Please help!! Cold starting issue.

[Passatsport]

I have a 2008 Passat 2.0 tdi Sport, it's a BMP 16v engine.
When the engine is cold it is really difficult to start, often I'll try 3 or 4 times turning the engine until the oil pressure warning light comes on before she'll start, once warm there is no issue. I changed the glow plugs and fitted NGK CZ104, replaced the coolant temperature sensor, replaced the fuel filter, bought a code reader on eBay which found no errors, no warning lights on the dash. The car drives well although a bit lumpy at times when sitting at lights, I'm at a loss as to what else to replace, relays? The battery is fine also, so that's not the issue, any ideas???

[s2racer]

Are the glow plugs getting warm?

[Passatsport]

Hi s2racer

I don't know tbh, is it just a matter of taking one out and earthing it and turning on ignition to check?
Very rarely she will start first attempt though.

[shtu]

Passatsport said:

is it just a matter of taking one out and earthing it and turning on ignition to check?

DO NOT DO THIS.

For the minimal cost of a set of glowplugs, just change them. 99% of the time that's it fixed.

[Passatsport]

Hi shtu

Glow plugs are new NGK CZ104, replaced them a few weeks ago when problem started.

[Mr-captain]

Passatsport said:

I have a 2008 Passat 2.0 tdi Sport, it's a BMP 16v engine.
When the engine is cold it is really difficult to start, often I'll try 3 or 4 times turning the engine until the oil pressure warning light comes on before she'll start, once warm there is no issue. I changed the glow plugs and fitted NGK CZ104, replaced the coolant temperature sensor, replaced the fuel filter, bought a code reader on eBay which found no errors, no warning lights on the dash. The car drives well although a bit lumpy at times when sitting at lights, I'm at a loss as to what else to replace, relays? The battery is fine also, so that's not the issue, any ideas???

Was the eBay code reader a generic thing or VCDS (VAGCOM)? Getting a full scan done using VCDS may show what the problem is

[t400ble]

Stop chucking parts at the car, needs plugging in to a decent code reader and taking it from there.

[Passatsport]

Code reader was as info below, I created a fault by disconnecting the MAF plug and it found it straight away, easy one I suppose, but at least I know it works.

Konnwei KW808 Car CAN OBD2 Diagnostic Scanner Code Reader Tool VW Audi VS VAG405.

I guess it's back to the VW dealer with her.

[s2racer]

Test for voltage at the glow plugs, they are only 12v. Did you connect the new ones back up and no fuses blown?

[Passatsport]

Hi s2racer

No blown fuses, I'll borrow a multimeter from work and check them, I have a cc also and was going to swap the relays over, if they're compatible and more importantly if I can find them!

[Mr-captain]

Passatsport said:

Code reader was as info below, I created a fault by disconnecting the MAF plug and it found it straight away, easy one I suppose, but at least I know it works.

Konnwei KW808 Car CAN OBD2 Diagnostic Scanner Code Reader Tool VW Audi VS VAG405.

I guess it's back to the VW dealer with her.

You really need to get it connected to VCDS/Vagcom. It's not just a code reader but will also allow you to run tests, and check sensor values amongst other things. It will often show things a generic code reader can't. Any VAG specialist should be able to look for you, there is no need to go to a dealer if you don't want to.

[Dr G]

When it's running does the exhaust smell of fuel?

[Passatsport]

Hi Dr G

Yeah it stinks when running.

[Passatsport]

Ok chaps I'm kinda realising that these plugs are not getting any power whatsoever, I did notice last night when checking the fuse box in the engine compartment that one of the cable connections coming out of the box, 50 amp, was quite corroded. I took it off and cleaned it a bit and to my utter surprise she started first push of the key this morning, so i'll give it a good clean with light sand paper later and add some grease before reconnecting.
Does this sound like a plan??

[s2racer]

I would just clean it. You can use vaseline to prevent future corrosion but not much is needed

Sounds like a result!

[Passatsport]

Thanks for help guys, I will let you know how it goes in a few days.

[Dr G]

BMP is a PD, yes?

If so worth checking if it has had or needs the injector recall.

Tandem pump failure mixes fuel and oil which can explain both poor starting and the smell.

[Passatsport]

Hi Dr G

Thanks for that info, I will def check with my local dealer regarding this 'recall' as she does indeed smell very oily when running.

[Dr G]

Ask they check for oil/fuel contamination also

[Passatsport]

Will do Dr G, thanks.