None starting caddy 2007 2L sdi

[Edfirst]

Hi folks, hope some of you super tech heads can assist me with my dilemma.

Had nothing but trouble since I first got this van with injector failure then a stripped clamp bolt causing seals to leak and fill engine with diesel whilst running like a pig, got all that sorted and was running great....well for a week at least, then the ABS light and a flashing red exclamation on dash with some random bongs from the dash after a few seconds.

Took it in for the codes scanned by the local garage and they claimed that they could not get coms with the van, strange as only the day before I reset the engine MIL light to clear the injector related codes and all was ok then. Now I cannot connect and then the day after it simply stopped on me and refused to start, here is what I have checked since; Took the tank out thinking that the in tank pump had gone duff, tested and that was fine, then hunted for the relay (which still not convinced have found) somewhere on web stating that it was relay 449, changed this but still no live to the tank pump, so tapped into the live pump feed with a direct connection to the battery and the pump works and pressures up but the engine still wont start, suspecting the ECU I took the return and feed pipes from the fuel filter and primed them into a container with an inline filter to the feed and she started straight away.....hum??

suspected a blocked line so connected airline to the released lines and the blew clear......now here is the weird thing with everything reconnected except the fuel filter return to the tank and a clear piece of tube into a tub I tried to see if indeed fuel was bypassing to return when pump was run (by me tapping into the feed again as still no joy at the key) and nothing, so I disconnected the feed to the engine pump and got showered in diesel as the pump had pressurised everything...hum....am I right in asking that fuel once pressurised should stop the pump under normal operation, and why is fuel not being returned to tank otherwise whilst forcing the pump to work. At my whit's end with this van now int

[Guest 2]

I would be getting a scan with VCDS or at a push, VW to get a proper diagnosis.

Have a look on the map in my signature, if you see anyone let me know and I'll bring their attention to this thread.

[Edfirst]

Wow...hi Chris, thanks for the speedy reply, but I have VCDS and was able to connect and read etc just fine, up until it went in for MOT and I asked whilst there to read the ABS code issue for me, could have done myself but thought whilst in garage let them do, they stated that they couldn't connect to the van or should I say communicate with it, so when I got it back I tested with mine and I too get an error when connecting now....I did check the map thing and there does appear to be two close to me.....the Blackburn one and the what looks like Skipton....just has coordinates when try to get directions......will see if anyone can point any other possible directions....cheers. Ed

[Guest 2]

Try disconnecting the battery and leaving it for 30 mins and try and rescan.

Which module can vcds not communicate with?

[Edfirst]

Have to say I have not tried that, what does this do reset the system?? I will do that in the morning before I go to work then when I come home for dinner I will reconnect and try to scan again. I cannot remember the exact error as I have been at this now for almost three weeks, but it was something like cannot find vehicle or something like that....will post here what it says when I do again after the battery trick.....cheers. Ed

[Edfirst]

Well here is an update, I did the battery off for half a day trick and guess what I can scan the van again now, only error code shown was P0600, which I reset and the MIL light went out and stayed. But first the good news, after tapping into the live feed for the fuel pump and trying to start this time she fired straight away, BUT the minute I took the wire from the battery within ten minutes of revving at 1500 she stalled and will not start, checked the fuel lines and yep no diesel, so something is stopping the power to the fuel pump. Am stumped now, nothing from VCDS does anyone know if these have a crash switch that stops the pump? if so where is it likely to be? will call the ********-n-dealers in the morning with the chassis no and see if they can shed light on my wows.....:-( cheers.....Ed