aussie_bob

I have not run my 2013 Cayenne diesel for some time and decided to run it in the garage for about 15 minutes with the garage door open .
The car is front in, so I expected the exhaust to escape through the open garage door.
I normally back it out but for some reason left it in the garage idling.
When I returned to turn it off after about 15 minutes, the check engine light was on and ( like a lucy dip ) I scanned out these codes.

P2201
P2209
P22EE
P206D

I can't recall the order but assume the first code maybe triggered the others.
I decided to run it this weekend and after about three starts and highway miles, the check engine light went off.

My question is if these codes could be from sucking in exhaust fumes instead of fresh air, or could all this be a coincidence ?

Thanks in Advance, Bob.

aussie_bob

Went on a BBQ run to Llano Coopers this morning and picked up these codes
P2209
P206D
When I was about half way there ...

I will see if they go away after several driving cycles .
I looked them up and they seem kind of nasty related to DPF and NOX sensor.

If they don't go away , I plan to clear them and drive .
If the CEL comes on , stop and scan out incase one code is a "side-effect" of the other.

Q: Is there a way to see the history of which code was triggered first ?

aussie_bob

I believe the code is P226D ... "particulate filter (DPF) substrate bank 1 has deteriorated or is missing".
I dug into it some and the DPF has a sensor to measure the differential pressure across it .
If the differential pressure is too low then something is up with the DPF and if the differential pressure is zero , then is is missing ie fell off ( ha ha ).
Well I inspected the sensor and it is there and connected Ok ...
When I went under the car a heat shield was loose with 2 out of 3 bolts missing but that didn't seems too bad.
Inspecting the pressure differential rubber hoses that connect to the DPF , they were both disconnected with the retaining clips still in place !.
I will include a images but I plugged them in, one is a smaller diameter and went for a test drive monitoring the DPF differential pressure.
First I had an x-y graph against time and didn't really see anything.
I then changed to a needle display with a digital readout in PSI and read 0 to 0.1 at idle and increasing to 1.3 PSI under medium acceleration . Is that in the range ?

Question is this code came on on a road trip and how would both hoses come off at the same time ? My only theory would be some high pressure event that
caused them to come off but it is a stretch. Has anyone experienced this code with the two hoses off at the DPF ?

Pipes don't look perished and clips look Ok .

aussie_bob

Observe that there is soot on the larger metal pipe for the differential pressure measurement across the DPF.
I would not expect that unless the clip is failing or the clip was on the wrong place . I will check that .
Also observe black soot on the upper side of the DPF ... I will try to track down the source .

aussie_bob

Should I take my images to the local Porsche dealer of would they be thinking they need to get the car in since it is beyond the Diesel gate warranty is over for me .
I did go to my independent guy and he said with the DPF they rip everything out and replace everything from new ... I know that would be about as much as the 2013 / 84k CD is worth so don't want to go that route ... The face that DPR pressure hoses have come off is huge ... I just want to know why it happened. Can anyone help ?

hotrod2448

That’s weird. I would think anything that could generate enough pressure to blow those off would have other noticeable side effects. Like the exhaust being so plugged that the engine wouldn’t run.

I would assume they would likely just cut the hoses but, any chance someone was trying to steal your dpf/ cat while the vehicle was not being used?

Either way if the dpf is damaged and you don’t want to spend the money to replace the hardware your options are pretty limited.

aussie_bob

Thanks for the input hotrod2448.

This code came on during a road trip on the way back to Austin.
I can't explain why they would be off both at the same time and agree they would be cut if someone wanted the DPF.
I measured the differential pressure and it was zero so figured the sensor was bad since the DPF was present else the insides were missing.
I was looking around to make sure there were no issues at the DFP and felt the hoses loose. In addition a heat shield held on by 3 bolts was loose with
two bolts missing .

I reconnected the two hoses and did a road test and the pressure differential goes to 1.3 PSI under acceleration I assume that is as expected.
I am going to measure where the spring clips are to see if they were installed in the correct position. I don't really know if the clips are one time use .
I may add after market clips if necessary.
I am also interested in the black soot on one of the DFP pressure differential pipes where the hose plugs on I would not expect black soot there or even on the top of the DFP meaning something may have been leaking.

The test will be if after running some miles to get systems to readiness, that the P226D code doesn't come back.

Finally, I can't see that a stick or road hazard would do this without some other issues.
The car showed no issues when the code came on at highway speed and still drives great.
Feeling exhaust at the rear pipes doesn't indicate anything is blocked.

garrett376

Is that picture of the 2 hoses how you found it? If so, someone didn't install the hoses properly - they never put the clamps back in position. Those spring hose clamps won't slide down the hose on their own.

aussie_bob

Thanks Garrett376,

This is exactly as I found it when I was inspecting the DPF pressure differential code P226D indication the DPF was missing .

I can do a close inspection based on your thinking to see if the clamps have been moved as there is normally some mark where they
have been seated for some time.
If the clamps have moved then as you say the logical explaination is that someone removed the hoses.
I also plan to measure where the clips are at present to see if they are positioned as expected ... I pushed the poses back on just to
measure the DPF differential pressure sensor output on a short test drive and it takes quite some effort to push the hoses on 1/2 and inch .
I didn't touch the clips that look like they need a special tool to compress them.
The only other time the vehicle was out was to an Independent Euro shop to replace the battery after 10 years and code it.

The vehicle went to Porsche for the "diesel gate" fix that I assume was software and not a new DPF.

The other rime the vehicle was at Porsche was for an O2 sensor where the heater circuit went out. Replaced the O2 sensor in the engine compartment.
I don't think they would have messed with the DPF hoses for that .

Here is my main question ... Q1: How long does the P226D code take to fire if the hoses are disconnected ?

We went to the Canadian border and back from Austin and no code.

We then went to Llano for BBQ which is say 100 miles and the P226D cam on half way on the return.

Q2: Should I ask the Porsche service advisor I have worked with if he has ever seen anything loke this before ?

reneeweiss

It is cheap to ask the service adviser. There were hardware fixes as well as software to the diesel gate fix, perhaps the hoses were loosened then.

garrett376

How long have you owned the car?
Likely a repair was done in the past, the hoses were slipped on without placing the hose clamps in position, the tech continued on and never returned to place the hose clamps in their proper position, and here we are today. I have never seen a hose clamp of this type "slip" out of position. It was loosened, moved, and not put back.

aussie_bob

Hi Garrett376,

I purchased the 2013 CD new from Penske Porsche in Ohio
Except for the "diesel gate" required fix , it has only been to the local dealer for .

1. Oil Changes when it was kind of new.
2. Once I had an Add Blue alarm went off when I went around a corner and they fixed it.
3. Attempted to fix an oil leak/seep at the back of the engine near bell housing. Still has oil leak / seep there.
4. New set of tires
5. O2 sensor replaced where the heater side was giving a code. O2 sensor was the top one near the firewall in the engine compartment.

The only other work was after 10 years the independent Euro car shop replaced the battery and coded it.

Everything else I have done myself . Main issue outside of regular service items was "black death" on one fuel injector where I had to replace the copper pressure washer that was leaking ( see another thread ).

I will take another look at if there are more forensics / evidence pointing to how this happens.

hotrod2448

I assume the soot present is from the hoses being disconnected and the back pressure of the dpf causing exhaust to blow out the pressure tap.

It might not be out of the question for the tech to have disconnected these during the O2 sensor replacement. They replaced my catalytic converter under warranty during the engine reseal when the O2 was found to be galled into the pipe. Depending on what a PITA yours was to get out they may have decided to drop the cat and dp out the bottom for better access.

aussie_bob

Thanks ReneeWeiss,

I will put my good clothes on and swing by there tomorrow ... I know people at the dealership so I may be able to triangulate some .
There should be a document that spells out the procedure to update the Cayenne diesel as a result of "diesel gate" .
All I recall was that they said there would be greater hysteresis or similar when the throttle came off .

aussie_bob

This is the top O2 sensor they replaced.

I doubt they did anything under the car as the code was calling out the specific O2 sensor ... I would have replaced it myself except that it was covered under the "diesel gate" extended warranty like first 10 years. ( what was annoying was the $325 / hour "diagnostic" charge when the code kind of does all the diagnostic work for you ... all you have to do is pull out the O2 sensor that the code identifies and meter the heater circuit and you are done . I was told this charge is not included in the extended warranty which was probably part of the negotiated settlement ).