[K2edg]

Hi all.

I ahve been searching hard for a few days now trying to figure out what was going on with my Passat and its lack of power, i've just came across the Dignostic write up's on here which has really helped (Thanks) so i thought i'd join up seeings as this is where all the Vag Guru's hang out

Thanks again guys, Wish me luck on my Turbo vain clean up (hope it cures my limp mode issues) :ugh

 

[Seatman]

Is it lacking power or is the pwer suddenly going then coming back when you restart the engine?

welcometomyturbodies

 

[K2edg]

TBH its a bit of both, the problem started off where the power was Intermittent (one day would struggle to pick up and no real go in it then the next day it would drive great) this went on for a few weeks until it started to loose all its power whilst driving (and yes if i turn it off then back on it ran fine again).

I have since fitted a new Cam belt, changed the Maf Sensor and N75 but it has not really helped (felt slightly more consistent for a few days but went back to how it was soon after)

I did quite allot of reading up and came across the Turbo Vain issue with this engine, so i had a bit of a play with the turbo/Actuator. When the car is started from cold the Actuator rod moves about half way then stops, if i get hold of it before the turbo gets too hot and help it a bit then it will close completely (bit like its sticking) so I think a Good clean of the Turbo should help.

Thing is even though its going into Limp mode (or what I think is limp mode) the engine light doesn’t come on and i haven’t been fortunate to be in the right place at the right time so I could get home with it in the limp mode to check it before i turn it off (always seems to happen when I’m miles from home)

I think if the Turbo turns out to be ok the next on the list would have to be the Map Sensor, Unfortunately its a bit of an Educated guess as I don’t have a VCDS Scanner to check its values but it looks like the original one from the factory and the symptoms would be about right if it was giving a bad signal.

 

[K2edg]

Out of interest, How easy should the Actuator be to move the Turbo’s vain assembly? I have just read if I connect a pipe up to it and suck hard it should move 10mm? (mine doesn’t move at all)

 

[K2edg]

Bit of an update.

Took the Turbo and inlet off today, the Vails in the turbo where quite badly clogged up and took quite a bit of cleaning to get working smoothly again. The Inlet was the same story, it was Caked in black oily carbon so that also got a good cleaning.

its all back together now and it seems to have got most of its low end power back but it still feels like its holding back quite bad.

Would you say its time to buy a VCDS Scanner and see if all the sensors are working as they should be? one thing i did just notice is the water temp gauge inside has stopped working? not sure how long its been like that? would that cause this lack of power problem?

 

[chittychittybangbang]

The water temp gauge could be a bad coolant temp sensor, common problem. The sensor is on left side (while sitting in car) of cyl head coolant flange. If you have VCDS you can verify the temp reading by looking at it in the engine measuring blocks.

You said you sucked on the hose to the VNT actuator, that will not work unless (insert obscene joke here). You need a vacuum pump because of the pressure required. Since you already took the turbo off, the vanes should have no resistance with the VNT actuator disconnected. With it connected you should only feel the spring inside the VNT.

 

[K2edg]

I think the Turbo vains are working as they should now, with the Actuator off it's now easy to move and smooth (no snags), while it was off i conected the Actuator up to a Mityvac Vacuum pump and it worked fine (left it for a few minutes nted vacuum and there was no leak)

So now i'm happy the Turbo is working fine and the Inlet/EGR is clean and clear i guess i need to be looking at buying a VCDS Scanner (where is the best place to get hold of one?)

Would the water temp sensor be causing these sorts of problems? and is it the same one thats used for the ecu and Clocks?

 

[K2edg]

Ok, Just fixed the water temp sensor, got a new sensor and stuck it in and worked first time (Thanks for that)

I haven't been out in it yet but i'll let you know if its made a difference.

I've now got the two biggest question marks out the way so all in all A good days work

 

[stroud2010]

chitty:
"that will not work unless (insert obscene joke here)."

Me:
I love reading these forum posts! :laugh::laugh::laugh:

i'm not making fun of anyone here
its just funny =]

 

[K2edg]

Yeh when i typed it i was fully expecting some comment

 

[K2edg]

Just been out in my car and today’s endeavours has not fixed it, still no power and it wont rev past 3500rpm in gear.

I can hear the Turbo spooling up and it starts to go then runs out of puff, its like its running 2psi of boost pressure....

 

[K2edg]

Been reading this morning and decided the MAF seemed to fit the bill for the lack of power asuming the Sticking Turbo vains caused my limp mode to keep going off? so i tried unplugging it and tbh it made little to no diffrence pluged in or not so does this mean the Maf is faulty?

The Odd thing is i replaced it about a month ago? (maybe a bad replacement or bad wiring??) but the way i read the how too guide there should be a noticable lack of power with it unplugged whilst driving? and there isn't (in fact it may be marginaly better at higher revs) also runs better with the air filter out?

Can the Maf be tested via Multimeter?

 

[K2edg]

I think we have a winner, took the old Maf sensor apart and cleaned it with some brake cleaner (was quite grubby and had oil on the element) then put it on the car and its running MUCH better, pulls well thought the rev range and actually feels pokey in first and second very happy.

So the big question is do i go and buy a new Genuine VAG one or do i leave this and see how it goes?

 

[chittychittybangbang]

:thumbsup
Fix until broken? If it's running well now, I wouldn't touch it.

 

[K2edg]

Yeh maybe leave it now, if it starts to play up again i'll change it.