VW Caddy 2005 Starting Problems

[connor_perth]

Hello there,

I bought a second hand Caddy 2005 SDI back in October (2022). It ran perfectly for about a month and half when suddenly one evening it would not start. The engine was cranking but no start. I thought it might have been a dead battery for I noticed one of the interior LED lights (fitted by previous owner) had been left on overnight. I replaced the battery for a brand new one but no luck. I then took it to a specialist VW commercial garage who replaced the battery and said the issue seemed to be fixed. I was dubious because I had already tried this myself - so I had a feeling the problem would rear it's ugly head again.

Low and behold a week later the van wouldn't start again. This was after it had been left sitting for 2 days. I was able to get it jump started but it took a serious amount of cranking the engine (20 odd seconds) until it eventually laboured to a stuttering start. Once the engine gets running the van runs fine and can be turned on and off with no issues. I took it back to the same garage. No diagnostic codes were showing and there was no indication that there was a parasitic drain coming from anywhere. The new battery that they had already fitted previously was holding its charge as it should. They suggested it could be something to do with the fuel system but I was reluctant to have them spend hours looking for something they weren't sure about and took the van away. Since then I have driven it several times infrequently, usually starting the engine by turning the key to first position, wait for glow plug light to go out, hold down the accelerator while cranking and it's been working. Today unfortunately (another icy cold day) we are back to a non start.

Having done some digging on this forum and across the web, I do believe this is a fuel related issue. I think fuel is maybe draining from the system overtime and is unable to ignite when I go to start. I also think the recent cold weather has had something to do with it, many of the occasions when this has happened has been over a period of low winter temps (1 degree to -4 degrees celcius) whereas when I first got the van it would start first time with no issues. It seems to be intermittent so it's difficult to judge if temperature is indeed a factor. If anyone has any better suggestions I am all ears.

If anyone can point me in the direction of what things I should look for first it would be much appreciated. Me and my stepdad are going to have a look at this tomorrow, hoping to somehow get the van started before we start inspecting fuel lines for air leaks as a starting point. We are going to check the fuel filter as well but the van was recently given a full service at Halfords so I would have expected the fuel filter to be changed as part of that. Other things I read about are installing check valves for the fuel lines although we aren't confident on how to properly install these...same with the 'common rail' i believe it's called. I hear these are cheap things to change but there doesn't seem to be VW Caddy specific tutorials on YT or the web.

Thank you for taking the time to read this. I hope everyone has had a good Christmas and has a HNY when it comes.

[BenT]

Sorry to hear you're having problems, it does seem odd that it started happening suddenly - was it particularly cold the first time it happened? It almost sounds as though it's refusing to start when the battery voltage is below a certain value. I'd do a fault code scan first though , to narrow it down. It's well worth investing in a good fault code reader, or better still something like VCDS. Could damp be getting into the wiring somewhere?

Yours isn't a common rail so doesn't have fuel lines as such. There's a low pressure electric pump in the tank, a 3.5 bar tandem pump on the left hand of the cylinder head and the remaining 2000 bar pressure or so is done by the pump injectors themselves, internally. Good luck!

[Hw82]

Hi, can I ask if you ever got the problem sorted? I'm having the same issue with my 05 caddy. A mechanic said that its like the fuel was flowing back into the rank when not used, and for me to pack it facing downhill rather than the way I was parking, slightly uphill. Havnt used it for 2 days, it did not start this morning again

[STP]

This was a common issue on the Audi 1.9 TDI and was down to air getting into the fuel lines, at the pump or elsewhere. I fitted a priming bulb to mine and this sorted it for a while but had to replace the o rings on the fuel unions at the injection pump in the engine bay if I remember correctly.

The PD engine can also suffer from this due to the injectors bleeding air in, from bad o rings (not sure why this happens but DTE TV on YouTube covers it well)

[Hw82]

Thanks, il give it a try