Fuel pump(?) problem on a 96P 2.5di

[Paulus]

Seasons greetings to you all, from a newbie.

I'm hoping someone can shed some light on this problem?

My 2.5di cut out on me, on the motorway, without any prior warning. There was no bang, no faltering, coughs or splutters. It simply stopped running, coasted to a halt and then refused to re-start (I'd tried bump starting it, as it coasted).

Having run it very low on fuel prior to it's last fill and not having changed the fuel filter recently, I wondered if water/c**p had blocked the filter. (There was water, in the fuel which ran out, when I took the water trap off the filter). So I dropped the tank (the fuel left in the tank was a little cloudy and dirty), cleaned and dried the tank out, blew the lines through (as best I could), replaced the filter (pre-filling the new filter with clean fuel), before half filling the tank with clean fuel. The fuel lines were reconnected in the right order and the fuel pick-up unit looked to be clean and intact. I also checked that the timing belt was intact and turning, when the engine was turned over and that the fuel cut off switch had power to it, when the ignition was on (I couldn't hear any click from the switch though, when the ignition was turned on and off).

Having tried to start it repeatedly and failed (using a booster to help the battery turn it over fast enough) I loosened off 2 of the injector pipes at the injector end. No fuel came through, after repeatedly turning the engine over, so I tried the bleed on the side of the pump (It's a Bosch, by the way). Some fuel did come through the bleed nut, after 10/15 seconds of turning it over, although not as much as I would have expected and certainly not a constant flow. In desperation I attached a pipe to the bleed and sucked fuel up the pipe, tightening the bleed nut before it ran back. Still it wouldn't start!

Prior to this happening I had no starting problems, even in very cold weather. She always started on the first flick of the switch. The fuel pump looks to be OK externally, with no visible leaks or damage, as do the filter housing and the plastic fuel lines.

I'd be grateful for any advice or suggestions, before throwing myself to the mercy of someone like LUK. At this time of year funds are tighter than ever and the cost of a new or even reconditioned fuel pump scares me!

[gemini]

it may be the fuel solenoid on the pump, check there is power to it, if so it could be faulty

[Luke]

yep as gemini says the shut off solenoid would be what i would look at first! should be a 12v feed!! mabe the wire has come off???

[Luke]

also welcome mate you are member no. 666

[Paulus]

Thanks for the welcome and words of advice, although I'm not too sure about my membership number! That said, I am having a HELL of a job getting this trannie to start

I've definitely got power to the solenoid, when the ignition is on, as I've already tested that. However, I'm not sure how to test the solenoid itself or how you remove it from the pump?

[100ps_drw_hicube]

before all this happened was the van slugish on start up from cold as one of our old mk5 's done this turned out to be a little spring inside the pump had snapped cost about £180 to get the pump rebuilt

[Gunslinger]

by the sounds of it it was running fine then simply shut down and refuses to start right ? ... no coughing or spluttering a couple of miles before or anything like that would have warned you something was wrong ..... if this is the case then my attention would be on that little soleniod valve too.

[Paulus]

Thanks for the info guys. I'll try swapping the solenoid and let you know the outcome. Here's hoping!

[Nighthawk]

I'm in a little late on this one.

If the vehicle has PATS which it should on a 96 i'd have a quick of fuses first. Because short of removing the cover from the solenoid, there isn't much of a confirmed way to check V+ at the terminal. Depending on build, some of the fuses for PATS system don't have accurate descriptions and will cause the vehicle to crank but not fire.

Pay attention to the brake light fuse and the 3 5amp fuses up in the top right.

Also, is the REd led doing anything while your cranking?

Rapid flashing (4Hz) would suggest a fault on the PATS.


If it is the solenoid, remove the fuel pump return pipe and it's union from the pump, remove the protective cover from the solenoid if fitted still.

undo the wiring terminal and undo the solenoid, be careful here because the plunger WILL fall free of the solenoid. There is a very small spring inside the plunger....again don't lose it.

Check for metal swarf or bits of plastic both on the pluger and inside the solenoid.....they will usually be found in the threaded union you removed to get at the solenoid.
Anything there means the pump is on the way out, so start saving

If you don't find particles to cause concern, you have 2 options

1 leave the plunger and spring out (safely) and rebuild it, run the vehicle...if it runs the solenoid is U/S you'll have to stall it now though because the interesting bits of the solenoid are in your pocket

2 put the plunger and spring back inside the solenoid and connect the other end to a fused 12v supply, earth the solenoid out on the engine (eg), as it earths, it should "click" the plunger bak inside against the spring pressure.

[FredTransit]

Welcome, Paulus. I am bit late on theis one too, so what I would have said has been said, at least about the soleniod. How's it going with this one?

[Paulus]

Many thanks for the advice and tips. Unfortunately though, she still refuses to start.

I checked the fuses, which were all OK. The PATS light comes on and goes out, as normal, and doesn't flash when cranking the engine over.

I removed the solenoid, as per Nighthawk's detailed instructions (Thanks ), which was clean and free of any swarf as was the fuel left in the pump housing. I tested it's operation by bridging a wire from the battery's positive terminal to the lug on the solenoid, then holding the solenoid against the negative terminal. Whenever contact was made the plunger was drawn back inside the solenoid, so it appears to be working properly. I also re-checked, with a test light, that there is power down the solenoid wire whenever the ignition is turned on, which there is.

I removed the plunger and spring, from the solenoid, before refitting the solenoid to the pump and tried starting the engine(Just in case the plunger wasn't opening enough to let sufficient fuel through), again without success.

I opened the bleed nut, on the side of the pump, connected a length of clear pipe to it and fed it into a plastic bottle. After repeated bursts of 20 seconds turning the engine over, hardly any fuel came through. So I sucked on the pipe, until it was full of fuel, then tightened the bleed nut before trying to start the engine again. Still no joy.

Could a vacuum failure be the cause of this? If not, I'm open to any other suggestions or advice anyone can come up with.

[gemini]

try filling a gallon can with diesel and put the fuel pipe straight into it just in case there is an obstruction in the tank or fuel line/filter etc,

[jay]

does it have a seperate fuel pump on the side of the block??or do these suck fuel up from the injection pump??just thinking it may be the pump no good.

[stevew]

Good point.
I've seen some without the fuel lift pump and some that have haad it retro fitted to solve 'fuel pump air lock' problems, though they didn't!
My '97R has a lift pump but it's the turbo engine.
If it does have a fule lift pump those things can stop working very quickly if you get a hole in the diaphram. If that happens you may see diesel leaking out of it as they have a small bleed hole (to equalise the internal pressure?) in the side. Mine leaks oil out of it! I must get a new one before the whole van is black underneath.
Steve

[Paulus]

try filling a gallon can with diesel and put the fuel pipe straight into it just in case there is an obstruction in the tank or fuel line/filter etc,

Thanks for that one, Gemini.

I disconnected the injection pump inlet pipe, from the filter housing, attached some more pipe to it, stuck it in a gallon of fuel and tried to start the engine without success. No fuel was being drawn up the pipe, so I opened the bleed nut, attached another pipe to that and sucked. When I did that fuel was drawn up the pipe from the can, as well as the bleed pipe. By my reckoning the pump was now full of fuel, so I tried to start it again. The only fuel, apparently coming out of the pump, came from the open port on the filter housing! (From the return pipe, I guess?)