RS2 not running clean at WOT with boost

[minim]

Recently bought a RS2 -94 that had a problem with not running clean when the turbo pressure comes. The 1. gear is pretty good but from 2. and up it has hesitation and gives a weird sound while revving up. I have cleaned the MAF, now recently changed from AAN/ABY cam pulley to ADU cam pulley with the hall window at the right spot and I've checked the intake for leaks (just with 0.1bar pressure or so). I'm open to suggestions to what to do. I got vagcom and I can log more or different if that can reveal something.

I tried to log the problem revving up on 3. and 4. gear but I don't think I got the error logged. The .CSV file is here tho if anyone want to have a look at it.

http://lokalhost.org/audi/vagcom/log_problem.CSV

This is what I get as a readout when I check for errors with vagcom.

Saturday,17,August,2013,09:37:32:08464
VCDS Version: Release 11.11.6 (x64)

Address 01: Engine Labels: None
Control Module Part Number: 8A0 907 551 B
Component and/or Version: 2,2l R5 MOTR.RHV RS2D03
Software Coding: PMC 4
Work Shop Code:
VCID: 264348F7C2C61D287A7
1 Fault Found:

65535 - Internal Control Module Memory Error
00-00 - -

Readiness: N/A

The sounds that sound like it's a bumpy road are the engine hesitating and not revving as it should. It was hard to capture it on video but you feel it really good when driving.

Just in case the youtube videos in the forum don't work the links are here. Video 1 link - Video 2 link

[twoqu]

Do you mean 1 bar? I take it you have been educated about the pressure test procedure. The Forum method is to blow though the Maf hose and remove the engine breather connection leaving it open and bung the hole in the maf hose.

[twoqu]

One posibility:

http://www.s2forum.com/forum/showpost.php?p=675143&postcount=13

[minim]

Do you mean 1 bar? I take it you have been educated about the pressure test procedure. The Forum method is to blow though the Maf hose and remove the engine breather connection leaving it open and bung the hole in the maf hose.

No I mean 0.1 bar I need to make a better tool to do a safe test at 1 bar. If I'm not wrong the bung will have approx 200 kg of force on it at 1 bar and I doubt that my tool will survive that. At least I don't want to try and have it shooting all over the place. Will see if I can come up with something. Is it indication of a air leak?

To answer your questions from the other thread.

Do you know whether the vehicle has been modified, i.e. chipped? If so do you know the origins?
Has that altitude sensor value changed to something more accurate? I don't think it makes a massive difference unless of course as mentioned previously it is acting as that towing power limiting function. The value was suspiciously close to the published one!

Yes, the previous owner told me that it has been chipped and I do not know the origins. I was planning to remove this but haven't gotten around to find out how to do it. I want it stock

Yes the altitude sensor was now showing 900 something. I thought I logged it but I must have forgotten to do that. I didn't check if it was showing the value that it would show if it was broken, but I don't think it was showing that value.

[twoqu]

Well its just there are so many places that can have a leak thats its good practice to check before chasing other faults. Apart from the obvious large hoses there are other not so obvious places like the intercooler O ring, injector inserts and all the other small bore hoses/engine breather components that a decent amount of pressure can reveal in one test. Once you are fairly confident that its leak free you can move onto any codes. In this instance you do have one that needs attention.
I can understand your reservations about the method. You could argue that the maf hose is only subjected to vacuum not pressure but as you are only testing for a short period is does not seem to do any harm.

[RS2 driver]

Hi

Have you checket spark plugs??

I had a kind of similar problem after changing spark plugs from the original Bosch F5POR to a NGK regular type with copper core. I have now changed to NGK type with Iridium core and now runs OK at WOT.

[minim]

Well its just there are so many places that can have a leak thats its good practice to check before chasing other faults. Apart from the obvious large hoses there are other not so obvious places like the intercooler O ring, injector inserts and all the other small bore hoses/engine breather components that a decent amount of pressure can reveal in one test. Once you are fairly confident that its leak free you can move onto any codes. In this instance you do have one that needs attention.
I can understand your reservations about the method. You could argue that the maf hose is only subjected to vacuum not pressure but as you are only testing for a short period is does not seem to do any harm.

Ok. Will look into it. The fault code might just be the chip that's causing. I noticed when googling it that many had this issue with chip installed.

Hi

Have you checket spark plugs??

I had a kind of similar problem after changing spark plugs from the original Bosch F5POR to a NGK regular type with copper core. I have now changed to NGK type with Iridium core and now runs OK at WOT.

No I didn't check them other than taking them out to see what's in. It was "Bosch Platin R1 111" that was installed. Not the original ones then

[twoqu]

Certaintly a possibility I am afraid. Unlike more modern cars the eproms need to be physically removed and either erased and the OE files burned onto them or perhaps, as most people on here will have done, you consider an upgrade from a reputable source which enhances the vehicle. We do have someone on here with the experience and know how!

[twoqu]

Could also try cleaning up the earth connections at the inlet manifold.

Also might be worth fully charging the battery if the cars has been sitting around dismantled. I noticed that it was about 11.5V during the first Vag com testing you did so perhaps its picked that up as a low voltage. Clear the fault and see if it comes back.

[twoqu]

Does the vehicle have a stock dumpvalve i.e recirculating rather than atmospheric?

[UrS4boy]

3B, ABY and ADU boost leak pressure testing

Minim: Not sure if you have a boost leak or not but you need to eliminate boost leaks as the potential cause. As Robin (twoqu) says, there are many possibilities for boost leaks, not just in the turbo to intake manifold tract but also in the various PCV and evaporative emissions pipes and hoses if things go bad.

As per his (and prj's) suggestion, to capture all the potential leaks at once, you place the pressure bung in position A1 and you disconnect and plug A3 in the diagram below. If you pressurize to 1 Bar, that should be enough to find a leak. You are worried about the bung blowing off. Remember that the clamp that holds the hose on has no issues at chipped pressures, e.g. 26 psi (1.8 bar boost).

More boost leak testing info: http://www.s2forum.com/forum/showthr...538#post709538

[UrS4boy]

Does the vehicle have a stock dumpvalve i.e recirculating rather than atmospheric?

Minim: Adding to twoqu's suggestion, click on the link to the diagram below and then click on the Diverter Valve label (note: all the labels on the diagram are hot links to more info about those devices, you might want to visit more of them). The ignition coils label leads to coil and spark plug info *AND* a link to a missing and hestitation diagnostic procedure that you might want to check out.

http://members.shaw.ca/speedtek/UrS%20Engine%20Bay%20Device%20Map.html

[DJones]

I don't think I would rule out fuel pressure either, check the pipe that goes to the fuel pressure regulator isn't split, another simple check before going to far.

Again a boost pressure test would find it.

[minim]

Certaintly a possibility I am afraid. Unlike more modern cars the eproms need to be physically removed and either erased and the OE files burned onto them or perhaps, as most people on here will have done, you consider an upgrade from a reputable source which enhances the vehicle. We do have someone on here with the experience and know how!

Will prolly update the one that's installed anyways as I want the original setup back. It could be a part of the problem also who knows

Could also try cleaning up the earth connections at the inlet manifold.

Also might be worth fully charging the battery if the cars has been sitting around dismantled. I noticed that it was about 11.5V during the first Vag com testing you did so perhaps its picked that up as a low voltage. Clear the fault and see if it comes back.

Do you mean the cable that's mounted on the top cover and goes from top cover to coil cover? That one I cleaned when I had it open to mount the new oil seal for the valve housing.

On the last tests it was showing 14V while driving. I think the reason it showed 11.5 was that it had ignition/lights on for a while when I was working on solving the issue of not getting connected to the ECU. I did charge it after that while I was putting the car back together. It's less than a year old and I haven't noticed any problems with it yet.

Does the vehicle have a stock dumpvalve i.e recirculating rather than atmospheric?

It has a brand new OEM dumpvalve fitted today as it had a aftermarket alloy thing.

Minim: Not sure if you have a boost leak or not but you need to eliminate boost leaks as the potential cause. As Robin (twoqu) says, there are many possibilities for boost leaks, not just in the turbo to intake manifold tract but also in the various PCV and evaporative emissions pipes and hoses if things go bad.

As per his (and prj's) suggestion, to capture all the potential leaks at once, you place the pressure bung in position A1 and you disconnect and plug A3 in the diagram below. If you pressurize to 1 Bar, that should be enough to find a leak. You are worried about the bung blowing off. Remember that the clamp that holds the hose on has no issues at chipped pressures, e.g. 26 psi (1.8 bar boost).

More boost leak testing info: http://www.s2forum.com/forum/showthr...538#post709538

Will see if I dare to put 1bar on it I def need to secure my plastic test tool as I'm 110% sure parts will come flying as I apply that pressure on it.

That was how I did the test before but then at a lower pressure. The clamp on that hose never holds 1.8 bar as this is the side of the turbo that's under vacuum and due to the size of the intake there will never be any negative pressure to speak of. If you look at the connection of the MAF you will also see that the pipe is not made the same way as the hose connection that is built to be set pressure on not that it matters as MAF is removed while testing. I will just have to build something from a metal pipe so I can have more pressure on the clamps then it's safe to do it.

Minim: Adding to twoqu's suggestion, click on the link to the diagram below and then click on the Diverter Valve label (note: all the labels on the diagram are hot links to more info about those devices, you might want to visit more of them). The ignition coils label leads to coil and spark plug info *AND* a link to a missing and hestitation diagnostic procedure that you might want to check out.

http://members.shaw.ca/speedtek/UrS%...ice%20Map.html

Thanks again for good links

I don't think I would rule out fuel pressure either, check the pipe that goes to the fuel pressure regulator isn't split, another simple check before going to far.

Again a boost pressure test would find it.

Hmm. The guy I bought it from said that it came not long after that he replaced the fuel pump so it could be related to that maybe

Will search some for products for data logging. Would be fun to have a high resolution data logger that could log turbo boost, timing, rev, fuel pressure, oil pressure, temperature, afr and so on instead of having loads of gauges.

[twoqu]

That sounds like just the earth for the coils. If you face the engine, under the inlet manifold at the rear should be some cables attached.
Have you orientated the DV correctly?
Data logging does exist I think but that might mean considering the ecu upgrade sooner than you think! Obviously if the car has a fault that effects it then its better to troubleshoot it before you put any more stress on it. Once its performing as it should and you get used to it, I guess you might be interested in more!