Advice needed re Disco with various problems

Hi everyone.
I have been looking at this site for a couple of weeks and I've gotta say you guys certainly seem to know your stuff.
I recently bought a 1995 Series I Disco 3.9 V8 Auto (LPG).
Now here's the problems, when running on LPG it had a tendency to backfire throught the LPG system (dangerous I know). I changed the plugs, lead,cap and rotor arm and the problem went. However it still seems to be hunting on tickover and performance is crap compared to petrol. I contacted the installer who said that he did not want install this system(MG Autogas) but the previous owner insisited, not really suitable for V8 apparently. He also advised me that the car had an auto gearbox problem which makes it jump out of gear when hot. He's bloody right I have noticed this now, only when braking or taking your foot off the accelerator suddenly. So I think that I may have a dog here, I paid £2800 and it's only done 69000 though.So I manage to live with these issues until I can afford to fix it properly. Have spoken to one LPG place who can change part of the system for about £300 upwards and also have another guy who thinks that he may try a regulator or something first. My local mot station let me check the the emissions on both petrol and gas and it seems that it is running too lean on gas. Now the rear electric windows only seem to work when they feel like it too. As my purchase was proving to be irritating I thought I'd be nice to it so I purchased some second hand genuine L/R sidesteps. Found a bargain on ebay only £40. Guess what, I got home and there were no mounting brackets, seller hasn't got his anymore and L/R don't supply seperately. Aftermarket step brackets are different apparently.Think I've found some brackets via an online breakers yard search, he wants £20 so I hope they're the right ones. Should be amusing fitting these myself.
Anyway am I moaning enough ? Despite all of this I absolutely love this vehicle (I only bought it after I injured my back and needed a vehicle that would give me support)

So does anyone have any advice on my LPG,autobox elec/windows or sidestep problems ?

Thanks for listening.

Brian

A multitude of problems indeed.

LPG. I know lots of people who have chased many problems with lpg systems. You said the MOT station rekon its lean on gas, did they adjust it for you? This may be a good place to start. A lean mixture setting could cause the engine to hunt at low revs, it will also cause it to run hot making the problem worse due to some of the gas which is supplied being evaporated by the excess heat. But get someone who knows what they're doing to adjust it.
Also if you are told by several places this system is not good for a V8 you may well be advised to start again. These set-ups can be tempremental and if it isnt right for the car it will never work.

I've not heard of an auto jumping out of gear before, but if it only does it when its hot, i would start by changing the gearbox oil. Nobody seems to remember that come service time, and oil does break down through use like everything else. Problems caused by old oil will be more noticeable when its warmed up and thinned out.

The rear electric windows. You have got the window lock on have you? If not this will be a dodgy contact. Next time they stop working try operating them from the rear door, if they work from the back but not the front, or vice versa, this will tell you a switch is on its way out. If they dont work from either end the problem is likely to be in the door.

If the brackets dont fit the side steps, or car, or both, take the lot to a fabricators. Say "I want these (side steps), on there (the car)" They should be able to hammer bend and weld something to hold them in place easy.

Thanks for you reply Stodd

The Mot guys didn't adjust as they don't touch LPG. Also the garage that told me about the auto problem, well I assume that they would have replaced the oil. However I will do this. Window lock not on, unable to operate rear windows from front or rear when the problem occurs.
I like your idea re sidesteps may try this if the brackets are no good.
Thanks for your help.

Anyone else got any ideas ?

Boh, autobox, also try taking off the center piece on gear selector and check the 6mm circlip is in place on top of the plastic half barrel shaped lifter. it did it on mine THEN stuck in gear!!!!!!!!