Dealership Offerring "Upper Air Intake Service" That's Not on Service Schedule ?

[ANDY54]

I'd appreciate any advice or experience with dealerships offering an "upper air intake service" as an extra part of the 45K service schedule for the B8 Passat TDI. I live in regional NSW so I drive a balance of rural roads and the M1 motorway.

After leaving the vehicle for service, the dealership rang me and claimed they have found that the Passat TDI models build up "a lot of carbon" around the upper air intake and linkages that should be "cleaned out" every second service. They look at it as "preventative maintenance" for the customer at an extra $150. This added extra was never "offered" for my B7 Passat TDI

As I didn't have the service booklet at hand, I checked with VW Australia over the phone and they couldn't find any reference to this being part of the 45K service. So there seems to be no supplement for this extra maintenance under Australian conditions.

I'd be the last know about the inner workings of diesel motors. Maybe I'm missing something in keeping this vehicle running at its best ?

[Lucas_R]

Well have a look here at how my TDI looked after 35,000km and I had error codes for blocked intake valves.

I cleaned it myself and now do a diesel specific intake clean every 6 months before an oil change as preventative maintenance.

The joys of today's emissions rules and the introduction of EGR valves etc.

P2006 error on 2015 Audi SQ5 TDI with 35,000km

[ANDY54]

Thanks for the feedback so quickly Lucas. That's a serious amount of carbon in those photos. Do you think my Passat would look like that?

I take my hat off to you sir, you have the ability to pull down the air intake and clean it on the bench the correct way. For $150 the dealership was only going to blast a tin of solvents through the air intake. So wouldn't that flush all the carbon down into the Passat's motor ?

[doc_777]

EGR off-take on the 140TDI motor is after the DPF. That will massively reduce the amount of soot at the egr valve.

[Lucas_R]

Yes the amount of buildup in my car definitely took me by surprise and I was not expecting it to be that bad on a 3yr old car with 35,000km. Granted, we did buy it 2nd hand (3yrs old and 28,000km) from Melbourne so I can only speculate that it was driven alot in Melbourne traffic.

I dare say the intake in your Passat would be somewhere along the same lines, but the situation is made worse by lots of idling and light throttle driving (stop/start traffic etc) as the EGR opens at idle and low throttle which will make the soot accumulate more quickly. I suspect that the car I bought was regularly used in Melbourne city traffic with lots of idling and light throttle.

The spray treatments that i am aware of are:


Sprays that are available from Supercheap / Repco etc such as this

Penrite P26 Diesel Foaming Intake Cleaner Aerosols 130ml | Automotive Superstore

JLM Diesel Air Intake & EGR Cleaner 400ml | Sparesbox

Liqui-Moly Diesel Engine Intake Decarb - 326g | Supercheap Auto


Or machines that spray a hydrogen or water steam into the engine to loosen and dislodge the buildup such as this:

Engine Carbon Clean NSW - Home | Facebook


Curious to know what type of service VW are offering.

[Jondalar]

There was no mentioned of this when I had my 45k service done last month, but being a 140TDI and 50% highway running it's probably not building up too fast.

[doc_777]

EGR on the 140TDI is after the catalyst and the DPF. If the system is working correctly, there should be basically zero soot circulated back into the intake. Unlike EGR systems of previous generations of Diesel engines.

[Lucas_R]

EGR on the 140TDI is after the catalyst and the DPF. If the system is working correctly, there should be basically zero soot circulated back into the intake. Unlike EGR systems of previous generations of Diesel engines.

If this is accurate then this is a much better design, and also the VW dealer are trying to sell an unnecessary addition to a normal service.

Also, im going to look at mine to see if there is any way i could have my EGR rerouted to after the cat and/or the DPF on my car to slow down the gunk buildup.

[Jondalar]

There was no mentioned of this when I had my 45k service done last month, but being a 140TDI and 50% highway running it's probably not building up too fast.

[doc_777]

If this is accurate then this is a much better design, and also the VW dealer are trying to sell an unnecessary addition to a normal service.

Also, im going to look at mine to see if there is any way i could have my EGR rerouted to after the cat and/or the DPF on my car to slow down the gunk buildup.

its accurate.

https://www.google.com.au/url?sa=t&r...oRIINjta8HWwh_

I’d suggest it is nigh-on impossible to convert a high pressure EGR system (which is more than likely the type used on your vehicle) to a low pressure system per the EA288 engines. You’d be better off investigating EGR-delete if it causes you problems.