Good to hear.

I wonder if there's potential DIY in here, if all they did was clean it.

 

Had the exact same problem with my '16 Cayenne. Was very laggy and then threw up the codes you shared. The dealer replaced the catalytic converter. The transformation has been dramatic - my wife said 'I had forgotten how fast this car is'. It feels like our '14 CD felt.

Seth
'16 CD
'09 C2S

 

The more of this I'm reading the more I want to bypass the EGR sooner rather than later.

 

Is it me or this is the main difference between the 2.1 and 2.2? The 2.1 CDs have new emissions hardware replaced while the 2.2 is just software.

While my 2.1 behaves different than pre-fix, I don't have that huge lag that some of you guys post. I have driven it about 1000 miles since the fix (both short and long distance) and, honestly, but for a couple of occasions, I am fine with how it feels

 

If EGR is easy to get to then cleaning it is not difficult. Regular oven cleaner and some elbow grease works well. You just cannot leave oven cleaner on EGR for a long time like overnight or days as it is corrosive to aluminum.

 

Found this in YouTube:

 

As the video above shows it doesn't look easy to get to. Then there is the gunk it builds up in your intake tract that you also have to clean out.

Unfortunately I'm not aware of anyone bypassing it on a 958 (or comparable Touareg/Q7 either but, I have not really looked into those vehicles). I'm not sure what issues would arise from doing it without a tune geared for it. Outside of CELs I would be more concerned that the mixture would go leaner than ideal because you would effectively be replacing the recirculated exhaust gas with air. Of course the ECU should compensate for that by monitoring EGTs and O2 levels but, who knows how far you can push those without a CEL.

If we had some tuning options for this platform I would like to delete the EGR, DPF and DEF but, options are quite limited for that stuff right now.

 

The Cayenne mech at Hoffman explained to me that he spends hours scraping carbon out by hand, it didn't sound like a fun job. The BMW guys use walnut blasting, not sure if that can work on ours also, but I'd like to look at a better AOS and/or EGR bypass if possible. I think I've read that Malone tunes can support the 'alphabet delete' (EGR, DPF) but haven't looked too closely. Not interested in rolling coal, but I would like to avoid a rehash of this if possible. I'd also like some more torque, towing my STI versus the Honda is a lot different trying to climb hills on the highway. The extra 1500lbs is really noticable.

 

I have not had mine fixed yet. I don't need to fix it in my state. We have no inspection for emissions. Based on what I read, I fear I would just spend the money in a trade for a new car, when I am happy with the Cayenne Diesel I have.

Tell me again why I should have the fix done? The upside is money in the bank and a lot of hassle with my dealer 2 hours away. What is my downside if I do not?

 

It looks like removal of airbox and cosmetic engine cover to me for access to both parts. Well, also after opening the hood.

EGR cleaning..

 

I already called a Malone tuning dealer in CT. They will not provide those tunes in CT. You can probably get them in states that do not require emissions testing but not sure you will pass CT emissions after.

 

You are leaving out the additional work of getting that same build up of carbon and gunk out of the intake side of the engine. I mean if you want to just clean the EGR valve that's great but, if its plugged there's a good chance the other components need cleaning as well.

 

I am going through this right now on my GL320 that is 9 years old with 69K miles. The carbon deposit on intake valves and manifolds requires cleaning. You can Liqui Moly it every 15-20K miles or open it up one time in a car's life. This is happening to all direct injection gas or diesel motors with EGRs and not a diesel specific issue.

 

This is great. Just would love for someone to show us on the Cayenne Diesel. More step by step.

Thanks

 

+1 on Cayenne diesel specifics needed