2.5 td limp mode testing

[igotalake]

Hi all,

Got a motorhome on a 1995 2.5 td 100ps with epic pump, the second pump in as many years in fact. Problem is as usual, it went into limp and gradually got less and less time after switching off and onn again before going back into limp.

Anyway, using the LDV epic service manual i have tested everything they say without using the break-out-box, if that makes any difference, took my time to work through the diffeernce between BOB terminal numbers and actual pump or ECU terminal numbers but got there in the end and everything tests within the limits given in the manual. I only tested with a volts/ohms meter and with the engine off so not as good as a laser 2000 and I know that things could be different once the engine is running but what can i do next? I have the old pump handy as well. I did think about swapping over each sensor /actuator one by one to see if by chance it was a different fault from what it was last time but haven't got round to doing it partly because if i have the same fault on both pumps then i'm wasting my time.

Anyway, can you tell me what are the usual suspects when an epic goes into limp mode? They seem to be unreliable so what is it that usually goes wrong? So that i can narrow down my search a bit.


Thanks in advance,

John

[MinorMatt]

Where are you John?

[igotalake]

Thanks for the reply Matt, and i know you've got a laser 2000 but unfortunately i am in France! I have asked around here and none of the local garages have got it either.

Another thing i noticed while checking things out is that if i disconnect the vac line from the egr/throttle valve then the throttle valve moves but on reconnecting it doesn't move back. In fact the vacuum is gone and doesn't come back at least whilst just idling, unless i stop and restart. Does that tell you anything?

[igotalake]

No one got any ideas as to what goes wrong with these pumps ?

[MinorMatt]

Most common pump fault is ESOS - whic causes running on.

2nd most common is the cam ring sticking (new pump), or sensor failure (can be swapped in situ).

Also throws in to limp mode when the timing is out

[igotalake]

Thanks for the reply Matt

It doesn't run on at all but the cam ring could be the problem. Is it 'fixable' as this is the second pump in 2 years/20,000km? Is it worth trying to free it up?

As regards sensors do you mean the ones in the pump or external? is there a prime suspect? As i said, I've done all the resistance tests in the LDV epic manual and all was well.

Sorry for all the questions.

Here's yet another : One or twice after starting it has run ok for 30 seconds or so. I noticed that just before the light comes on it gets a bit noisier as if the timing was out. Does that point to the cam ring?

Thanks again,

John

[MinorMatt]

Cam ring is normally in fault or not... but it could be.

It may be cheap diesel causing cam rings to sieze. Diesel used to have sulphur in to lubricate, and it doesn't any more so a lot of people put 2 stroke oil in the diesel to make up for it

[igotalake]

I think i will try a bit of 2 stroke in the filter and in the tank and see what happens over the next tankful of diesel. Maybe it will free up.

If not, i will take it apart and have a look.