Hi all,

Been a while since I've asked for mechanical advise on here!

Anyway, I've got a Golf PD150, and it's got a bit of a misfire when under heavy loads between 1.8kish - 3.5-4k. It cruises fine though.

While looking at something else earlier, my dad spotted that this pipe had been replaced - any clues as to what it is, apart from being part of the fuel system? (I have idea about non-petrol engines!)

That's the replaced bit - the flexi pipe held on with jubile clips. What is it, and what's the thing it goes into?

And while I'm at it, what are these rigid silver ones for?

And any ideas on the misfire? I'm thinking it's a fuelling issue, but not sure. Getting it scanned Wednesday though.

Sorry for all the questions, but I'm stuck here!

Thanks,

Joe

Edited 21 December, 201114 yr by TriggerFish

The rigid silver ones carry fuel, I think (the rubber pipework off the left hand side should lead to the fuel filter canister, if I'm correct, it's too cold to go and have a look).

Sorry, my bad for not being clear!

I know it comes from the fuel filter, but it's where it goes after that I don't know (so its path from drivers to passengers side).

Thanks for the response though.

Fuel feed hose and it's connected to the tandem pump. It's a dual function pump, low pressure fuel delivery, and vacuum for the brake servo. Repair looks fine, as all the high pressure stuff goes on inside each PD injector.

Three pipes, two are fuel, one is coolant.

Thanks both.

Was more wondering if that could be related to the running issues, hence being repaired, but doesn't sound like it from your description of where it goes. One more thing to cross of the 'needs attention' list.

Just 3 things left to fix now, only one of which is urgent.

Assume the yellow circled one is one of the two fuel lines as its heading in/out of the tandem pump?

have you replaced the fuel filter?

Not yet, but it was serviced 3k ago (cambelt was done too - timing issue?).

The fault scan is free, so if it points to something definitive then great, if not I'll start with the cheap/simple things and go from there I guess. Will let you know the outcome on Wednesday.

Thanks for the help.

Right. . . took it down to VAG tune in Aylesbury who have been good to me in the past, and they said they'd scan it for me.

Good news, no fault codes found!

Bad news, unable to talk to the ECU at all.

I then went via VW, who said they'd charge £42 to try their machine, even if it doesn't work. Is this likely to be throwing money away, or is VCDS likely to have issues where a VAG machine won't?

Any quick, easy things to check with the ECU comms issues, like a fuse, or anything? (I realise it's not a Fabia, but it's the same engine, just with a bigger turbo.)

Old versions of VCDS can have problems where an aftermarket headunit is connected, but I'm guessing a pro garage will be up to date with the latest "intelligent" interface from RossTech (it's a hardware issue rather than software).

I know Shark had problems connecting to my ECU to read back the Awesome map from it, but Mikko got it to work in the end. Can't remember how but I don't think it'd help you as I never had problems connecting VCDS to it anyway, it was just the lower level stuff that didn't work properly.

The only car I've had problems with VCDS on is a mates LCR which used to be flaky, but we narrowed it down to poor connections on his OBD2 port. It worked if you held it a certain way....can you connect to other modules besides the Engine module?

Standard radio/CD changer. Both of which talk fine to the Maxi-dot. They had a TT of the same age, and an A6 in that they'd been working on OK, so I'd assume it wasn't a hardware issue.

TBH, I'm not fussed if it can't be remapped/lower level stuff - just made to run properly would be nice!

Could be a dodgy port, he tried a few times with no success. They said (they were closed when they started helping me) to take it back in and they'd have a better look at it for that sort of thing. I've checked all the fuses, only the rad fan one is gone, but I can't see that stopping the ECU from communicating.

Other modules - he asked someone else's advice and they asked that, and he said they didn't work. I didn't see him doing it, but I take his word. It was also serviced recently, but the service indicator not reset, which points towards it not having worked then either. The light on the connector was flashing, if that makes any difference?

Trouble is, I don't have access to any OBD stuff, so I can't do any work on it myself (such as tracking down wiring issues etc).

Thanks for your help and time, it is appreciated!

*Edit* My dad just spoke to a friend, whose nephew works for VW, so I should be able to borrow the scanner from him soon.

Edited 21 December, 201114 yr by TriggerFish

The lights flashing can just mean the interface is powered, I think. I'm sure my lights flash (or at least light up) as soon as the cable is plugged in, even if the ignition is switched off (and therefore the ECU itself has no power so you can't connect to it). If they can't connect to any of the modules then it's sounding like a dicky port to me, they can be quite flimsy. The one on my Leon was starting to die, but I only ever had a problem with the HVAC module, it would mostly work but every so often it'd throw a fit and just fill the information boxes with gibberish.