Erratic Running :(

My L Series 2.0D is running erratically - I first noticed when on a long straight road the other day when fuel consumption was high but since then I have been able to create a condition when it is most noticeable.

In 4th or 5th gear at low speed (30mph) and half throttle it is just as if I am turning the ignition off and on again.

If I put my foot right down though I get good smooth acceleration.

Does anybody have any ideas?

Been out again testing - it seems this only happens when the engine is hot.

I found a hole in a leak off pipe and replaced that pipe but no change, COULD it be air getting into the system?

It sound like a fuel pressure fault or dodgy injector

I changed ALL of the 3.2mm pipes today - no change.

When I got it hot enough earlier and it started its 'Erratic Running' I disconnected Injector 1 from it's electrical connection (What Is that?) just to see what happened and absolutely no difference.

How do I find out which injector it is? hoping it IS NOT the Pump

If you unplug the wire and no difference that tells you that it's that cylinder you have the problem with as the wire is what tells the injector to inject the diesel into the cylinder so it's either the wiring or that injected that's faulty I'd say the injector as I've had the same problem with my td4 take the injector out and get it tested best bet

Zippy6971 said:

If you unplug the wire and no difference that tells you that it's that cylinder you have the problem with as the wire is what tells the injector to inject the diesel into the cylinder

Click to expand...

I'm sure the OP knows that's not right for the L Series. There's only 1 injector with a wire and its a timing sensor feed to the management system that it uses for timing to all injectors - it doesn't control the injector - its used to control the pump.

TBH I don't have sufficient knowledge to make any suggestions that you could take any reliable input from - but I somehow doubt its the pump - they're pretty reliable.

Many thanks for all of the replies.
I dont think it's the pump as I have no problems on acceleration.

I went to buy a Trailer from a Land Rover fan yesterday and he said it could be the EGR Valve ? is that possible??

I suppose it could be. The engine is designed to suck in enough air (oxygen) at full power (fuel delivery). The ECU will open the EGR when the engine's not drawing full power to replace some of the air with exhaust gas. If its opening to far at that throttle condition, then it could be starving the fuel of enough oxygen to ignite properly/fully. If there was a problem with the EGR controller (on the bulk head) or the vacume hose to the EGR - I'm not sure if it would fail open or closed.

Also if its not burning all the fuel going into the engine, might that also be accompanied by smoke?

If the EGR itself was clogged up with soot, I'd have though the problems would be towards the higher rev range when gas seeping in really would screw with the demand for oxygen - as you've had it up to 90mph recently, that rather discounts that!

Worth checking out - I'm not sure if you can simply disconnect the vacume hose so that you know its not opening at all. As I say, I'm not sure - that may cause it to stay open or even put the ECU into some form of limping mode if it detects an EGR not working properly. I'm not sure where the vacume comes from either - whether its the controller or the same feed to the brakes!

I can't get the EGR off, I have the silver bottle type device off (with a water jacket onside) and am soaking that overnight in Diesel.

The EGR doesn't feel sooty inside, I have given it a good dose of Penetrating oil and will continue to top that up over this evening.

I did connect a vacuum hose to it and with the engine running tried to get it to open (creating a vacuum with my mouth) but it wouldn't open.. BUT after what you said about it only operating at a certain engine state I suppose it wouldnt open yet.

Good point, I dont know where the vacuum comes from either - I can see it is connected to the Brake servo ! I dont think this valve is at fault

I am replacing all of the hoses one by one as I go.