Golf 3 GTI 2.0 ADY intermittent Power loss and stalling, please help.

**pmartin13** · 16-06-2011,07:04 PM

Hello, can somebody please help, I love my dad`s golf GTI 8V but it has an annoying fault, intermittently when pulling away from roundabouts in 3rd gear the power dissappears altogether and the car coasts to a hault, if I drop the clutch during fault state the revs drop as low as 400 / 500 rpm, then it often cuts out altogether. It sometimes hunts when idling down to 400rpm then up to 1200rpm, then back again but it usually settles down after around 30 seconds or so. It has also been known to backfire occasonally.
In general the car seems to run quite well although I dont think it runs as well as it should with so many new parts, I feel it maybe running at 85-90%.
I have changed almost every component and its cost a fortune, the list of parts are as follows, Plugs, ignition leads, distributor, coil, ECU, Fuel pump relay and ECU relay, coolant temp sensor, crank position sensor, MAF sensor, throttle body, lambda probe, full exhaust system (not including downpipe), fuel pump, fuel filter, head rebuild with full gasket set, belts etc, vacuum pipe, EGR valve stripped and cleaned, fuel pressure regulator, Injectors cleaned and checked with ASNU system, clutch kit, possibly more parts hve been changed but these are all i can think of at the moment.
Vagcom gives no DTC`s, the timing has been set up with Vagcom.

It has played up in other gears but mostly its when pulling away in 3rd traveling at around 35 to 40mph. On a 12 mile journey today it stalled 3 times and its driving me mad.
VW have no clue, they just seem to change parts and charge a fortune. I only perservere because its my dads pride and joy but I`m running out of ideas.
I am a descent mechanic but im stumped, I have visually checked the vacuum hoses as best as I can and they appear to be ok, I have also proved off that the fuel pressure line is ok. Earth point have been cleaned and checked also.

Any advice as to what to try would be greatly appriciated, thanks Paul

**pmartin13** · 19-06-2011,09:43 PM

Hi, just to let anybody that`s interested know if they have similar problems to me that I think I may have found the fault, there was a split in the vacuum hose going to the brake vacuum unit, the split was at the back of the hose so was not visible to the eye, I gave the hose a slight pull and heard it hiss slightly, upon removal this is what I found. So far the car has been ok since this faulty pipe was replaced, any furtur problems then I will let you know.
Paul NC.jpgBest of luck.

**pmartin13** · 27-06-2011,06:14 PM

Just to let people know that this dodgy pipe wasn't responsible for the running issues, as the car still dies from time to time. Somebody please help

**SammoVWT** · 28-06-2011,04:12 PM

How are the earth points? Clean? Bad earths can cause all sorts of running problems on these cars

**pmartin13** · 28-06-2011,04:34 PM

Hi, thanks for the reply. I have cleaned the main earth points under the battery and on the gearbox, also the one at the front of the engine block, So these seem fine. It always seems to fail when accelerating, once up to speed and cruising it seems ok. Thanks for your help
Paul

**SammoVWT** · 28-06-2011,04:36 PM

You said the throttle body was replaced right? Was it brand new or second hand?

I wonder if your TPS is going out of range when you press the pedal down to x position, does it matter on throttle position when accellerating or just speed?

Any difference when you unplug the lambda too?

No rough idle? Any funny temps? Coolant sensor etc, did you check that with VCDS?

Also do you get the problems when its raining/damp?

I know how frustrating fault finding can be, but might be something small missed.

**pmartin13** · 28-06-2011,04:44 PM

Hello again, the throttle body was replaced with a brand new unit, and it was set up by a very good mechanic in Nottingham who also replaced the ecu. It's not consistent and sometimes can go for days and sometimes even weeks without playing up, but on a bad day it can die 3-4 times on a relitively short trip

. The problem seems to show itself more when you ask more from the engine, ie driving quicker etc .

**SammoVWT** · 28-06-2011,04:46 PM

No power loss, just a flat cut out? like a stall? Do the dials go off?

**pmartin13** · 28-06-2011,04:49 PM

Just to add a bit more info. Speed doesn't seem to be a factor as it does it throughout the speed range. Sometimes you can cruise along at 80-90 mph for ages with no problems, slow down, drop the clutch to change down and engine would stall when the clutch is depressed. It does some funny things.
Sometimes revs will fluctuate when idling big time.

**pmartin13** · 28-06-2011,04:54 PM

It's noticeable at first when there is no power when trying to drive, the engine keeps going until the clutch is pressed then 9 times out of 10 it stalls. Lights on dash behave as they should. Tried running with temp sensor and air mass meter unplugged but no change, never tried running with lambda probe disconnected. Would you advise that i try it?