1.8t starting issue
 

My 2004 1.8t tourer auto has not been used for around 4 years but had been started periodically. It also has a dual fuel LPG conversion. I need to move the car soon so thought I'd check it out today. Initially the car wouldn't start. I checked for a spark and all was good but it just wouldn't fire. The LPG setup is pretty standard, starts on petrol until a predetermined temperature is reached when it flicks over to gas. This can be overridden though so that the car will start on gas. Having done the override procedure, it fired up an ran very well on gas except that it would only idle and would instantly cut out of I attempted to rev it. Once the car was up to temp I tried to flick back to petrol and it just cut out. I can't hear a fuel pump kick in from the petrol filler neck so could it be a failed fuel pump?

Failed pumps are rare, but everything fails eventually. However, I reckon there are more likely causes. You mentiaon there's no pump noise, so check that first by getting an assistant to turn on the ignition while you listen at the tank filler hole. The pump should run for 5-10 seconds then stop (it requires the engine to start to keepthe pump running). If no pump sound, check the pump relay that's located on the interior fuse board.


https://www.mediafire.com/convkey/20...k3nsgery6g.jpg


It would also be worth checking (unless you know already) whether the filter module in the fuel tank has the Orange Clip fitted. If not, a separated module will prevent any possibility of starting.


TC

Thanks, that's a comprehensive response and it will give me a few things to check tomorrow. Yes checking the filter module for the clip was on my mind too so I'll check it out after the relay.

I've check for the clip this morning and it is there and all is sound with the filter. The pump is definitely not kicking in and the relay is fine. I swapped it for another just to be sure. I peered into the tank on the filter side and it's pretty much empty to be honest. I know it's a saddle tank but is it likely to be just as empty in the other side? Maybe this is why the pump isn't working as it knows there's nothing to pump? Maybe it's evaporated after 4 years standing, maybe the fuel has deteriorated? The fuel light is on but by no means at the bottom of the gauge. As I said, it's been stood a while. I'm gonna feel like a right numpty if it's just low on fuel!

The levels in each side of the tank are normally balanced by the in-tank venturi pumps. See this for details: https://www.the75andztclub.co.uk/for...d.php?t=108535

I can't see how long term evaporation would reduce one side more than the other.
Anyway, add a gallon of fresh juice to eliminate that from the equation. The pump should run whatever the fuel level. I don't think it's clever enough to react to levels. You might check the continuity of power through the motor. Remove the right side tank hatch cover and you'll see the pump/floats system connector. Pull the plug off and use an ohm meter on the appropriate pins (2 & 5) to check that the resistance is OK. If it's open circuit or a vastly different reading from that shown below, then the pump should be replaced.
https://www.mediafire.com/convkey/20...727zkia36g.jpg


You might also confirm that power actually reaches Pin 4 when the relay activates.


TC

Brilliant. Thanks so much. That's a job for tomorrow.

Hi guys,

Does this diagram and readings also apply to the single pump MK2 CDT? I think ours has a fuel gauge problem.

Thanks,
Glenn

Probably. There's only ever been this single diagram published, so we must assume it applies to both fuel systems. The single pump diesel will have a field resistance in the same ballpark as earlier ITPs. It woukd be worth (someone?) doing a measurement though. However, the usual problem is not with the field coils resistance as such, but an open circuit due to brush/commutator wear.


TC