Odd loss of power Mk3 Tdi

[sparkie]

No boost gauge fitted, sadly, yet another project! I am not sure whether it smokes when the boost is suddenly lost, logic would suggest that unburnt fuel would suddenly exit the exhaust, but is isn't noticeable when driving. So far I've replaced 3 metres of rubber tubing associated with the turbo, the red and black lines attached to the N75 valve, and the line going to the EMS under the windscreen. I tried to replaced the blue N75 valve one, but the pipe disappears down below the turbo-charger into a place I couldn't see, let alone get to! So I didn't bother. That's about half the piping in the engine bay, some of it was so shot (or eaten by rats) that I am surprised it has been working this well! The line to the EMS was completely shredded!

I haven;t had a long, hot run in it yet to tell whether things have improved....

[lynnos]

Hello, sad to hear your'e still having trouble. Don't overlook the fact that the engine may be starving for fuel. I had a Series 1 Golf diesel that ran out of puff on hills due to low fuel flow from a near blocked strainer on the tank pick up. I'm not sure if your later Ser. 3 has the same thing but it was accessed by taking out the back seat and removing the fuel gauge sender and hooking out the strainer with a stout wire. It had a fine screen and was chocked with slimy fuel bug. My G1 GLD had a clear line to the fuel/injector pump and when it played up badly I pulled over quickly and looked under the bonnet to see the fuel line was very airated which lead me to looking back down the line. It had a short hose from the tank to the body pipe and after pulling that off hardly any fuel came out so hence looking in the tank.

[lynnos]

As a PS to above, Have a look on the website www.partsbase.org/ If you don't know about it already. Pick out your model and year and go to the engine section and there is a whole lot of drawings to show the appropriate vacuum hoses etc. You need to roll down a bit to get to exhaust gas recirculation parts.

[gldgti]

Hello, sad to hear your'e still having trouble. Don't overlook the fact that the engine may be starving for fuel. I had a Series 1 Golf diesel that ran out of puff on hills due to low fuel flow from a near blocked strainer on the tank pick up. I'm not sure if your later Ser. 3 has the same thing but it was accessed by taking out the back seat and removing the fuel gauge sender and hooking out the strainer with a stout wire. It had a fine screen and was chocked with slimy fuel bug. My G1 GLD had a clear line to the fuel/injector pump and when it played up badly I pulled over quickly and looked under the bonnet to see the fuel line was very airated which lead me to looking back down the line. It had a short hose from the tank to the body pipe and after pulling that off hardly any fuel came out so hence looking in the tank.

Thats a very good point, the symptoms described could definitely be fuel starvation aswell.

[sparkie]

I've discounted fuel starvation because it's not all the time, and because the tank and lines were all cleaned out when I found algae in the tank, but thanks, I'll double-check and sort out the fuel sender which is currently making the fuel gauge jerk around!

[lynnos]

Just harking back to someone above, is there a lot of black smoke out the back when you lose power. Black smoke is partly burnt fuel and is a sign of many things. Next time you are losing power and have your foot down you should see black smoke. If there is fuel starving there won't be any smoke. Interesting about your gauge being inconsistent. It would be good to have a good look in the tank as there may be rubbish intermittently interfering with it and the pickup. Maybe a big lump of bug slime. Which year model and engine code do you have?

[papa600]

Be careful if its anything like mine it can be early signs of the fuel pump about to kill itself sending metal shards through your injectors.
It wont show on error codes even on the Mk6's

Just my experience see http://www.vwwatercooled.com/forums/...tle-99747.html

Disregard the loud whistle that hasnt even been addressed yet under a 5 grand repair bill...I noticed the car acting odd for a few weeks beforhand thought it was something to do with the whistle but ended up being my fuel pump dieing...

[Ryeman]

Be careful if its anything like mine it can be early signs of the fuel pump about to kill itself sending metal shards through your injectors.
It wont show on error codes even on the Mk6's

Just my experience see http://www.vwwatercooled.com/forums/...tle-99747.html

Disregard the loud whistle that hasnt even been addressed yet under a 5 grand repair bill...I noticed the car acting odd for a few weeks beforhand thought it was something to do with the whistle but ended up being my fuel pump dieing...

papa600
is yours a Common Rail (CR) or PD Pump Duse?

[papa600]

papa600
is yours a Common Rail (CR) or PD Pump Duse?

Good questions its a CR which would make my comment above useless on the Mk3?

[gldgti]

Yes, they are nothing alike

[Ryeman]

Just that I started a CR Problems specific thread and no one has responded .....giving the impression they're bullet proof.
I've asked mods to move your problem to the CR specific thread so we can compare issues on this later engine rather than constant confusion as to which engine series we're dealing with.
It would make the ? as to whether the CR is a more reliable engine than the PD version........like a poll.


Sent from my iPad using Tapatalk

[G60ING]

If you want help trouble shooting TDI engines then you should visit the TDIclub forums. More knowledge than you can shake a stick at.

[sparkie]

I've been on TDIclub forums, I'll give it another go, but I couldn't find anything.

Just for the record vagcat says the part number for the N75 solenoid is 1H0906627
pressure converter / use if required:
EPW-ABGAS 046 130 405; 046 131 887; 052 129 734

[G60ING]

Post up the link, I'll chime in and see if a few of the tdi geeks can chime in.

[G60ING]

Odd loss of power Mk3 Tdi

N75 Wastegate Solenoid Valve (A3)(B4) - 028906283F - IDParts.com

N75 Wastegate Solenoid Valve
$51.95

OE Part Number: 028906283F