Need help with Vauxhall Combo and Koltec system for a friend

[sorcerer]

If the moderators happen to be looking, I'm asking this question on behalf of a friend who's been trying to register for the forum for the last few days but with no luck - any particular problems with the board preventing registrations?

Anyway, this is what he asked me to post:

Help required - I have a 1999 V reg Vauxhall Combo 1.4 petrol factory fitted with a Koltec type number VG392. My problems started a couple of months ago when my van took longer and longer to change to LPG. It used to backfire a lot then revert back to Petrol and now when I flick it onto LPG I get the normal 4 clicks but it fails to switch over no matter how long the van has been running.

I have just changed the plugs and still have the same problem, any help will be very much appreciated. I am a novice when it comes to cars but still able to follow procedures if need to.

Thanks

Anybody got any ideas or suggestions I can pass on to him please?

Cheers

[pjpj]

It sounds like a fuel restriction.

Confirm whether EGI or GSI from the images below.

Has any work been done on the coolant and have levels been checked. I'll take a punt and say the vaporiser needs cleaning out and re-building but just a guess at this point.

[sorcerer]

It sounds like a fuel restriction.

Confirm whether EGI or GSI from the images below.

Has any work been done on the coolant and have levels been checked. I'll take a punt and say the vaporiser needs cleaning out and re-building but just a guess at this point.

Thanks pjpj. I've given my mate a link to the post so that he can read any replies himself but if he needs to respond he'll have to email me and I'll copy it to here, so it may be a bit of a slow process Cheers mate.

[sorcerer]

OK, next message from my mate:

First of all thanks for your help it is very much appreciated and now for a few answers to your questions on further inspection it looks to be a EGI System Layout, I do remember having a few issues with the coolant my van stopped working on LPG I opened the bonnet and on close inspection found the Koltec was frozen and once I topped up my water things went right (lesson learned always check your water). I hope this added information helps.

Thanks again folks

[rossko]

So is it working now or not, has he checked the coolant level this time or not?

[sorcerer]

So is it working now or not, has he checked the coolant level this time or not?

Sorry, had to drop my wife off at the pub for the ladies darts team and have my tea - next installment is:

Hi I have checked the coolant levels and they seem okay, at the moment the van runs well on petrol but will not change over to gas, thanks

[pjpj]

I'll send you the EGI fault log sheet by PM.

You need to check for airlocks in the coolant pipework to the vaporiser then, if the vaporiser is higher than the pipework then this is a possibility.

Test the solenoids on the solenoid valves for open or short circuit. One just before the vaporiser, this is prime suspect for failure, and one near the tank. If the solenoids are good it is possible, especially at this age, the valves are stuck but repairing those requires some dismantling.

Quite often if the solenoid is faulty then it can be seen the plastic casing is split.

Basically, you will likely need to find out how far the gas is getting. Is it getting to the vaporiser? Is it getting through the vaporiser? Is it getting through the EGI distributor?

If after testing the solenoid coils they prove OK and the valves can be heard working and no other fault is showing I would start by loosening the 'Out' pipe, the easiest, from the vaporiser and seeing if gas comes out of there. Be safe.

[sorcerer]

Thanks very much pjpj, much appreciated.

[sorcerer]

OK, next installment from my mate:

Hi, I have done the diagnostic test and no errors were shown, the solenoids seem to be fine. I am a little unsure how to check for airlocks in the coolant pipework to the vaporiser which pipe is this is there a diagram? I presume once I do identify it I undo it and let the water flow through similar to bleeding a radiator? thanks again for your time and help.

Cheers folks

[rossko]

Start from cold, put your hand on it and see that it warms up.

"Will not changeover" needs clarifying - does it try, but splutter or stall? If it tries within a reasonable time after startup, it won't be an airlock.

See the previous hints about finding out how far the gas is getting.

[sorcerer]

Thanks Rossko - here's another message he asked me to pass on:

Hi

Latest on my LPG problem, I did the diagnostic check and all was well no blinking and no errors shown, I then removed both water pipes on the Vaporiser and saw that water was flowing through both pipes. Next I I unscrewed the gas connector and saw the gas was reaching the little unit which attaches to the vapouriser.

Checked the solonoids and they click on and off no problem, so I then decided to take it for a test run it took quite a while but eventually it changed over to gas it runs for a mile or so then switches itself to petrol so I switch the rocker switch to off then on again I get the solonoids clicking and we are back on gas. This seems to be behaving the same as before when it would not change over at all.

I have just noticed that I have a hole in my middle section exhaust pipe and have booked it in to be replaced tomorrow, can this cause the engine not to run on gas? suggestions and ideas welcome.

Thank's again

[rossko]

Nah it won't be the exhaust.

What help is your friend actually expecting? It's gone beyond a "top this up" or "press that" fix. He's most likely going to have to strip and refurbish the distributor and/or vaporiser. But a smart first move would be to plug in a live OBD reader and see what the engine management thinks.

[pjpj]

Just for interest, how many miles has this got on the clock. It's not uncommon for Combo vans to have traveled to the moon and back with their LPG system still running.

[sorcerer]

Latest installment chaps:

Rossko - he's not got an OBD reader but is coming round to use mine sometime around lunchtime tomorrow - we'll have more info for you then.

pjpj - The van has done just 87,000 miles.

Mods - any reason as to why he can't register for the forum himself? I don't mind being man in the middle but if I have to go anywhere it's delaying replies.

Thanks everyone.

[sorcerer]

Turns out that my code reader won't work on his van, or there's something wrong with the OBD on the van - my reader works because I tried it on my car, but it says 'connection error' or 'lookup error' or some such thing on his van, so no further forward yet folks.

[rossko]

Looking back, i guess that's not too suprising on a 1999 car.

Roll up sleeves and muck out distributor, as the one of two suspects least likely to end in tears.

[pjpj]

I concur.

There is a DFCO valve on the bottom of the distributor that can fail preventing any LPG through too.

PM sent.

[sorcerer]

As always, thank you very much guys. I don't know when he'll get round to doing it now that it's weekend. I know that we're both at the pub tonight, and I've got things on in the morning so even if he sends something to me I won't be able to get it up on here until the afternoon, so apologies that it's going to drag on a bit.

Cheers