2.0HDi Hot starting issue

snowball · Post by **snowball** » 19 Aug 2010, 14:38

Hi,

I've got a 2.0HDI which has started having intermittent problems starting when hot. Always OK when cold and once started runs normally. Issue seems to arise after a longish run when everything is hot.

I'm assuming that the fuel pumps and rail pressure sensor are all OK because it does start fine from cold. So I'm wondering about an electrical issue? Some relay or switch? Wiring? Battery getting old?

Is there a 'common' problem? The car is a 53 plate Partner/Berlingo 2.0HDI with 103K miles, timing belts/crank pulley/tensioners done at 96K.

I'm currently 250 miles from home and hoping to catch the ferry to Dieppe on Saturday morning.

If anyone can recommend a fix or a decent indy in the uckfield, east sussex area then I'd be grateful.

thanks.

Mark

Pompey_Dave · Post by **Pompey_Dave** » 19 Aug 2010, 15:38

just an idea, but my mate had this problem on another car, some times it was fine, other times it wasnt....May be irrelevant, but possible crank sensor?

Whenever his car was warm it wouldnt start, but again it was only now and again

snowball · Post by **snowball** » 19 Aug 2010, 16:02

Cheers Dave,

thats a good point. I'd sort of thought that a crank or cam sensor might cause problems while running - cutting out or misfire. I've never had one go though.

Post by **RichardW** » 19 Aug 2010, 16:30

You really need to get it on a Lexia to see what is going with the fuel rail pressure. It could be a cracked injector that is only opening up when warm, causing the rail pressure to leak off and making starting it difficult. Once up and running, the HP pump compensates for the leak off.

MikeT · Post by **MikeT** » 19 Aug 2010, 16:49

Quite often I've seen these warm/hot starting problems reported on HDI's and it does seem to be the crank sensor is the most likely culprit - whether it's a design fault, I don't know - but a quick check, clean and refit can sort it as some simply move back far enough to not get a coherent pulse.

snowball · Post by **snowball** » 19 Aug 2010, 17:10

Thanks Guys.

I've been scouring the interweb today - I found a comment in a thread on the ilexa forum that one of the sensors (cam/crank? Cant remember - I'll have to go find it again) is only used on startup.

Richard, can I check the pressure using a multimeter on the sensor? Does it just vary resistance?

The Seasider · Post by **The Seasider** » 20 Aug 2010, 02:03

its your "COOLANT TEMP SENSOR" that gone "DUFF" .....

2 ways to Attack this

1. replace the coolant Temp Sensor .....

or

2. fit the "Hot Start Fix" resistor from a BMW/GM diesel engine

The poor hot starting is caused by internal wear in the injector pump,when it gets warm the internal clearances open up and the pump produces a smaller start quantity.Also above 60c coolant temp the glows dont operate and there is less pump advance.

The hot start fix available on E-Bay puts a 2.5k resistor in place of the real reading of the coolant temp sensor for about 20 secs every time you key on.This puts the glows on every time and advances the pump timing.Bit of a bodge really,but it works well and is more palatable than a pump rebuild.