Help! Strange Hard Start Problem

[Hosta]

Hi guys,
I’m new to the forum but I thought this might be a good place to ask some questions regarding my Transporters strange hard start problem. I’ve had 3 separate mechanics look at this for me and it’s left them scratching their heads.

Okay so it’s a 2007 T5 Transporter T30 2.5 TDI. After a journey, and left to sit a few hours or over night it’s becomes really hard to start. I turn the key it and just keeps cranking, I have to do this 2 or 3 times then it’ll start (scared to burn the starter out). But, when it does the hard start and then it starts, and I don’t drive it anywhere it doesn’t do the hard start again even if I leave it overnight or a few days. So it’s only after a journey will it do this.
I’ve had EGR replaced, glow plugs and glow plug relay replaced and a problematic injector (according to the diagnostic tool) replaced. It runs completely fine, no engine light on or any other lights, no misfires, no rough idling. Fuel pump seems okay cause when I turn the key I can hear it hum and hear the engine prime. New battery and a boost leak fixed too. Also new starter installed.
Can’t figure it out. Not sure if it’s a leaky injector problem as it’s not hard to start every time. I thought it might have been a temperature problem, but after it hard started and I didn’t drive it anywhere I just let it idle until it reached operating temperature and let it sit at the for about 15-20 mins, I shut it off, and next morning it started no problem.

I’m at my wits end about this. I know that’s a huge post and a lot of information, but if anyone has experienced this or could point me in the right direction I would greatly appreciate it. Thank you.

 

[Merryman]

So, hard to start again after a long journey, but seems to start after a warm up, and leaving overnight.

My first thought is dirt in the fuel tank, being sucked up into the system, and the more on a long journey or running time. This would then take a lot longer for the muck to drain back into the tank. Where as in a short engine run, less dirt.
If I am right, disconnect the fuel line from the tank, and to as near the engine as possible and blow through, clean or replace. Or start at the cheapest option, and and drain the tank, remove, and wash it out.
If there is a load of muck. Then thoroughly check the fuel line to the pump. The fuel line in the tank is often referred to as the 'Stack Pipe' and was a common issue on very old metal fuel tanks ( Bedford coaches and lorries for example). For rust to block the line, letting enough fuel through to start the engine, but would then reduce revs as more fuel was required. This was on old injector pumps of course 1950/1960 era.
Hope the suggestion gives food for thought and am sure, that someone on the forum has resolved a similar problem and can help you out. Good Luck

You're profile just say UK, there maybe a guy in your town. Two heads etc,

 

[Hosta]

Thanks for your reply Merryman.
This is something I will have to look into. I did think it could be dirt in the fuel. I got the van serviced about two weeks ago and had the mechanic open the old fuel filter to see if maybe it was clogged and that’s what was causing the hard start. But after opening and examining it, it was to my surprise, as clean as a whistle. So that kind of put the thought of dirt in the fuel system out of my head. Unless what you’re telling me has nothing to do with the fuel filter and just be dirty fuel running straight from the tank to the engine? Sorry for my ignorance, I’m not the most mechanically minded.

 

[Merryman]

The fuel filters are dam expensive about £65. If yours was really clean, then possibly no muck in the line, as you would certainly have had to change the filter. If it showed anything at all. Most mechanics wouldn't pass up a 30% commission fee for providing one.
Fuel MUST run through the filter, and has no way of a direct tank to fuel pump. I have known some Black Cab owners and Land Rover owners to install a second filter in line with the factory one. Rather than lose money with the vehicle off the road.
Was the mechanic VW, trained VW, modern diesel mechanic or someone you have always used? Have never known a mechanic to show you the receipt for the parts. You would be amazed at the mark up. A card of 24 signal bulbs less than £10, and charge about £5 including fitting. Fuses bought by the hundred. Windscreen wipers at £8 and sold for 0ver £20. If they didn't have huge mark ups they would just charge more elsewhere in order to cover their overheads and wages. So swings and roundabouts really.

I bought an electric window motor and thought I could do it myself, this was on a Chevy Astro van in Florida. Well the dam thing was pop riveted in, so had to use a mechanic I had used many times before. Gave him the part and he said he couldn't use it, as part of the deal was the profit he made on the supplied part. He explained it this way. Would you take your own burger into MacDonald's and ask them to cook it for you. Point made.

 

[Murdoch]

Dual mass flywheel / clutch issues?

had a similar experience on a Ford and it was the dual mass clutch that was causing it

 

[mmi]

2007 T5 Transporter T30 2.5 TDI.

What's the engine code - AXD, AXE?
What's the mileage of the van/engine?
When it eventually starts - does it run smooth and all cylinders right away?

After a journey, and left to sit a few hours or over night it’s becomes really hard to start.

when it does the hard start and then it starts, and I don’t drive it anywhere it doesn’t do the hard start again even if I leave it overnight or a few days.

Could it be air gets into (high pressure) fuel supply line between fuel pump and injectors?

I'm a bit curious if you would let engine cool down after a journey graciously by letting engine tick over at least 5 minutes AND have cabin heater at max heat with blower at max - would it then start normally?

 

[Hosta]

Dual mass flywheel / clutch issues?

had a similar experience on a Ford and it was the dual mass clutch that was causing it

Thanks for your reply Murdoch,
I’ll have to look into this to see if that describes the problem I’m having.

Forgot to mention she is an automatic, not sure if that makes an difference to dual mass flywheels. But just had the DSG gearbox serviced too with new oil and new filter and everything seems fine there, she’s engaging gears like it always has.

But will look into what you said, cheers!

 

[Hosta]

What's the engine code - AXD, AXE?
What's the mileage of the van/engine?
When it eventually starts - does it run smooth and all cylinders right away?


Could it be air gets into (high pressure) fuel supply line between fuel pump and injectors?

I'm a bit curious if you would let engine cool down after a journey graciously by letting engine tick over at least 5 minutes AND have cabin heater at max heat with blower at max - would it then start normally?

How do I find the engine code? ( I’m a noob when it comes to engines and the like )
It has 144000 miles on it.
And yes, everything seems to run smooth after she’s started. Nothing odd that has caught my attention anyways.

I can most certainly try what you said and let it cool down for 5 mins before shutting her off. Anything to help narrow it down at this stage. I’ll be away in her for the weekend so will try that then and get back to you with what happens.

Thanks for your reply mmi, I appreciate it!

 

[mmi]

How do I find the engine code?

It's on a sticker under dash by steering column, or on service booklet.
Is it 96kW/130PS (AXD), or 128kW/174PS (AXE)?

 

[Dellmassive]

i had something similar on a 2008 renault trafic.

it was a couple of leaky injectors in the end.

they fired the parts canon at the van as it was in warranty.

but ultimately it was two injectors.

apparently it wasnt enough atomised fuel to fire at the low revs on the starter motor . . .

but would settle down when up to speed on the revs.


+++++++++


so could be worth getting the HPFP and injectors tested at a Diesel specialist.?

they put the injectors on a bench machine that meters the spray pattern and quantity over time. - that will highlight any injector problem.

HPFP may have issues causing low rail pressure?

do you have access to VCDS for scan data?



+++++++++++


also had a similar issues with a neighbours Ford Mondeo TDCI - the only way to get it started was a can of easystart down the throttle body. and two jump backs of battery power to get it to fire.

that was a failed HPFP that put metal filings into the fuel and knickered the injectors.

the fix from the derv specialist was:

recon HPFP + 4x injectors + fuel system flush

when we went to collect the car. . . . he had sandwich bag half full of a fuel sample from the car.

which looked like normal diesel - with no sediment.

he then got a magnet out moved it around the bag, and like magic you could see the metal filings . . being dragged around the bag. (proof that the HPFP was toast)
it was very interesting to see.


+++

 

[Hosta]

It's on a sticker under dash by steering column, or on service booklet.
Is it 96kW/130PS (AXD), or 128kW/174PS (AXE)?

It’s 96kW/130ps

 

[Sioux101]

Had similar when we ran T5 2.5 on one. Cant remember it all but fuel was draining back from filter to tank, hence cranking to refill filter. Injector are driven by cam lobes, check PD oil used and no excessive wear, also position sensor. There is what I was told mechanical pressure bypass for un injected diesel.
Best engines made, reliable, no cam belt crap. Silly power dip if free wheeling and try to pull away in second.

 

[jordanL]

So, hard to start again after a long journey, but seems to start after a warm up, and leaving overnight.

My first thought is dirt in the fuel tank, being sucked up into the system, and the more on a long journey or running time. This would then take a lot longer for the muck to drain back into the tank. Where as in a short engine run, less dirt.
If I am right, disconnect the fuel line from the tank, and to as near the engine as possible and blow through, clean or replace. Or start at the cheapest option, and and drain the tank, remove, and wash it out.
If there is a load of muck. Then thoroughly check the fuel line to the pump. The fuel line in the tank is often referred to as the 'Stack Pipe' and was a common issue on very old metal fuel tanks ( Bedford coaches and lorries for example). For rust to block the line, letting enough fuel through to start the engine, but would then reduce revs as more fuel was required. This was on old injector pumps of course 1950/1960 era.
Hope the suggestion gives food for thought and am sure, that someone on the forum has resolved a similar problem and can help you out. Good Luck

You're profile just say UK, there maybe a guy in your town. Two heads etc,

Hi, did you get this sorted? I'm having similar issues. Can go weeks with no problem then can do it sometimes after long journeys or sometimes after a very chort journey. Has anyone mentioned a crank sensor?