Volkswagen Transporter Shuttle 1.9 TDi PD 102 T30 - VW T5, fault code P0236, loss of power advice p

Honest John Back Room » Technical matters
What is life like with your car? Let us know and win £500 in John Lewis vouchers | No thanks
View Threaded
Tue 4 Feb 2020 16:16
Volkswagen Transporter Shuttle 1.9 TDi PD 102 T30 - VW T5, fault code P0236, loss of power advice p - Martyn Newman

Hi all,

I'm after some advice please. First time poster here.

I own the above vehicle, and a little while ago whilst driving home I noticed a distinct lack of power. I struggled to get to 30mph travelling up a modest hill. I got home, and the next time I used the vehicle the engine management light came on and the same symptom persisted - a huge loss of power.

I bought a little £15 bluetooth ODBII adapter and downloaded the app, which displayed the following code: P0236 Turbocharger Boost Sensor A Circuit Range/Performance.

So far, I have tried the following (I am no mechanic, all the things I've tried have been as a result of google searches and reading on forums):

- Cleaned the air filter

- Removed and cleaned the MAF sensor, and the housing.

- Checked the wires leading from the MAF sensor

- Removed and cleaned the EGR valve

- Removed and cleaned the boost pressure (MAP) sensor

- Sprayed a can of Wynns turbo cleaner through the air intake hose (immediately after the MAF sensor)

- Sprayed a can of Wynns EGR cleaner through the air intake hose, as above.

- Checked the air hoses that I can see / get to easily. I'm convinced I can hear a hissing sound when standing over the engine with it running, but it could be anything.

It may sound strange, but the van 'feels' like it's performance has improved slightly, but unfortunately the symptom persists. I've used the OBD to reset the fault code at several steps above, but at no point has the power returned. I've driven the van a few miles after some of the steps, but I struggle to get it above 3000rpm, above 40-50 on the level, or 20-30 uphill.

Each time the engine light has come back on, the OBD code is the same, P0236.

My thoughts so far are to replace the MAF and / or MAP sensors, somehow check the pipes for leaks (smoke machine? Vape?), and bottom of the list is to take it to the garage.

It's an old van and has swallowed £1,000s over the years, and I'm trying to keep the cost of this as low as possible. So far I've spent about £20 on the cans of Wynns stuff.

Does anybody have any advice or suggestions?

Thanks in advance.

Reply | Report as offensive | Link
Tue 4 Feb 2020 16:53
Volkswagen Transporter Shuttle 1.9 TDi PD 102 T30 - VW T5, fault code P0236, loss of power advice p - galileo

the symptoms suggest the turbo is not operating as it should, the actuator that moves the wastegate or variable vanes may be faulty, some of these have a diaphragm which may have failed, even though the fault code suggests an electrical fault.

If your engine has the variable vanes these are prone to sticking due to carbon build up.

Does the turbo rotor move freely? If you take the air inlet connection off you should be able to see and touch ( with engine off!) the compressor wheel. This should be spinning even on tickover.

I'd suggest having a more complete diagnosis, if there is a Diesel service agent near you they should be cheaper than a VW agent and more likely to know what the problem is.

Edited by galileo on 04/02/2020 at 16:54

Reply | Report as offensive | Link

Looking for a garage you can trust? Honest John's Good Garage Guide has thousands of reader recommended garages, plus how-to guides and tips on servicing.

The Good Garage Guide

From which small car to buy at which price point to the best UK-built cars, our Top 10s have the lot. Click now for your shortlist.

Unsure of what to buy? Our Top 10s are here to help you....