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Model specific boards => Golf mk4 => Golf mk4 TDI => Topic started by: mrapoc on 05 January 2012, 21:32

Title: A few TDI Problems - What to try next
Post by: mrapoc on 05 January 2012, 21:32
Hello!

The suspect is a 1.9 gttdi AJM 115 @ 160k on the clock.

What is the issue?


What have I done so far?


Any help or suggestions would be very gratefully accepted.
Its a lovely car but the main issue is only getting 100 miles to £20-£25 and thats driving steadily!
Title: Re: A few TDI Problems - What to try next
Post by: littco on 05 January 2012, 21:35
Sounds like a boost/ vacuum leak.

Check all connectors around the system and vacuum pipes.
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 05 January 2012, 21:38
Cheers mate. I have changed 3/4 of the vacuum pipes already. Not sure if the turbo should have a 3mm pipe or 4mm pipe going to it. So i havent done that yet.

Would it be an idea to ask a local garage to smoke test it? How much should I expect this to cost. Don't want this car to be any more of a money eating bottomless pit!

 :laugh: :laugh: :laugh:
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 08 January 2012, 20:33
Drove up the m54 today. Stuck to 70mph all the way and managed to get 45mpg. Surely I can/should be getting more?
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 09 January 2012, 22:24
I'm getting a flat spot/shuddering at about 2k revs now too  :sick:
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 18 January 2012, 23:08
Cleaned the intercooler and noticed the MAP sensor has been messed with before...well. It had silicon sealant all over it. Also one of the screws looks badly rounded..If its anything to go by my MAF (non genuine) could this possibly be causing bad mpg? Worth prying off all the silicon and tapping the screw out to check?

 

I've changed the thermostat and temp sender (to a green one) anyway :)
Title: Re: A few TDI Problems - What to try next
Post by: sprout99 on 19 January 2012, 07:41
map sensor could be a problem.

on a past car that was causing me loss of power at about 2000 revs
Title: Re: A few TDI Problems - What to try next
Post by: scarr89 on 19 January 2012, 18:00
map sensor could be a problem.

on a past car that was causing me loss of power at about 2000 revs

+1

I cleaned mine and my flat spot, which was around 2500, disappeared.  :smiley: This will take an hour tops, real easy fix if this is your issue.
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 19 January 2012, 23:54
Cool.

I've changed my MAF already and this helped.

Now I am experiencing loss of power at 2k/mpg issues too so i will check out my MAP too if this may be the case :)
Title: Re: A few TDI Problems - What to try next
Post by: EsSeX dAn on 31 January 2012, 23:37
when ws it last serviced fella? how long have you had the car aswell? could be a timing issur
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 01 February 2012, 16:02
Hey.

I serviced it about 5 months ago. Havent had decent mpg since owning it tbh. I have a feeling that the map on the intercooler/boost leak may be what im looking for...
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 15 February 2012, 21:09
Right an update

Changed the MAP sensor on the intercooler (thrust) and PSI adjusted my actuator as it was overboosting (still is tho..)

Also had it mapped to see if it was a bad map. Hard to say if its any better.

Only thing I can think of now is if the manifold is blocked up (would a clogged manifold really fook up mpg?)

Also maybe something more serious like loss of compression, i dunno.

The way i describe it is, once i get to a speed like 70, i should be able to hold that speed, but it starts falling in speed once i get a decent mpg. To hold it I have to accelerate back up, hence losing the mpg
Title: Re: A few TDI Problems - What to try next
Post by: scarr89 on 15 February 2012, 21:48
Wow, very strange symptoms...Really hope you get it sorted mate. Scanned it for any codes? Perhaps do some date logging while running the car, see what reading your getting on all variables?  :sad:
Title: Re: A few TDI Problems - What to try next
Post by: kennedyuk2001 on 15 February 2012, 23:37
If your car is struggling to maintain 70 without giving a little extra then maybe you have a sticky caliper?
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 16 February 2012, 01:25
Wheel seemed to spin quite freely. But yeh it is almost like it needs that extra acceleration as it won't just hold it there.

No faults over than when i get it to overboost (full throttle)

MAF is ok. Boost is ok (apart from full throttle). Best way to check for sticky caliper?
Title: Re: A few TDI Problems - What to try next
Post by: kennedyuk2001 on 16 February 2012, 08:38
Check all four wheels, get it in air, push brake then spin a wheel, should roll fairly easy and not have much resistance and roll to a steady stop not too suddenly. Check all wheels, as could also be sticking handshake issue.
Title: Re: A few TDI Problems - What to try next
Post by: tdi_blu on 17 February 2012, 10:06
Hi Im not that clued up on engines etc but I thought I would mention my fault that I had as at least you could check it.My own car not to long ago had issues where it was crap on mpg and losing power and eventually as things got worse the car would cut out completly.I changed all sorts of things and we could not find the problem and at one point I just felt like setting fire to it  :grin: Anyway by sheer chance when it was in the garage a vw tech was also there picking up a car and asked what the problem was we explained and he went straight to the back seat had a look under at the fuel pump and explained that the in and out on the pump was the wrong way round and the car was being fed fuel only through the drip rail is it something like that.Apparantly its a very common fault on mk4 golfs and it happens why its being built in the factory whats mad really is that the cars can run perfect for years but then at random start to play up.Could well have nothing to do with your fault but I just thought its worth a mention,stick with it you will get to it in the end  :wink:
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 20 February 2012, 17:57
Fuel pump is correct but cheers mate :)

I have tried wheels but ill try again after pressing brake pedal
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 21 February 2012, 01:15
Blocked cat or timing maybe  :laugh: :angry:
Title: Re: A few TDI Problems - What to try next
Post by: sprout99 on 21 February 2012, 11:55
is your EGR stuck open?
Title: Re: A few TDI Problems - What to try next
Post by: mrapoc on 21 February 2012, 12:13
How would I find out?
Title: Re: A few TDI Problems - What to try next
Post by: sprout99 on 22 February 2012, 07:51
pull pipe to intercooler off and have a look inside. The valve should open when car is idleing and close when revving