My New slow car :)

[Howard]

It would also be nigh on impossible to drive day-to-day and have terrible fuel economy

My money's on the turbo

[5lab]

It would also be nigh on impossible to drive day-to-day and have terrible fuel economy

My money's on the turbo

not necessarily, depends how the system is set up..

[Howard]

In most cases things get a bit flakey

[joshwa]

MPG seems normal-ish - when my wife drives it a fair distance she gets on average 57mpg. The car says it's overall average is 45mpg, and when I drive I can make it much lower

I will have a good look at the engine later today (and take the big plastic cover off)

[Butuz]

A boost leak is very likely (cracked intercooler or crack in any of the hotpipe/coldpipe pipework)

If the turbo was not woring at all then it would probably take about 25 seconds to get to 60.

I wouldnt have thought the computer plug in jobby would be able to diagnose a boost leak?

Butuz

[dangel]

Find someone with VAG COM and read off what the actual and requested boost levels are OR fit a boost guage (can be done temp) and see what it maxes out at. You can check for a boost leak by putting the hand brake on, opening the bonnet and putting the engine under load (i.e. revving and bringing the clutch up to biting point) with someone standing to the front (AT THE SIDE!) and listening for the air leak. This is how i solved it on mine one time (turned out to be the clip had come off the pipe connecting to the intercooler). You have to load the engine for any boost pressure to be generated (hence the handbrake to stop the car moving) and this method is an alternative to using a rolling road and usually works for major leaks.
The other thing to look for it's intercooler/intake pipes 'collapsing' under load - it's not unknown with OE parts - which will strangle the engine.

Fault codes are usually the first port of call thereafter as the VAG systems have pretty good error resolution in my experience.

One other thing - disconnect the battery for a few mins - this will reset the fuelling map in the ECU (it 'retrains'). Incidentally are you using cheap diesel?

Good luck m8.

[5lab]

MPG seems normal-ish - when my wife drives it a fair distance she gets on average 57mpg. The car says it's overall average is 45mpg, and when I drive I can make it much lower

I will have a good look at the engine later today (and take the big plastic cover off)

by the way, i'd not take what the computer says as law.. they're notoriously 'optomistic'..

[joshwa]

One other thing - disconnect the battery for a few mins - this will reset the fuelling map in the ECU (it 'retrains'). Incidentally are you using cheap diesel?

I filled up at Texaco - don't know what they're like, but I'll definitely use somewhere else next time. Will try the battery. Ta.

Is VAG-COM different to what they use at garages?

[Butuz]

Another way to check for boost leaks is to make a 50/50 mix of water and fairy liquid and then paint the soloution onto all of your boost pipes. This will then generate bubbles wherever the leak actually is. Works a treat ususally without ruining your clutch!

Butuz

[dangel]

I filled up at Texaco - don't know what they're like, but I'll definitely use somewhere else next time. Will try the battery. Ta.

Is VAG-COM different to what they use at garages?

VAG-COM is a third party product (not VW sanctioned) so yes it is different but it doing pretty much the same thing - it's software that runs on a laptop and then hooks up to the ECU via a special cable (check ebay) and allows you to read telemetry data/fault codes and even set preferences (e.g. auto lock). The fuelling thing is probably a red herring but very cheap supermarket fuel _can_ be detrimental on some cars - on yours i'd doubt it somewhat.

You don't need to load the clutch too heavily as you're not looking for 'full' boost to hear the problem of an air leak (unless it's very very small). Fairy liquid good method tho no doubt

[joshwa]

Without sounding stupid - but is it obvious which pipes are to do with the turbo? Obviously I can check all pipes that I can see, but if I knew which ones to check specifically then that might help

[dangel]

Without sounding stupid - but is it obvious which pipes are to do with the turbo? Obviously I can check all pipes that I can see, but if I knew which ones to check specifically then that might help

Easiest way is to trace them back from the intercooler which is at the front of the car - I think on yours it'll be mounted in front of the radiator. The pipes will lead from the turbo (back of the engine block exhaust manifold) to the intercooler and then to the inlet manifold (front of engine block). With the car off the pipes are quite flexible (unlike water pipes obviously) comparitively. I'm guessing the intercooler is front mounted as this is normal for TDIs - on petrol turbos side mounted intercoolers are often used. The pipes are much larger than pretty much anything else (you'll see similar sizes on air intake pipes which lead from the airbox to the turbo)

[5lab]

do you get a noticable kick up the rump at a certain revs? say around 2,000? if not, i'd say its definately tubby-related..

[[GSV]Trig]

maybe someone turned the boost down? lol
Check the boost pressure and check the intercooler, you never know it could be leaking, obscured by debris or be half full of oil....

[joshwa]

do you get a noticable kick up the rump at a certain revs? say around 2,000? if not, i'd say its definately tubby-related..

There is a very small boost / slightly noticable boost just after 2000rpm.

Here's a pic of the engine with the cover off:

bigger version here (649kb)

I will try with the washing up liquid later today.

whats the easiest way to check the boost pressure? (VAG-COM?)

[SilentDeath]

You find me the spark plugs and leads on his car and i'll buy you a Ferrari...

glow plugs need leads too

my mistake aswell but it was 3am.. noone noticed