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It would not be my first choice to get it apart but you could try with a screw driver   Go into the gap which is already there or use a coin. Try. 

 

Or like you say you want to disconnect it from the turbo.  I had to do it because my air hose was broken.

little bit more work. Take away all the plastik protection under the car.  Or you take away the wheel well liner to get access to this place. 

 

Lewis would say.... when you are there you can check the connections of your DV and the tubes and hoses arround for any visible leaks or damages. 

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Well, that could have gone better, but I guess it could have gone worse as well. It finally dawned on me to just do the passenger side first to see how these tubes come apart...I traditionally do the easiest side last. The MAF tube rotated as soon as it was unclamped, so there is in fact a problem with the driver’s side. I didn’t take the tube out on the passenger side, as it was easy to unscrew the sensor right there, and the whole side took about 15 minutes to do.

For the driver’s side I gave up with the pipe, and used a chain of extensions and U joints on the ratchet to get the MAF out, 1/32 of a turn at a time. Cleaned both, but was a bit worried because in my efforts to get the tube loose, a few drops of WD40 had fallen into the mesh in the MAF tube. Cleaned it up the best I could and fired it up. I will take it out in the morning for a run, but I have that what have I done feeling about this – it was running OK before; still hard to start when cold and would get a bit shaky at idle after driving in traffic. But when I started it, it backfired out the driver’s side like crazy, gurgling and backfiring as I revved it. After warming up it got better, but now the idle dives down too low after letting up on the pedal. After cleaning do things have to re-train it somehow? If so do you turn PSM off for a while? I will see how it is after blowing it out tomorrow. There is also a definite oil leak somewhere on the left front region of the engine. Hard to get a good picture, but this is looking forward from the sway bar mount on the driver side.

DSC04049s.jpg

 

I really hope this runs better and not worse now!

 

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Zakowsky,, don't give up on the assembly of that flow pipe downstream of the MAF. When I was doing my Alt RE&RE I noticed that my pass side flow pipe wasn't fully connected and I felt I couldn't follow in the steps of previous (non) assembler. I struggle with it. I very thinly smeared Vaseline on the male side of pipe (piece connecting to air box) to facilitate, but it eventually made a satisfying snap as the ribs completely seated and provided me with an uninterrupted flow pipe to Turbo :clapping:You could also trying heating the female end of the pipe to slightly expand it. I would think it could handle more than enough heat needed for fitting given its location in engine bay

Edited by gravityalwswins
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I didn’t think about heating up the pipes – good idea, thanks. After some more work, the MAFs are finally cleaned and everything is all back together again. Classic 1 hour job that takes 5 hours! But to wrap this up, I thought I would post the results. Before/after observations, although the after has only been for about 40 minutes of driving.


1) Before there were starting problems – up to 5-10 seconds of cranking when cold to get it to start. Tested this twice so far, each time it started instantly!
2) Before there was an unevenness between left and right exhaust. Seems better now.
3) Before the idle would randomly get rough – after it has been smooth at every stop light.
4) Not much change in overall power
5) New behavior when the engine drops down to idle. Before it would go smoothly down to around 550-580 rpm. Now it dives down to 400 rpm, then picks back up to 550. Sounds like I should also clean the throttle body now? Or maybe it needs to adapt again...
6) Right after cleaning, I was freaked out because it was running like crap, backfiring and coughing on the driver’s side. After running it for a while in the morning, that was all gone (big relief!).

So as it is maybe one of the last nice days here in Alberta for the year, going to try and get out for a run in the mountains today. Believe it or not I just learned what turning off PSM really does (I thought it was just regulating the suspension). Need to play around that a bit. Thanks again for everyone’s help.

 

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8 hours ago, Zakowsky said:

I didn’t think about heating up the pipes – good idea, thanks. After some more work, the MAFs are finally cleaned and everything is all back together again. Classic 1 hour job that takes 5 hours! But to wrap this up, I thought I would post the results. Before/after observations, although the after has only been for about 40 minutes of driving.


1) Before there were starting problems – up to 5-10 seconds of cranking when cold to get it to start. Tested this twice so far, each time it started instantly!
2) Before there was an unevenness between left and right exhaust. Seems better now.
3) Before the idle would randomly get rough – after it has been smooth at every stop light.
4) Not much change in overall power
5) New behavior when the engine drops down to idle. Before it would go smoothly down to around 550-580 rpm. Now it dives down to 400 rpm, then picks back up to 550. Sounds like I should also clean the throttle body now? Or maybe it needs to adapt again...
6) Right after cleaning, I was freaked out because it was running like crap, backfiring and coughing on the driver’s side. After running it for a while in the morning, that was all gone (big relief!).

So as it is maybe one of the last nice days here in Alberta for the year, going to try and get out for a run in the mountains today. Believe it or not I just learned what turning off PSM really does (I thought it was just regulating the suspension). Need to play around that a bit. Thanks again for everyone’s help.

 

The oil on the right side indicates pcv carry over. You need to test your three way check valve and AOS diaphragm. Also you need to remove the lower turbo to intercooler pipe drain the oil clean it and replace the o-rings they are a few dollars only. (this is likely where the oil is leaking from that hose and them o-rings). 

Then sadly you need to clean the Maf sensor that side again and the MAP sensor and the throttle body them do adaption with software (first also clear dtc now to erase fuel trims and learnt values) or if no code reader disconnect battery for 30 mins and after reconnection set ignition to on position with engine not running and let the throttle adapt itself for 60 seconds. Switch the ignition off, then on again and start engine, let it idle for at least 5 minutes and it will be adapted, then go for a nice long drive with cruising and high speed wot bursts. If after all that you still have problems then need to look further into sensor malfunction ie maf or o2 plus more likely vac leak on a pipe somewhere. 

 

Infact I'm doing most of this work myself this week when I get the parts. New oem Bosch maf's, new AOS its split and making screecchh noise under high boost and the lower boost hose is one of the ones I have not yet removed and replaced o-rings yet although my smoke test didn't reveal any leaks I'm anal about these things and after spending so much to make this puppy purr I'm going the whole 9 yards to make it perfect F the cost and my time is free. Its also my escape from the stress of real work. 

 

Got a new upper control arm to do on this drivers side as well so wheel liner, bottom cover and all this stuff coming out anyhow so makes sense to wrap it up into a big job. Will get my apprentice Eng. to take pics as we go through it stage by stage and also will replace the dv vac pipe that side just for the hell of it. 

 

If I had the chance to do it again one time (especially when the engine was out), I would replace all vac and pcv pipes, n75 valve solenoid, change over valve solenoid, check valves, AOS, orings for all boost pipes, with pipe cleaning of oil carry over, replace both maf's, all coils and plugs, water pump, tensioner, belt and idlers pulleys.

Just for piece of mind and future difficulty to change. Alot of pipes can use common pneumatic equipment and not oem expensive pipes. Get original Bosch sensors from them direct for more than 60% less cost. 

 

This list if budgeted and done when buying an old cayenne turbo would give many pleasurable motoring for many more km. (we are assuming the basic are good here, block, valve train and key transmission/drivetrain components). 

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I fully agree Lewis; and it is indeed in many ways an escape from the stress of real work.

 

Thanks for the leads for the oil problems. A quick check of the AOS and check valve looks OK; but I pulled out my MAP and I was unsettled to see how much oil was in my Y tube. Lots of discussion on this online, and I will diagnose next weekend. Externally on the top of the engine I mainly see oil from this connector, under the Y tube where I suppose it drains into. But the intercoolers will be my next thing to look at.

 

DSC04053s.jpg

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52 minutes ago, Zakowsky said:

I fully agree Lewis; and it is indeed in many ways an escape from the stress of real work.

 

Thanks for the leads for the oil problems. A quick check of the AOS and check valve looks OK; but I pulled out my MAP and I was unsettled to see how much oil was in my Y tube. Lots of discussion on this online, and I will diagnose next weekend. Externally on the top of the engine I mainly see oil from this connector, under the Y tube where I suppose it drains into. But the intercoolers will be my next thing to look at.

 

DSC04053s.jpg

After changing the maf sensors I'm happy to report my old ones were probably aging quiet gracefully but sad to report my new ones were likely a waste of money FFS.  I mean a great investment in reliability..........ahem

Just think what that 120euro could have done on a night out in Amsterdam? 

Anyway driving like a bigger turd now I took her back to the warehouse for a talking to. 

 

Tested the DV's and vac pipes all fine, pressurised the wastegates and pipes via the n75 valve pipe connection up to 15psi was perfect not a squeak of air leak from the new home made vac pipes, decided F it smoke it. Did the hilly Billy smoke test and no leaks, opened the AOS expecting it to be broken hence the screech noises but no its perfect no splits or anything (new one I ordered over a week ago still in the post according to Russian Federation tracking, 4 days flying from Russia to uae? Must be one of those solar powered planes or something).

Cleaned the throttle body, 

So Wtf. 

Putting the air filter back in the drivers side I see the orange soft rubber outer seal is misshapen at the corner and could possibly leak air past the gap at high air flow and maybe make a silly ballon noise. So I wasn't able to mould it back to it original shape but instead put some pvc tape in the gap before squashing the cover over it. Haven't had time to screech test it yet, just did the throttle alignment on the vcds and checked for dtc, none found. 

 

Here is the post cat o2 sensors graph bank 2 in green is not as Controlled or stable as bank 1, but when I looked at bank 1+2 precat o2 sensor they are perfect steady almost flat  line holding  lambda 1v and revving produces fluctuations consistent with  what would be expected. Even holding at 2100rpm the car shakes as it's obviously not happy but the data still says nope I'm perfectly fine with this carry on as you were. Ffs. Why why why 

So as the condition of the cat and post cat o2 sensor output has no feedback loop it doesn't dictate the engines running I guess this just means one cat is worse than the other? Help

 

Long term Fuel trims are -0.8 and short -3.1. So I'm slightly rich no biggie?

 

Left the piggy in the warehouse as punishment and went home in the Audi. 

 

Tomorrow got a lovely meeting with some D*ck heads in Abu Dhabi so will go swap cars and take the Cayenne for a long run and see what's it like. Probably same as I'm not finding any smoking guns. 

 

 

 

IMG_20161108_155650.jpg

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Hope it ran better on your road trip. Mine is right back to where it started before the cleaning. After reading the “Turbo / MAF replacement, Oil found” thread by ekstroemtj, maybe I should jump these posts over to there; sounds like I am going down the same road. I am pretty sure my driver side intercooler is filled with oil and the seal is shot. Project for the next weekend. But I’m not sure how the venturi/crankcase ventilation line connection to the Y pipe (in my photo above) is going to go. It is soaked in oil so probably leaking, but you might even be able to see it, it is at a bit of an angle where it attaches. Probably why it is leaking, and if oil is coming out, I imagine air is getting in. Tracing the line back it also doesn’t seem quite aligned with where it should be, and since it is so inflexible, not sure how I am going to get it seated. But with all that oil in there, I’m sure the MAF sensor just gets dirty again soon after cleaning, leading to the roughness and hard starting.

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  • 3 years later...

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