour they had it and although there is no fault code, there is something wrong with the car. They fitted a new MAF and said there was a mild improvement, but a suspected Turbo boost problem is to blame? The car is going back to AUDI for up to 3 hours on Wednesday

Will let you know how they get on.

[89Polo]

AUDI had the car for two hours and determined the following:

1. The MAF was faulty
2. The Air filter was completely blocked
How is it possible for an airfilter to be completely blocked and letting particles through that subsequently blocked vacuum pipes, to I guess the turbo, when the car was serviced BY AUDI IN LONDON less than 6000 miles & less than 11months ago???

The car has a FULL AUDI history and for the past 3 years was serviced at the one in London.
The car usually goes to Sainsbury's and back and up the motorway, so no idea what blocked the filter.

But for now I'd say check the filter and replace the MAF and clean all the pipes etc. The bill will be about £400 to fix this issue.

Will investigate further and report back when I know more.

[Padwick]

£400 sounds very pricey for an air filter (£10) and a MAF (£70), but then again that's dealer labour prices for you.

I changed my N75 today. Was going to take pics and post a guide to doing it but I got preoccupied as it's an absolute session to change. From the bolts to the pipes, it's a nightmare access-wise. Not tried the car yet but I'll post back if it's fixed or not. I've changed my MAF and I have a foam air filter instaled which I blew out last week, so if this doesn't work then it'll be a turbo for me I'm afraid.

[89Polo]

£400 sounds very pricey for an air filter (£10) and a MAF (£70), but then again that's dealer labour prices for you.

They had to clean all the pipes, because the filter had let loads of stuff through They say they're 99% sure that it's fixed and they will test it again in the morning from cold. I will collect it on Saturday when they are sure it's fixed. I knew it was 110/hour before I took it in. The car has always been serviced by AUDI.

In the meantime I will be looking for a few answers from the London dealer
What they don't realise yet that if I'm not entirely satisfied I will have no issues ringing AUDI HQ in Germany and explaining to them exactly what goes on here.

[Padwick]

Mine didn't work. Car is acting exactly the same as it was on my first run since installing the sensor. Turbo still kicking in above 2000 revs, which is way too high for a vastly underpowered such as a 115bhp one. Don't know what to do with it now.

The second new N239 doesn't work either, does anyone know if these are all fed from the same fuse/relay?

[89Polo]

The London Audi dealer claims the reg doesn't come up and that they have changed their computer system..... That OK peeps, will dig out the receipts at the weekend

The Audi Service Centre told me that the airfilter gets replaced every 40000 miles which seems high, BUT it was serviced less than 6000 miles ago and it seems they didn't even inspect it, let alone blow it out. That's mechanic's 101 Check the airfilter, check the oil

Will look into it further, because AUDI in London were told that my dad wanted to buy the car off the company and that EVERYTHING should be done, regardless of cost

If I find out they didn't do the filter or even check it, THEY can pay for the repair. THAT is the bonus when you go to a main dealer.... they HAVE to put it right.... otherwise they got annoyed customer standing in the dealership loosing the plot.

Just heard back from the service centre again... the car is way way better, BUT is still lacking in power a bit Possible turbo gone

I said leave it at that for now until I can investigate a little further into the history...