Disco 2 - LPG problems

I recently purchased a Disco 2, i drove it back 180 miles of motorway, ran sweet as a nut, really impressed with it. However a couple of days later when using it locally the LPG has started playing up.
Basically it starts on petrol and runs up to temperature fine, but when it switches to LPG it starts misfiring and obviously becomes under powered, switch back to petrol and its fine.
Any ideas?
Also i was thinking of investing in a Nanocom, would there be any issues with it being lpg converted or would the Nanocom pick up faults the same as when running on petrol?

Its now started misfiring when stood still running on petrol, could it be simply a case of changing the HT leads and plugs?

ALways a good start, but more likely to be a poorly adjusted LPG system. The Motronic ECU will adapt to the error short term but over time the long term trims will creep out leading to ropey running on both fuels. Get your self the LPG software, run around on petrol for a good few miles (or get the adaptions reset) then do an auto tune on the LPG.

My LPG experience is old school, open loop - but as you've just bought it number one job is leads, plugs etc. all the basic stuff - then you at least know they've been done - good luck

Ok so i've just got round to changing the leads, 1st thing i've noticed is the coil pack bracket is only held on by 1 pin and that was loose, does the bracket need a good earth through the engine?

D2 coils are powered through the two 3-way connectors on each side, nothing is earthed through the brackets/

Those side connections will bear looking at, our son's D2 lost one cylinder in France in 2014 and it was a dirty connection on that plug on one coil, but he had done over 1000 miles out there before it just would not fire on that cylinder as we started out from Carpentras to return to the Nancy area.

Peter

Ignition system in tip top order is essential, i had problems with mine running ok on petrol but sh1te on gas and after leads, dizzy cap , rotor arm and plugs plus a clean out of the gas reducer and filters it was sweet on gas, sadly now it refuses to fire up but that is another matter completely

OK i finally got round to changing the leads. Its still misfiring. My nanocom has arrived too, i'm getting the following faults;
P0134
P0300
P0307
P1000
P0305
On petrol it only misfires on cylinder 7 when idling, rev it over 1200 rpm and it runs fine on all cylinders.
On gas it misfires on cylinder 5 when idling, and cylinder 2 & 5 when at 2000+ rpm

Any suggestions?

Check clean and gap plugs @ 0.8mm and try again

cooltide said:

Check clean and gap plugs @ 0.8mm and try again

Click to expand...

I've fitted all new plugs, they are all set at 0.8mm

Pull plug 7 and double check it plus check contact isn't loose. As for the LPG it's all covered above but it needs to run right on petrol first

cooltide said:

Pull plug 7 and double check it plus check contact isn't loose. As for the LPG it's all covered above but it needs to run right on petrol first

Click to expand...

OK i'll check it in the morning, thanks.

What plugs?

I found NGK seemed to work best

We use Champion Double Platinum OEM plugs OE138, or RC11PYPB4 which are the original recommendation.

We bring them back from the 'states when we go over on holiday.

We also find that gaps increase on LPG due to the extra heat distorting the movable electrode.

Peter

listerdiesel said:

We use Champion Double Platinum OEM plugs OE138, or RC11PYPB4 which are the original recommendation.

We bring them back from the 'states when we go over on holiday.

We also find that gaps increase on LPG due to the extra heat distorting the movable electrode.

Peter

Click to expand...

I am using these Champion plugs, brand new. I've checking its sparking and its fine, i even swapped plugs from a different cylinder just to be certain, its still missing on cylinder 7 when idling.

One thing i did notice is there was a bit of oil on the plug when i removed it from cyl7, not on the electrode just around the base of the thread, there is no obvious signs of oil on the outside of the head so it must be internal?

Also the exhaust is blowing on the manifold on the same side, would this cause an issue, as one of the faults on the Nanocom is P0134 - ''Lambda sensor upstream catalyst bank 1 drive cycle C''

test compression, not sure what the Rover V8 is like, but some engines get valve seat wear with LPG, normally Fixed or repaired daily lumps.

But I ran a GM V6 for around 80,000-90,000 miles on LPG

I gave it a good run and it runs fine on petrol, the problem with LPG was the pipe from the gas valve for cylinder 6 had collapsed inside, swapped it and its running sweet.