Hi all...new to largos, have a couple issues! Any help?

[Skip20xx]

Hello all, I have not long brought an n reg highway star, 2L diesel. Pulls like a train!
It is fairly noisy(like an old transit!) is there anything that can be done to quieten this?
Also when in D or R and stopped at lights, traffic and parking, or just on the foot break when going into gear the largo seems to bunny hop! The Rev counter jumps and makes the largo jump/Rock like crazy! I use the 'heat' button to stop this, and it works most of the time as it settles the revs. But this does not always work! I've had new fuel filter put in and injectors checked, all ok now as it was clogged with dirty diesel, but the problem still persists!
Also I have the issue of juddering (possibly car not deciding what gear) at the speed of around 50mph. I have had the gear fluid checked and that is all fine.
I haven't got a lot of money as I am going through operations and got the largo to help, being automatic. But bar basically a whole engine rebuild, is there any other solutions people can come up with?
Or is there anyone nearby that could check her over? I want to take her to France next year without any problems!
I am in somerset, UK
Thanks

[tttonyyy]

Welcome to the forum.

When you say "jumps" does it do this once or does it keep seeking up and down?

I'd try unplugging the crank position sensor or #1 injector lift sensor and see if it goes away at all.

The only time I've made mine hunt up and down constantly is from doing the quantity adjuster "hammer mod" and getting the quantity adjuster too far in the direction of the front of the vehicle. I took a vid - is it like this? https://www.youtube.com/watch?v=TfOWSxvHrkk

I've had mine bounce up and down in a cycle sometimes when sitting at lights, but then it only does this rarely and it may be because of the variation in cetane number of my homebrew biodiesel that it runs.

If it's not a cyclic jumping, what does your engine do if suddenly electrically loaded (IE, wind both electric windows up when they're already up) - this may cause a single jump and dip in RPM which I believe comes back to quantity adjuster wear. But can't say for sure.

[tttonyyy]

50mph hesitation may be the EGR valve, try unplugging all three electrical vacuum solenoid connectors under the passenger seat and see if it stops.

[Skip20xx]

Thanks for the replies, I'll check all in a bit
By 'jumpy' I'm mean it keeps on seeking up and down until I put it into neutral, but sometimes using the heat button helps settle it down

[Skip20xx]

Where would I find the erg valve and how could this be sorted if that's the issue, and wheres the solenoid connectors?

[tttonyyy]

The EGR valve hangs off the back of the engine on the passenger side, look under the passenger seat for a UFO type thing with a rusty loop of tube (rusty because it gets hot with exhaust gas).

The UFO bit is a vacuum actuator, there is a rubber tube to it that, when sucked on, opens a valve underneath that lets some exhaust gas into the inlet. This happens when the engine returns to idle, and it reduces NOx exhaust levels (although this is not tested as part of the UK MOT test).

To encourage the engine to take a gulp of exhaust gas there is also a butterfly valve in the air inlet, which is momentarily shut as the engine returns to idle, restricting the inlet air flow at the same time as the EGR valve opens, so the engine will suck in more exhaust gas at that point.

The inlet butterfly and EGR valve are all controlled by solenoids in the vacuum system, and these sit on top of the chassis section right under the passenger seat. Disconnecting all three them electrically disables the operation of the EGR entirely - fine for an experiment.

The usual issue with EGR valves is that they jam up with coke from the exhaust so if it behaves the same with the vacuum system disabled that indicates that it needs a good clean inside.

[Skip20xx]

Thanks tony, I'm not mechanically minded so ill show what you've wrote to the garage, hopefully he knows what you mean haha.
How far away are you, could do with you having a look over as ou now what your talking about!
Have you created a mod for the injectors/solenoid wires that may help with my 'jumpy' and 40-60mph issues?

[Skip20xx]

And If the erg needs a clean out, how do I do this?
Do you have any ideas why when In gear but stopped or moving without exceleration the Rev counter goes nuts, jumping up and down, sometimes causes stalling?

[Skip20xx]

Iv unplugged the 3 solenoid connectors, but still rocks the van when stood still, revs go up and down like it wants to pull away, then drops as if it wants to stall. But it doesn't always do it, I found using the heat button helps settle the revs down most of the time.
When trying o check the issues for the rocking/jumpyness, do I need all three solenoids unplugged or just the 1st one?
Mine are coloured green black and brown if this helps

[tttonyyy]

I don't think EGR will affect the bouncing engine issue but would hesitation around 50mph.

I do think you need to code read it to see if #1 injector lift sensor is OK.

Failing that I would be tempted to hammer mod the quantity adjuster towards the rear of the engine a bit.