I own a 04 Transit running the factory fitted Necam GSI system.
The problem to date is that about three days of running on gas the van refuses to switch onto gas. It runs like a bag of hammers every time the dashboard switch is pressed. The vaporiser clicks and the green indication comes on steady but the van runs like a bag of hammers whilst trying to rev it. The next day I have none of these symptoms and the van runs 100% on gas for another 3 days.
I have done some work to try to rectify this problem. I changed the two in line filters, you could hardly blow through them. I also fitted a new kit to refurb the distributor as well as cleaning it.
I have read the vans petrol ecu with a code reader, and fault code P1131 came up ( heated oxy sensor HO2S cct low variable Bank 1 sensor 2 ). I then changed the rear o2 sensor in the exhaust.
The van ran on gas for a couple of days and then it would not switch to gas the same symptoms as above. this time I let the van get up to working temperature and then switched to gas and it did. After travelling about 10miles I stopped the van to do a job for 10mins. I jumped back in and the van went onto gas for about 3miles. I noticed that the green indication on the dash started to flash. I then pressed the switch several times back onto petrol and then gas. On all occasions I did not hear any relays energise or the vaporiser click whilst pressing the switch. I stopped the van a few miles down the road and turned the ignition off for about 15seconds. Restarted the van and the vaporiser clicked and the van then run on gas with no problems.
I've had the code reader on today in live mode. I noticed from starting up the engine I was not getting any voltage levels from the two oxy sensors for about 5mins from starting the engine from cold. After that time both oxy sensors showed a voltage on petrol. The van then switched over to gas the 1st sensor dropped out and the second sensor started to read a voltage. This is what I would expect to be right.
I have noticed a few times on the code reader that the 2 sensors showing voltage whilst on gas. Is this correct?
I also read the codes again and it is coming up with P1131 lack of HO2S11 ( switch sensor indicating lean ). I also noticed the engine was hunting slightly on Petrol. I have had new HT leads recently, and one new coil pack. The plugs where changed about 3000miles ago as well as the other coil pack.
The other point I noticed on gas was the engine revs kept at 1200 rpm when coming to a stand still. You could see the rev counter try to drop, but it could not. The rpm/ lamba sensor was renewed 2 years ago.
That's all I can think of for now. Can anyone shed some light on this niggling problem please.
Cheers
Veeman

Why would you think that? Ideally the sensors will behave exactly the same on either fuel. I would say the fault codes are telling you that it's wrong.

Did you clean the solenoid plunger when fiddling with the regulator? Sounds gummed up.

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www.blazegas.com

Shouts 'gummed up solenoid' to me too.

Sorry I made a typo error in my original listing. I cleaned and fitted new seals ect in the distributor. I have not touched the vaporiser/ regulator at all.
Do you think this solenoid is still sticking?
Sorry to mislead you. I will alter my original post.
Thanks for the info.
Cheers
Vince

While your there if you have the distributor it isn't GSI its the EGI system. more basic but that's probably a good thing as the gsi injectors are problematic anyway.

It should be fairly easy to remove the solenoid and test - as a test measure only if you remove the plunger and reassemble this will prove if the solenoid is the problem or not. If the problem goes away strip and clean that section out.

You mention it hunting slightly on petrol - I'd try also removing the vacuum line from the vaporiser and plugging it - if this stops the hunting on petrol then it suggests to me you have a leak in the diaphragm inside the vapouriser (there could be a vaccum leak somewhere else if it doesn't stop). Have a look at the vacuum line itself if it does stop I've found mine seems to have started falling apart near the vapouriser when I've been replacing the clutch and suspect this is why i get a random cutout when its cold.

I had an ex environment agency van in the other day, the vac pipe between the manifold and the reducer had imploded on itself. And the pipe had promptly split next to the manifold outlet.

Currently taking the solenoid out of the vaporiser to clean. Will check all the vacuum pipes whist I'm there. It's not much that is causing this problem. It is just putting my finger on it, that's the problem.
Thanks for the info and your time.
Cheers
Veeman

have a look at any of the t-pieces on the vacuum lines whilst your there - ford ones have a habit of developing holes in them which would also cause your hunting issue.

Had a look at the vaporiser solenoid. Looked a little gummed up, so cleaned it as well as the housing it sat in. Whilst blowing through with brake cleaner in one of the solenoid ports a small piece of muck was flushed out. It was the port between the filter and input from the tank.
I then put it back together and had a look at the vacuum hoses and joints. All the plastic/rubber pipes where fine. The joints where alright. I did notice one pipe under the throttle body plastic was just hanging on about a quarter of an inch and slightly to one side. I pushed this home firmly.
I then started the van, and ran sweet on tick over. I did not take it onto the road. Whilst the van was running about 5 mins it cut out on gas. Then every time the van vaporiser solenoid cut in the van stalled. This happened for about 5 times when going over to gas. On the last time on going to gas the solenoid cut in but at this exact time I pushed down on the accelerator. The van then switched to gas and ran fine. It then would switch between gas and petrol no problems. Will run it out on the roads and see what else happens.
Once more many thanks for your suggestions.
Cheers
Veeman

Took the van for a run today. Switched to gas no problems and ran for 2 miles. Came to a junction, ready to pull away and van cut out. tried for the next 2 miles switching to gas, van ran like a bag of hammers whilst keeping the accelerator going. Switched van off and tried to start and once more soon a solenoid cut in the van stalled. Drove another 2 miles and van hesitated and ran fine on gas. I noticed whilst on tick over the vans rpm was at 1200. It was a fast tick over and would not come down to 900rpm.
Could this fault be linked to the RPM/ Lamba filter?
Could this filter be breaking down when it get's hot.
Any one got any thoughts.
Cheers
Veeman

i don't think the ford implementation even has the rpm filter afaik - I gather they have a different ecu that replaces the standard petrol one rather than sits along side it.
I'd have a look at the vapouriser pressure if i was in your position (its reached the age of it being likely it wants a rebuild). The only other diagnosis tool i can suggest is removing the plunger and seeing if its any better in that state - if so then its either clean the solenoid again or replace it (it may be weak rather than sticky so cleaning may not be the answer).

I took this very informative post from one of Edwards replies Edward (MobileLPG) a while back. If you are in his vicinity it would be worth your while getting him to take a look at it for you.

Hopefully this will help you. >

You say you have changed the RPM filter by the ECU, this normally causes the engine to refuse to run on gas at below 3,000rpm, and run like a bag of nails above 3,000rpm (the LPG computer cannot work out the revs basically and this rpm filter just feeds the rpm signal into the LPG system...It also diverts the lambda signal from the petrol ecu to the gas ecu)
The Mk6 Transit from 2000 to around 2006 all have the EGI system with distributor.
I maintain a number of companies fleet Transits and the faults are always the same-

DPFE sensor- this sensor tells the ecu whether the EGR valve has opened as it should have, with no signal from the DPFE sensor the ecu will open the EGR valve further which causes a lean mixture and rough running on gas.....I have replaced so many of these now that what initially was a nightmare job (fixed to the back of the engine) is now literally a 10 minute job providing the exhaust has cooled down.
This sensor being faulty would give you a fault code P1402, most garages read this as an EGR fault and replace the EGR valve but trust me it will be the DPFE sensor not the valve itself....the best way to test for this is to disconnect the EGR valve solenoid, if the EGR cannot be opened, even though you will get a new fault code, it will eliminate this as your problem.

RPM sensor- As mentioned above this causes the van to massively overfuel and will not maintain any revs unless you force it above 3,000rpm and even then it will splutter and cough.

Faulty switching relay- when the vehicle switches to gas it just makes 4 relays go open circuit to kill the petrol injectors, a few times I have seen a misfire on petrol but fine on gas, this is what happens when one of these relays sticks open, on the other hand if one isn't cutting off the petrol injector you would have a nasty misfire through overfuelling on one cylinder that isn't as noticable at higher revs (simple test, stethoscope the petrol injectors when running on gas)

Faulty stepper motor- Randomly cutting out when slowing to a junction, not sure if this is the stepper motor closing too far but replacement has sorted this a few times but it is rare.

Water logged coilpacks - water runs down the screen and creeps past the rubber seal at the bulkhead and makes its way past the coil pack cover seal, the front coilpack of the 2 then goes faulty and causes a misfire, usually only on gas due to the nature of gas needing a strong ignition

Faulty vacuum pipe to LPG MAP sensor/regulator- if you look on the front of the regulator there is a vacuum pipe attached, this runs up the bulkhead and then tee's, one side goes to the MAP sensor located in the far corner of the bulkhead, the other side goes to an elbow fixed on the inlet manifold. This elbow over time becomes really mushy and can literally just be lifted off the nipple on the manifold.
The problem with the pipe being damaged or lifted off the manifold is that this pipe (well the vacuum) varies the pressure at the regulator, with no vacuum the LPG pressure going to distributor will be over 1 bar, however without the pipe the pressure will be around 1/2 bar, if the regulator is seeing no vacuum it will effectively act as though the engine is under load and cause a higher gas pressure at the distributor and over fuelling, at higher revs and under load this wouldn't mater so much as there would be little vacuum anyway but damage to this pipe will cause major problems at low revs/load.

Clogged LPG distributor- This is the No1 fault with these systems, because the distributor feeds gas via little V grooves (smaller section exposed for lower revs and larger section exposed at higher revs/higher load) if the V grooves are dirty then you get a low speed misfire, at higher revs there is more area exposed for the gas to flow so it is less of a problem but at lower revs the gas flow is restricted and causes the problem you seem to be having...this is such a common problem that I strip and clean the distributor on these EGI systems as a routine part of the service.


Right the Necam/Koltec system is a good system but not without its faults, however yours do not fit the 'standard' faults that I see every week.
I have never had one with a faulty ECU yet so would be surprised if your ECU is faulty.
If you are getting the orange light above the switch but no click from the solenoids there are a number of things to check-
Firstly, is the green light flashing in the instrument panel? if it is then it means it is waiting to switch over but has yet to have a suitable signal from the temperature sensor on the regulator, if this has failed (or no water is flowing throught he regulator) then it will never switch over, however you would still get the solid 'clunk' from the rear tank solenoid as it primes the system regardless of temperature.
The next thing would be the main fuses, on the passenger side of the dashboard there is a tray with a cup holder, pull this out and you will see one of the main fuseboxes, to the right of this fusebox all on there own are 2 x 7.5amp fuses (small brown fuses in a seperate holder) check these as one powers the electronics and one powers the solenoids.
The next things would be the wiring to the rear solenoid/tank, looking underneath the vehicle there will be next to the tank a wiring loom that goes to a connector (attached to the chassis rail) this is the live, earth and fuel level signal wire, this connector can corrode and cause the fuse in the dash to blow.
The next power area to check would be the relays under the steering wheel part of the dash, up above the accelerator pedal is the LPG ECU but in front of this will be a row of 5 black relays, the one on the left is the main changeover relay, the 4 to the right are all the petrol injector relays, when power is applied to these from the relay on the left they all go open circuit and kill the feed to the petrol injectors.
If the relay on the left either isnt receiving power from the fuse, or is dead then the system will not even attempt to switchover.

_________________
Regards

PJPJ



To help identify your Vauxhall LPG model, go HERE

Thanks for that reply PJPJ. I have read that post somewhere in the past whilst looking at the internet sites. The trouble is I would love somebody to take the van to, to have a look at. The problem is I'm in the North East in South Shields. I have phoned a few companies requesting if they can have a look at the necam system. Soon as necam is mentioned to them, they avoid it like the black death.
So is there any where near South Shields that is reasonable travelling distance that are happy to have a look at a necam setup?
Jumped into the van tonight and ran on gas for 4 miles with no problems. Happy days BUT!!! for how long.
Cheers
Veeman

?

No but I will look him up.
Thanks for the info.
Cheers
Veeman

Autogas2000 in Thirsk are experienced on the Koltec systems.

http://www.autogas.co.uk/autogas2000-te ... upport.htm

_________________
Regards

PJPJ



To help identify your Vauxhall LPG model, go HERE

PJPJ thanks for your reply. Have dealt with this company for bits in the past. Will give that lead a look into as well.
By the way the van has reached 2 days and no problems yet. Now I have put the kiss of death on that one.
Cheers
Veeman

I replaced the factory fit system on a Transit with a new OMVL Piro system last Sunday...

Owner had already spent loads on the factory system trying to fix it himself and taking it elsewhere, he was getting more than a but fed up of it! I only did a few checks on the factory system, which was working OK when I checked it (sods law), but the owner still asked me to take it all off and put a new system on without doing a longer diagnostic!

Had the Piro in stock because I bought it with the thought of playing about with compensated mode on a suitable vehicle, never thought I'd end up fitting it to a Transit, might seem a strange choice of ECU but I was out of stock of other 4 cyl systems on the Sunday. Still, nothing wrong with fitting Piro on a Transit and the van runs great now.

I've repaired scores of factory fit systems on Transits, Vauxhalls, Citroens, Volvos etc (Necam Koltec / Tartarini Etagas / Landirenzo IG systems etc) but for every five I've fixed I've probably replaced one with an aftermarket system.

Problem with the factory systems is the expensive and outdated parts, some of which are now in short supply, and the prospect of another part failing soon after any repairs to one part: Rebuild or replace the reducer (a rebuild isn't a guaranteed fix depending on the problem and is time consuming on the Koltec reducer)? Rebuild or replace metering units (broken stepper motor or plunger worn out / broken)? Emulation black box problem? Relays in dash problem? Fix an issue and it's likely another problem will occur that might cost a few bob to sort. The pulsed injection factory systems are even worse than the metering unit versions with one injector costing more than a full set of 4 aftermarket injectors / ECU's and emulator boxes being a common problem on them too. If there's much else besides reducer pressure being wrong it can be a better idea to replace the whole system than mess about swapping expensive factory system parts...

You know a customer is pulling your leg when they tell you all was working well with the gas system just the other day... Then you take a look and the reducer has been removed and replaced with a shunting water pipe. You ask if they've removed any parts or if anyone else has taken a look at the vehicle recently, they answer no to both.... Some customers think that by kidding you all was well just the other day you'll somehow be able to magic an inexpensive cure Like the guy who bought a car at auction with a gas filler mounted in the wing and gas switch on the dash - then came to me saying his gas system was working well the other day but now the switch doesn't light, it might just be the fuse mate. On closer inspection the whole gas system, including tank, minus the switch and filler, had been removed

Simon
Lpgc

_________________
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240

Thanks for the info Simon. I get where you are comming from with the new system. I must confess the factory fit system has worked well over the past 5 years I have had the van. It only stopped once in that time. I traced it down to the rpm filter. When I removed it, the side had a bulge in the side of it. Replaced it and everything was fine.
It is just a small problem at the moment. The van ran fine for 3 days, then after a 12 mile journey. the van cut out and 300 yards I put it straight back onto gas and it ran for another 7 miles. Tonight it went onto gas fine then cut out after 3 miles. It took another 1 mile of trying and eventually it went back onto gas and ran another 8 miles.
Something is breaking down, but as you know it is hard to pin things down. I also understand with mixing new and old parts. It does put a strain on the rest of the old components ( electrical ), hence another fault will arrive eventually.
The van is 10 years old and fitting a new system would not be very cost effective, and I think would not be worth the outlay.
Once more thanks for the advice.
Cheers
Veeman

Veeman, you're welcome.

I don't necessarily think that new parts put a strain on other parts that are older, just that all parts wear and you could spend a good deal of money on new parts only to find that other old parts break soon afterwards...

I removed a factory system last Sunday and supplied and fitted a new system with 2 year warranty for £450 (which given the work involved and the dramas on the day seems very cheap to me now). so how much is it worth spending on the factory fit system? I've repaired loads of factory systems but I usually say pay me for a diagnostic first, if I can fix it with a simple adjustment or repair then you'll be sorted, or if it's going to need anything more than a cheap and basic part let me go on to replace the factory system with a new aftermarket system.

An aftermarket system is much cheaper in parts should anything break after the warranty and will be understood by a much wider range of installers. I find most installers don't have much of a clue how to diagnose and repair factory systems, they charge for 'diagnostics' and might guess at which expensive parts to change, but the customer pays for what isn't necessarily fixed. Anyone can charge for a diagnostic, go through a few motions and state that a very expensive part is broken and some installers do exactly that! Factory system parts are getting more expensive and the supply of parts is running out. The parts can also be confusing - I note some well known companies, some recommended on this forum, sell parts such as stepper motors to fix factory systems but sometimes supply the wrong parts, in the case of stepper motors I've seen them supplied with the correct external design but wrong internal gearing for instance.

Would suggest you check the lambda given the problems you've described... I connect a multimeter up to the lambda output and drive the vehicle under various conditions including checking idle. If the lambda stays rich or lean for more than a few seconds it causes the system to switch back to petrol. If the system stays lean for too long increase the reducer pressure and vice versa. The factory systems do store there own fuel trims, so you've sometimes got to drive the vehicle with kid gloves to keep the lambda flicking and avoid the lambda error that causes the change-back to petrol... for the same reasons you've got to adjust the pressure gradually.

Simon
Lpgc

_________________
Full time LPG installer
Servicing / Diagnostics / Repairs to all systems / DIY conversion kits supplied with thorough tech support
Mid Yorkshire
2 miles A1, 8 miles M62,
http://www.Lpgc.co.uk
Twitter https://twitter.com/AutogasSimon
07816237240