chode

Hi All,

I've just had the camshaft sprocket bolts fail on my 2011 Cayenne Turbo. It's covered about 80k Miles.

I was very pleased to have the extended warranty . The engine is now out and undergoing repair at the dealer.

While the engine was out I had a look at the Turbo's and noticed that the drivers side one is chewed up. (See Picture). I had been complaining about a lack of power for over a year and Porsche kept telling me it was fine... I was also only getting about 0.8 bar of boost under maximum acceleration. I'm assuming this turbo could have been the culprit.

My question is - if a turbo has failed like this, what should I expect the repair to include? Porsche are just planning to replace the turbo but I'm very concerned about where all that debris has gone.

Any input would be much appreciated.

Torre

How much boost should it make? My 957 Turbo's scale ends at 0.8 (they make the same power) and it always goes there on full power.

About where the debris has gone - my friend had an engine replaced on his brand new BMW X5, but they left the old turbos in place because they thought they were fine. About a month later the new engine was shot too.

chode

Porsche have given me a replacement 2016 Cayenne S while mine is in the shop. That seems to hit a max boost of 1.2 to 1.3 Bar. The digital gauge reaches the max and the text numbers keep going up.

Then again that is a new car (3k miles) and a completely different engine.
Apparently the cylinder head is off the engine now and everything looks "okay", whatever that means. I'm pretty nervous about any potential damage to parts in the long term.

user 83838290

Have them take a pic of every cylinder TDC as well as BDC plus all valves. If all valves and cylinders look fine, I wouldn't sweat it.

OTOH, chiping a blade is a serious thing - the turbo was either out of balance from day 1 or your oil was too thin to hold the axis where it should be while spinning.

Dan87951

I'm not surprised the cam adjuster bolts failed. Seems like a lot of 2011 Cayenne's are getting this lately. Did you check the turbo for any play? If you can extend your warranty it might be something worth looking into. Good luck and hope they take care of you!

wrinkledpants

Yeah - I'd want the cylinders scoped at a minimum. That's an odd turbo failure. Typically you'll see some tip curl if a blade contacts the housing, but the whole tip of that blade went missing. Any piece of FOD big enough to remove a blade tip is going to do more damage than just that. It almost looks like the blade had a defect in the metal, and that tip just liberated at some point.

Though, I'm not sure this would cause a low-boost issue. It certainly won't flow as much as a good turbo, but the MAP sensor is at the throttle body after both turbo air streams have merged. So, if the car is requesting 1 bar, it'll keep the waste gates closed until it reaches that. The other turbo has more than enough headroom to make up the difference. The car doesn't know what each turbo is producing for power, it only knows what manifold pressure is at the throttle body.

I'd want both turbos inspected, compressors and turbines. If that piece went through the motor, it most certainly went through the turbine section of the turbo, possibly leaving some FOD damage in the turbine section.

hahnmgh63

In addition to what was said above, both Intercoolers (especially the one on the bad Turbo side) need to be flushed with solvent. It's probably time to clean them anyways but usually any sizeable debri from Turbo damage gets filtered out in the Intercoolers. Very small debri can still get through and into the engine so a borescope (video nowadays) needs to be done on all cylinders as was mentioned above.

rloggie

Having bought a 2011 CTT this week, I had the P dealership inspect to confirm that it had steel bolts in the cam tensioner. It does. Does this event only happen to those with aluminum bolts?

Krisek

how did he confirm that you had steel bolts ? what is the production date of your car ... if you provide VIN we can look it up ...

stephen k

I would be more worried about what caused the turbo to chip and where that chipped piece is now.

Stephen

sterz85

how would you check it? can you check if my VIN is affected? WP1AC2A26CLA81143 , production date September 30, 2011

Also, the following two cars had the issue, do you know if their VINs show up in the WC22?

wp1zzz92zbla86307
wp1zzz92zbla49745

hahnmgh63

His turbo being chewed up had nothing to do whether he had Aluminum or Steel bolts for the Cam tensioners, that is a whole other problem with early 2011's. Now if the engine was running bad from a bent or broken valve and it got into the exhaust it could be possibly cause a Turbo problem but by then you would be down on a lot of power and have other issues.

chode

Yeah, I think the turbo had probably been like this for a while. I only discovered the problem because the engine was out for the cam adjuster bolts.

According to the dealer, my car had already had the WC22 campaign and the cam adjuster bolts replaced. Strange that they still failed.

The cylinder heads are off so I'm heading down there today to have a look and get some pictures of the cylinders top and bottom DC if they will let me. I'll also make sure they're flushing the intercoolers. Interesting that this shouldn't have affected performance though, no idea why the power was down. Anyone know what the actual max boost should be and if 0.8 bar is fine?

J'sWorld

" If they will let me"?
Who's life is this?

Jimbabwe

Sitting here thousands of miles away, not knowing the facts or having the evidence in hand, yet I feel that I have to say...
I have a hard time believing that the problem seen on the turbo impeller in the picture has been like that a long time. The amount of mass missing coupled with the speeds that are achieved on your turbocharger equals a metric ****-ton of vibration. I believe that you would have noticed...?
Also, it appears that the oil residue seen on the blades is not present at the fracture surfaces. This would suggest that the fracture is relatively fresh. But it could just be because of the image quality, or that the surface is parallel to the flow of air, or I don't know what I'm talking about (most likely).
Either way, the cause of the fracture needs to be investigated...