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Starting troubles...

Posted: Sat Apr 26, 2014 4:35 am
by azazel
My diesel hdi 406 starts for a second and stalls. Often starts OK on the second try but sometimes its more difficult to get it going. Tank pump failed the other day but replacing that has not solved the starting problem as I had hoped. Any ideas?

Re: Starting troubles...

Posted: Sat Apr 26, 2014 8:43 am
by Doggy
Fuel filter's definitely worth ruling out, specially if you did have dodgy lift pump.

Also verify the filter body is being pressurised when you turn the ignition on, you can see/feel it swell a little.

Re: Starting troubles...

Posted: Sat Apr 26, 2014 8:54 am
by GingerMagic
I does seem fuel related, have all the fuel lines been flushed through or anything to see if there is leftover crap from the lift pump failure..??

Maybe air in the fuel line system, or maybe the air filter and pipework has a blockage?

Its gonna be a bit of trial and error, lets tackle things one at a time.

Re: Starting troubles...

Posted: Fri May 02, 2014 7:49 pm
by binnzy
I had a similar problem it was the cam sensor I took it out cleaned it and made sure the gap was set correct, the gap is the important bit if it's wrong you have starting problems

Re: Starting troubles...

Posted: Sat May 03, 2014 7:40 am
by PeterN
If its a 2.0.l I have had problems with the filter on the HP pump pressure regulator, they clog up but are very fine and almost impossible to clean.

Peter

Re: Starting troubles...

Posted: Sat May 03, 2014 7:56 am
by dirtydirtydiesel
PeterN wrote:If its a 2.0.l I have had problems with the filter on the HP pump pressure regulator, they clog up but are very fine and almost impossible to clean.

Peter
Out of interest, can it be changed easly & is it cheep :supafrisk:

Re: Starting troubles...

Posted: Sat May 03, 2014 9:10 pm
by PeterN
I got a secondhand one off ebay for not to much money but that wasn't very good either. One I had in stock didn't have the filter fitted so in the belief that it obviously wasn't essential I removed it - works fine now. An easier option is to grind the end off, making sure to remove all the swarf. The whole unit it secured to the pump by two torx screws

Peter

Re: Starting troubles...

Posted: Mon May 05, 2014 8:54 am
by azazel
My Mate who is a mechanic recons its the crank sensor. If not then I will look at the HP pump presure regulator. I still have the starting problems. Starts for half a second and then starts OK next time usually. I think the problem was compounded by the tank pump failure but I suspect they are unrelated. I will let you know when I fix it.

Re: Starting troubles...

Posted: Mon May 05, 2014 11:59 am
by PeterN
There are all sorts of things it could be, you really need the codes read with a Lexia, but that's what I found it was in my case. I also had one that was difficult to start when hot - that was the pressure regulator too.

Peter

Re: Starting troubles...

Posted: Thu Jun 05, 2014 9:10 pm
by azazel
Ok, sorted out.

Symtom- starts for half a second then struggles to start

problem- fuel pipe split and worn by the sound deadening engine cover. Tiny leak cuasing loss of presure of fuel system.

Fix- replace damaged pipe with rubber one sold by the meter.

Also had a code for cam and crank sensor syncronicity fault... Could be a dodgy cam belt maybe? I will investigate.

Re: Starting troubles...

Posted: Thu Jun 05, 2014 10:03 pm
by PeterN
Well done. I will try and remember that for future reference.

Re: Starting troubles...

Posted: Mon Jun 09, 2014 12:50 am
by bangernom1cs
Im now having this trouble too. But only when the car is hot or running for a while..
From cold it starts up a treat!
So far. . . (406 2l hdi exec)
Garage has connected the diagnostics and cleared out all codes.
Pump is still working well...hums sweetly for its three seconds.
New fuel filter fitted and all pipes seem sound. Cleaned out airflow meter .Oil and filter changed.
No warning lights on the dash. Have been running on V-power fuel for a bit.
Cam and crank sensor replaced with cambelt 2 months ago.
'compatibility' came up on the diagnostic and this was cleared. However car has run soundly for thousands of miles correctly since the change of sensors.
Ive used a bit of 'easy start' to get it going. As soon as it starts it goes for ever.
There are no issues when the car is running with enough power etc and good mpg figures. (47mpg in the last week 1000 miles of city and motorway driving)
I can switch it off after 3-4 hours running and it will immediately fail to start again.Once cooled its great!
Coincidentally. . . the cruise control has been erratic if not unoperational since this trouble started within the last 4 days.

Would the HP fuel pressure regulator thingy affect the cruise control function perhaps?

T

Re: Starting troubles...

Posted: Mon Jun 09, 2014 9:30 am
by steve_earwig
bangernom1cs wrote:compatibility
What with? :? Did you mean synchronisation there?

Nothing to suggest really, I only know about the crank sensor. Unless the new one's gone faulty...

Re: Starting troubles...

Posted: Mon Jun 09, 2014 9:43 am
by markw
Someone on the Coupe forum recently had identical problems with his HDi. It transpired that a recently replaced cam position sensor had failed again. It was replaced and all's been well as far as I know.
Assuming the 2ltr HDi has the same cam sensor set up as the 2.2...... :?:

Re: Starting troubles...

Posted: Mon Jun 09, 2014 9:53 am
by PeterN
The original problem I had was failing to start when hot, I thought it was probably the HP pump so I changed it and it cured the problem. When I later used the regulator off this pump for another fault, low and behold it wouldn't start when hot - so I changed the pump for nothing, mind you it did encourage me to change the cam belt and water pump.

I think its down to the filter in the regulator that causes the problem.

Peter