help me please

[casper]

hi ive got a gti tdi 150bhp and i was driving along doin about 75 and the power just vanished!!!! when i pulled over and turned the car off then started it again straight away it was goin as normal and it happened again when i hit 120 mph!! i then changed the air flow meter and it went like a bullet faster than it had done since i got it! then after a few hours it lost all the power again an it hasn't come back yet! it also used to do this if it went over 3,2 in the rev range!!!! can anyone help me???? please!!!!

[Sam]

Slow down?

[casper]

its ok got plenty off speed protection and drive a rally car in my spare time! so got any help for me????

[Eshrules]

for a starter, i agree, slow down... 120mph is not a legal speed limit on any of britains public roads and can't be condoned whatsoever, regardless of whatever 'protection' or experience you claim to have.

the issue itself, sounds turbo related, when the power is dissapearing, the turbo is entering limp mode, to self preserve.

the first thing you need to do is get the car code-read, to give some direction in your search for the fault, could be sticky turbo vanes, dodgy n75 valve or a whole host of other issues aside.

more likely to be sticky turbo vanes though. get it on a vagcom/code reader and report back :beerchug:

[Sam]

its ok got plenty off speed protection and drive a rally car in my spare time! so got any help for me????

You may have protection, the people you hit wont though.

Carl has the answers ;)

He means turbo vanes though, not vines, they're grape related :D

[casper]

sound out lads! and ill try to slow down!!!! ill repost after lunch and let ye no more!!!!

[casper]

hi just got a car diagnostic check done and this is wats come up:
17664 p1256:engine coolant temp.circ.-g62
open/short to b+

18058 p1650:data bus powertrain-
missing message fr. instrument ecu

17964 p1556:charge pressure contr.-
negative deviation

17552 p1144:mass or volume air flow circ.-g70
open/short to ground

thats wats showin up!!!! any more idea's????

[Eshrules]

You may have protection, the people you hit wont though.

Carl has the answers ;)

He means turbo vanes though, not vines, they're grape related :D

thats what i said :p (love edit function ;))


hi just got a car diagnostic check done and this is wats come up:
17664 p1256:engine coolant temp.circ.-g62
open/short to b+

18058 p1650:data bus powertrain-
missing message fr. instrument ecu

17964 p1556:charge pressure contr.-
negative deviation

17552 p1144:mass or volume air flow circ.-g70
open/short to ground

thats wats showin up!!!! any more idea's????

ok, ill try to work through these, may need the help of a techie though.

17664 p1256:engine coolant temp.circ.-g62
open/short to b+ see my comments for 17964

18058 p1650:data bus powertrain-
missing message fr. instrument ecu have not got a clue about this one im afraid :o

17964 p1556:charge pressure contr.-
negative deviation - this is where the turbo has gone into limp mode, mine was 17965 which is a positive deviation, so i think this means you're experiencing an underboost situation, could be due to leaky vac hoses or the turbo sticking and not providing the level of boost the ECU is requesting.

17552 p1144:mass or volume air flow circ.-g70
open/short to ground see my comments for 17964

i could be way off here, but im thinking that the 17964 is your main issue, the two sensors showing an open/short reading, could be red herrings (in essence) arising, as a result of the underboost situation. i could be wrong, but from what i know, the turbo giving insufficient boost will cause a lack in airflow and probably a rise in engine temp... this could be why those two sensors are giving such readings. i doubt theres anything wrong with either of them.

id get that turbo off and give it a clean. check your vac hoses first of all for any leaks as this would be the easiest fix. other than that, you may be looking at cleaning your turbo/replacing with another.

take a look at this thread as well, im a little out of my depth in certain areas concerning the turbo and its functions and dont want to lead you in the wrong direction :beerchug:

CLICK HERE (http://www.vwaudiforum.co.uk/forum/showthread.php?t=8034&highlight=N75+valve)

[mk3 tdi]

the lead that plugs into the air flow sensor should be checked to see if its connected then cleaned and conncted properley