TD4 Issues ... on going

Hi all,

After a spate of car not starting (2001 td4 auto) and cutting out, its been to the garage.

Symptoms :

In the past 3 weeks

1) Sometime when warm, it won't start, turns over fine but won't fire. Even after it cooled down for a couple of hour. leave it long it start first time

2) It cut out completely once while driving

Longer running issues

1) Labouring going up hills, until it kicks down
2) Lump running 1000 to 2000 rpm
3) Lack of power before turbo spools up

Garage (DCV, Doncaster) have had the car almost a week. There are no fault code on the ECU, the car has started everytime.

They changed the Fuel Rail prussure sensor, and wiring harness. This made no differnce.

They then cleaned out the crankcase filter and the rough running went away.

They put back the old fuel rail sensor back on, and still the lumpy running is not there, aparently.

Call me cynical, but i have already changed the crankcase filter once before and the issues still continue. Really? That fixed everything?

I have found that all the garages around where i live are next to useless and know nothing (jack of all make, master of none) unless you want the brake pads / exhaust / battery changed. Even the stealers have looked and failed in the past, blaming the air filter, which was changed and made no difference.

It looks like I'm going have to buy some spanners, and figure it out myself. Where should I start looking?

low power or power dropping off below 2k is 99% of the time a maf issue... disconnect it and see if theres any difference. these rarely show up on a diags check as even when they are running out of spec they are sending a signal to the ecu so it thinks its fine. get the egr valve off and give it a clean and check both the intercooler hoses for any tiny splits...

when warm and turns over but wont start --- have a look at the cam shaft sensor it plays tricks like that but should start when cold

OK I now have the car back.....been an got it this morning

They have checked the MAF, done leak back tests on the injectors (one leak off a little more than the others, but no enough to worry about). Checked the fuel supply with a pressure gauge. They found nothing wrong.

Nothing showing up on the ECU, autologic info all looked good.

They change the fuel rail sensor and harness, no change.

They cleaned the PCV foam filter out, and cleaned out the EGR value. This cured the rough running and the pause below the spooling up.

They have not seen the bad starting issue, but they say that it could be the HP fuel pump that isn't building pressure when warm, especially considering it has done 212K miles.

Will see how it goes up hills later............

hi you did not say it had done that milage before did you have you changed the fuel filters at the milage on it you should have done

Hell yeah. I might get rid once its round to 300k )

I'm please to say that it made up the hill that it usually struggles with (think that's because I took the turbo exit filter off last week)

There no guarentee that it won't fail to start again again.

So back to the bearing noise then.......