406oc.co.uk

Hi All,

We have a 2.0hdi, 181,200 miles, 2000. Drives faultlessly apart from occasionally cutting out . Has happened three times so far.

1) First time was 15 June, 180,200 miles at 30mph, travelling down a slight slope on a straight road, about 10 minutes after starting off. The car just cut out, and would not re-start. The engine management light came on. It was recovered to our house, and on the following day did start, although the engine management light remained on. The garage were unable to find any useful information using their fault code reader.

2) Second time was on the 26 June, again at 30mph, just after a roundabout, about an hour and 50 miles after starting off. The car just cut out, and would not immediately re-start. The engine management light came on. After about 20 minutes the car did start, although the engine management light remained on. It drove 3 miles to the immediate destination, then stayed there for 4 or five hours. It made a further very short trip, then the 50 mile trip home, still with the engine management light on. The garage were unable to find any useful information using their fault code reader, however the did find very low pressures in the high pressure pump, and next to no fuel returning to the tank in the leak off pipes. They therefore changed (ouch!) the high pressure pump and (since it was due anyway, and needed to be removed to change the pump) the timing belt.

3) Third time was on 08 August, again at 30 mph, on straight level road. Car had driven 50 miles in morning successfully, then been parked for 4 hours. It cut out about five miles into the return trip. The engine management light came on. It would not immediately re-start but after only about three minutes it did start, although the engine management light remained on. It drove the 45 miles home, still with the engine management light on. The garage were unable to find any useful information using their fault code reader but took it for some trips (total 25 miles) with their laptop monitoring it - everything checked out as fine with no problems.

Since then we have driven 150 miles without problem, however we no longer have confidence that the car will keep running. The garage suggest perhaps a sensor fault, or maybe a wiring fault, but they admit to being pretty much in the dark. Neither they nor I am keen to diagnose by random part replacement.

Any suggestions anyone, for how we can diagnose the problem?

Regards

Simon

Apart from the HP pump, probably the most expensive part of the fuel system... How's the lift pump?

Hi Steve,

Thanks for your quick reply.

Well the garage tell me that (even!) they are reluctant to change this at £500 or so - the pressure in the LP side of the fuel system is OK apparently.

Regards

Simon

If you've never had the Low Pressure pump changed then I would look at this first, the symptoms are random cut outs. In fact the next time it happens, jump out and give the fuel tank a big slap and see if the pump springs into life - if it does then it's faulty and not delivering fuel properly.

My car cut out like this once but has never done it since but my mechanic immediately stated it would be the crank sensor!

Hi Welton and thanks for replying. I have seen references to crankshaft / camshaft sensors giving these sorts of problems. My current cunning plan is this: I have ordered a laptop interface (£35 off eBay - I decided against the 99p, model from Hong Kong) so that we can monitor what is going on in real time, and also hopefully get some useful information if and when it stops again. The seller assures me that the device will work with the car - hopefully it will arrive tomorrow.

Interesting threads turning up on low pressure pump:
* These engines and poor biodiesel: http://www.vegetableoildiesel.co.uk/for ... p?tid=2317
* Simple failure: http://www.bba-reman.com/auto-mine/peug ... roblem.htm
* Adds possibility of filter casing breaking up : http://forums.preloved.co.uk/fuseaction ... d0cf6.html
* This chap changed both pumps without solving the problem: http://www.fixya.com/support/t236753-peugeot406hdi
* Loads of ideas here: http://www.bba-reman.com/auto-mine/prob ... px?make=20 including:
__ * ECU fault
__ * fuel pressure sensor
__ * double relay positioned next to the ecu
__ * 14th tooth after TDC (!)
__ * Some cars do not have an electric lift pump, just a priming bulb somewhere - but they do all have the wiring to the tank,
and it goes live when the pump should run, even if there is no pump.
__ * Check for metal filings in fuel filter housing as sign of pump failure.

I will post again when there is any news. Regards, Springnuts.

OK the pump is a VDO - £150 on eBay and ... er ... £132 from main dealers. One of the companies recommended checking the wiring from the fuel pressure sensor on the accumulator rail, so I gave it a good 'wiggle' - no problems, engine did not stop. Interestingly the connector where the wire from the sensor joins the main loom is just hanging loose - it has broken away from wherever it is supposed to live, perhaps whilst the high pressure pump was being changed. But this is not the problem. We have a trip of a few hundred miles this week, so will see if there are any problems.

Thanks for all that, very interesting. I was wondering about the pressure sensor but, as it's almost 200 quid ( ) I didn't really want to mention it, as you say it's better to diagnose the problem than keep bunging cash at it.

Safe journey anway. Let me know if you want a pic to see where that wire goes.

Hi Steve, Thanks and yes a phot would be v useful - it is pretty much just dangling about at the moment! Simon.

Bumholes I followed the wire down from the sensor as it disappears down in front of the block and there I found a connector just dangling about, just like yours, and then it goes in the plastic trunking with the rest of the wiring. I reckon it came from the round plastic thing in the hole in the crankcase to the right. Another job for a cable tie I reckon, and I only had it in the air yesterday

Hi Steve,

Yes that's the place - makes sense now. The black plastic connector has a tiny spigot to fit in the hole in the block, then the black disc you can see a bit of in the photo, then a small plastic strip - like the deck of a tiny aircraft carrier. This then slides into the yellow cable connectors where it clips into position.

I have looked the clips up and they are £25.96 + VAT each from the main dealer.

Regards

Simon

PS - Actually I made that up about the £25.96 + VAT.

That's ok, I still have millions of cable ties I "liberated" from work before I left

(If you can actually identify it, it's probably about 50p)

My connector is doing the exact same thing, apart from mine's covered in Diesel/Oil

My car has done this 3 or 4 times an it is scary....foot down and you go slower

The culprit on mine is the throttle position sensor! I'm surprised the Peugeot garage haven't picked up on anything. No wait, I'm not surprised

If they've reset the engine light each time they should also have called up the reason for the fault aswell

At the risk of boring you half to death you could have a nose around on this site, there's some auto diagnosis bods on there with some usefull info.....http://www.ilexa.co.uk/forum/index.php/board,22.0.html

Welcome by the way

OK as was predictable it died again - I was away so the garage looked at it and said they don't know why. I described the symptoms to an engineer chum, and his immediate comment was - "Pump relay - old and tired; terminals get a little burned and corroded - just occasionally lets go". That before knowing any of the suggested issues. So I am looking on £11+VAT as a diagnostic expense, and will let you know.

It's always possible. I had something similar on a Pussat, it was two relays though (one for the pump and one for the entire engine management) and they led me a merry dance. It wasn't corroded terminals though, it was dry joints on the tiny circuit boards inside the little darlings.