2.0 TDI (BKD Engine) Cold start problem...Getting frustrated now!

[doylebros]

Your's is the easier of the two.

Remove the T25 bolts - "don't disconnect any pipes" - separate from the filter (to allow seal change)!

Notice how much fuel is in the housing (this is what empties) if that housing your fitting the seal too has a defective valve!

When refitting tighten each bolt evenly a "bit at a time and opposite position".

If the filter is black you have a problem with oil passing on the tandem pump.

[andybon]

Just checked the fuel filter and this was how much fuel was in when i opened it up.



And this was the colour of the filter, Only a few months old. Seemed to have oil in it when i ran my finger in it

[doylebros]

Level should of been above the filter by 15 mm ish when put in the housing.

How many miles since the change not time is the issue?

[andybon]

The pic showing the level was took just as I lifted the lid off.

Probably looking at around 1500 miles since it was last changed.

[Trekmeister]

Your's is the easier of the two.


Notice how much fuel is in the housing (this is what empties) if that housing your fitting the seal too has a defective valve!

Which valve could be defective?

[apples12]

Injector seals...

The blackening of the fuel filter is gases blowing back into the fuel and clogging the filter.

Had same problem on my 1.9pd

Once the injectors were replaced after cleaning, new seals and torqued down, its been flawless for the last 35k

Injector specialist told me it was bad fuel,apparently supermarket fuel is good for causing this.

[Paul_zx6r]

I had a similar problem,  I had a dti test done basically my injectors set up and they were way it, it helped a lot but its still a bit lumpy on start up

[doylebros]

The pic showing the level was took just as I lifted the lid off.

Probably looking at around 1500 miles since it was last changed.

Your photos show:-

The level you would expect if everything is working correctly so if the vehicle hasn't been started there's nothing wrong with the housing and valves!

However, the picture of the filter shows a rather black filter for so few miles!

This black indicates the oil seal behind the tandem pump is failing which contaminates the fuel lift pump in the tank - next stage is to confirm the condition of the pump in the tank by removing the rear seat to access the pump.

Just read Apples12 post and as he says, that is common but google both for further comments.

But as I originally said the fuel housing was my problem!

[doylebros]

Your's is the easier of the two.


Notice how much fuel is in the housing (this is what empties) if that housing your fitting the seal too has a defective valve!

Which valve could be defective?

The fuel filter head the part with the pipework attached as show in the photos!

[andybon]

So the next place to look is the fuel pump in the tank and check for oil there too?

I take it the seal in question is the one between the actual pump and the engine block, if so are these cheap to buy/easyish to replace by myself or is it a case of going tho a garage/dealer to get it done?

[doylebros]

Yes, if that was the filter housing level from cold (as per the photo)!

However, that wouldn't normally just give one fault, if the tank pump is contaminated, you would get other symptoms - poor idle, light misfire etc.

Air in the system or lazy pump would and does give your fault, but it's more like a brown sludge on the filter than just blackening of the filter.

[andybon]

That level was after been sat for 3 hours from last been tried (started then stopped when it started correctly)

So it's possibly a new pump that's needed?

Really am loosing faith with the car, been tempted to just trade it in all day and be done with it :(

[doylebros]

It's not easy when you lose faith in your motor but more testes are needed before parting with any money!

Tomorrow, before starting cycle the ignition key three times to position 2 counting to five then on the four go start the vehicle and see if that improves it - (it gives the tank pump more time and chances to purge air if that's the issue)!

So until tomorrow!

[andybon]

I will give that a go then go from there! Hopefully I will get to the bottom of it somehow!

[doylebros]

When you changed the seal today was there any water droplets or muck in the bottom of the filter housing?

Also when you had the timing checked with VCDS did they do a full scan or have you got access to VCDS Tool?