So I m after a bit of help. I parked my car up last night running fine, no problems at all.

 

This morning, I've gone to use it and noticed as soon as I started it up it was loud. I mean loud as in a loud popping coming from the exhaust. Then I noticed the eml was on. I also noticed when I was revving it there was no turbo spool at all.

 

I've got an obd2 Bluetooth scanner which I used to read the fault code which came back as P0236 powertrain and then said something about a circuit "A" being out of range. Sorry I can't remember the exact description of the code as it was a few hours ago but it was along those lines.

 

I have done a quick Google which is pointing me towards the map sensor.

 

Any ideas?

MAP sensor, wiring, boost leak or knackered turbo, take your pick. Hard to be more accurate with a generic code from a cack dongle.

Would I not have noticed the turbo failing/boost leak before I parked it up though. This fault seems to have appeared over night

You'll have to investigate, I've never had a car go wrong while it was parked up overnight, let us know what you find.

I'll have a look and hope I find something obvious like a boost leak or something. My car is modified and so comes with a pd150 hybrid turbo and fmic with 4 bar map sensor, just incase this makes a difference?

Right I've had a look at the car this morning. All though I'm no mechanic I couldn't see any boost leaks or broken pipe work. I started the car up - still have this loud exhaust note and no boost. I left the engine running while I had a look around and let it get up to temperature.

 

At this point I decided to clear the fault code and hey presto the exhaust note quietened and the turbo came back. 

 

I took it for a drive around the block and although it was boosting it felt a bit lacking and wasn't picking up as quick as it usually does from low revs.

 

I pulled back up on my drive to be greeted with the engine management light again but the turbo is still on at this point. Done a scan and same code as before P0236 Powertrain - turbo/super charger boost sensor "A" circuit range/performance.

 

Any thoughts?

Edited 19 March, 20179 yr by daz_vrs

I think your VNT is sticking, hence the change in exhaust tone.

2 hours ago, sepulchrave said:

I think your VNT is sticking, hence the change in exhaust tone.

ok thanks for the advice.

 

ive googled this problem and seen a few videos of people using oven cleaner to free up the vanes on the turbo. it shows spraying oven cleaner into the exhaust side of the turbo while moving the actuator up and down.

 

ive now been out and checked my actuator which I could only move a few mm. its so hard to press like its got the strongest spring in the world in there, so now I'm thinking your right about the vnt sticking.

 

ill probs just take it to my local indi to get this done as ill probs cause more problems than fix any if I try to do it with my mechanical knowledge.

 

ok so after going back out and getting the actuator to move I decided to take it back out for a drive to see if this made any difference. first thought was yes, the car did feel better but on returning to the house was greeted with the same fault code as before but now I have another pending fault code

 

P0101 - powertrain mass or volume air flow circuit range/performance problem

 

is this related and still looking like sticking vnt?

Edited 19 March, 20179 yr by daz_vrs

just read this......looks like the cam :(  http://forums.tdiclub.com/showthread.php?t=467185

 

ive probably been losing power gradually and not noticed it. the car has occasionally sounded loud from the exhaust and tappy from the engine on first start up but its always gone away once warmed up.

 

the cams probably being showing signs of wear for a while and ive not known it. the cars on 155k now so I'm not suprised

ok thought id update this thread. 

 

Ive had a go with the Mr Muscle cleaner on the exhaust side of the turbo as to unstick the vanes. All went well and I had the actuator moving easily. After was all done I took the car out and my first impressions were that it was fixed. Just pottering around the doors to get the engine warmed up a bit it felt a lot better. But as soon as I could take it to the redline as per the instructions of the turbo clean it held back and loads of black smoke. I drove home and was greeted with the same fault code and limp mode.

 

Today I thought id have a look and see what the map and maf readings were through my torque pro app and this is where it gets interesting......

 

When in limp mode and turbo turned off, at idle the boost is at vacuum of 0.1 and the intake manifold pressure is at 14.7 psi. Once I clear the fault code hence turning the turbo back on at idle the boost is showing 11 psi and intake manifold pressure of 25.7 psi. 

 

So am I right thinking this could be a faulty actuator, n75 or vacuum leak?

Yes, it may be overboosting and dropping into limp mode, it seems excessive to have 0.75 bar of boost at idle although I don't know what the specs. are for it.

hybrid pd150, 210bhp 320lbs/ft

7 minutes ago, daz_vrs said:

hybrid pd150, 210bhp 320lbs/ft

 

I meant the mapped boost specs. not the Maccy D's car park specs.

oops lol, couldn't tell them sorry......

Ok I thought I'd keep this thread up to date with how I'm getting on with this fault. I've narrowed the problem down to either faulty actuator, vacuum leak or sticking vnt (even after the mr muscle clean). 

 

I've since found out a way of checking the vacuum system and actuator travel by removing the vacuum line from the ball at the front of the engine and while the enine is running block the line with my finger going to the vacuum box. This in turn makes the actuator move full travel in and when released let's it travel all the Wat out. Just by blocking and unblocking this line gives me full movement of the actuator without having to rev the engine. 

 

First thing I did notice is that the car now had 19.4 psi at idle with was way worse than before and when I blocked the line the actuator moves in but got stuck for a second and stayed there when the vacuum line was unblocked for a second before shooting back out. This has me thinking that everything is working as it should be except for the vanes on the turbo which are sticking still stopping the turbo closing off. 

 

Looks like I need to try another turbo clean as the other one I did didn't work. I'll keep this thread updated with how I get on.

Just to be completely clear, apologies if you're already aware of this, but the way the ECU measures boost means it uses the MAP sensor which means Manifold Absolute Pressure, this therefore includes normal atmospheric pressure which is 14.5 PSI (1 Bar or 1 ATM), therefore when we talk about boost, this is the amount of pressure supplied by the turbo over and above 1 ATM, this is why the standard MAP sensor is rated 3 Bar and if your hybrid is boosting above 2 Bar peak you need a 4 Bar MAP sensor because the headroom needed for it includes the standard 1 Bar or 1 ATM when there is no boost at all.

Therefore your MAP sensor will read ~1 Bar (14.5 PSI) even when the engine is not riunning.

Yeah sorry I should have stated it was showing 19 psi on the boost guage part of the app with around 32 psi intake pressure.

 

The reason I was only stating the boost from the boost gauge was because at idle I was under the impression it was supposed to be at vacuum. It does show vacuum and 14.7 psi intake pressure when in limp mode so this is why I was ruling out the map sensor, but now I'm not sure as surely at idle the turbo can't be producing that amount of boost?

Edited 8 April, 20179 yr by daz_vrs

No, it shouldn't be possible, either the app. is wrong or the MAP sensor is donald.

Well there is deffo something up with the car so new map sensor it is

Ok so hopefully I'm getting somewhere with this fault. I removed the front bumper to gain access to the map sensor to be greater with a broken wire right at the plug. This was caused by the wires being too tight against the plug itself as when the fmic was installed the new map sensor location was a bit of a stretch for the wires.

 

I also removed the sensor itself which was clogged up with thick black gunge. I've gave this a clean with electrical contact cleaner and an now in the process of putting a new plug on with longer wires.

 

I've found this and was wondering if anyone knew if this is what I need?

http://m.ebay.co.uk/itm/322474934776?_mwBanner=1

Ok I've replaced the map sensor plug using the item listed above. I'm now getting a reading of 3psi boost, 17.5 psi intake pressure at idle and no movement from there. When I drive the car it feels back to normal and I can hear the turbo loud and clear. Only problem now is I'm getting low boost fault as it's only reading 3 psi boost.

 

My plan now is to replace the map sensor. This is where I need some advice. I've taken the numbers down from the map sensor that's in my car and are as follows

0 281 002 401

038 906 051 c

 

I've searched the Internet and keep getting 3 bar map sensors with this number? As mine is a pd150 hybrid running over 200bhp I was certain I would have a 4 bar map sensor?

 

Am I missing something? Could the fact it's mapped with a dastek ecu have anything to do with it?

 

Any help welcome

Looks like I only need a 3 bar map sensor so I've ordered one the same as this broken one and hope this sorts the problem

Ok thought I'd wrap this thread up. Car fixed with new map sensor.