S80 bi-fuel cuts out on LPG
 

Hello all,

After reading a lot on this wonderful forum about Bi-fuel volvo's stalling and cutting out on LPG, I decided to post a post my self.

My problem looks a lot like all the others here on the forum, with the car running fine on petrol and stalling and cutting out on LPG. So after reading those wonderful picture guided manuals for cleaning the distributor, I took a chance and removed the distributor, opened it and cleaned it, ordered a repair-kit and went to work. It all went great, but the problem is still there.

The big difference being that it doesn't stall, it just cuts out right away. When I start the car with a cold motor, it warms up until it switches over on LPG. Sometimes this works flawlessly, with no loss of power, or hiccups or stalling. The car then runs on LPG for a couple of kilometres before suddenly cutting out.

Right now its at the Volvo dealer, but they don't really know where to look. I have an idea that it must be something electrical (stepper motor or DFCO), but strangely intermittent. The furthest I've driven the car on LPG is about 40 kilometre ( I only own it for about 3 weeks).

I hope to have given enough information to receive helpful tips.
Thank you all in advance!

Kind regards,
Fabian

From that description I would be looking at the inline and tank solenoids.

Thank you
 

Hi Classicswede,

Thank you for your quick reply. I will ask the dealer to look at them tomorrow!

-Fabian-

I've had a 2003 S60 BiFuel since 2007. Your best plan is to find an lpg specialist. I had a new gas distributor at 91500 miles, and by 116000 it was cutting out again, so I had it cleaned out. This was ok until 132000, and the lpg garage replaced the stepper motor. The cutting out is caused by a combination of these two factors. Main dealers will just want to replace the whole distributor unit; if I could start again, I would replace the Necam Koltech distributor with a modern system. I know I'll be going through the same exercise again soon!

Hi Glider,

In a couple of days I will receive a new distributor + steppermotor. The volvo dealer diagnosed a faulty steppermotor, and it is cheaper to buy them as a set instead of separate (at the dealer in Norway at least). Since this is a warranty case from the dealer, I just let them fix it.
Before the dealer could look at the car (the only mechanic who knows about LPG cars was on a holiday, had to wait 3 weeks to get it looked at) I cleaned out the distributor. But that didn't solve the problem, I then called with autogas2000 and a Dutch gasspecialist. Both of them recommended to check the steppermotor, so, having 3 (+ yours) judgements which point towards the steppermotor I feel confident that the problem soon will be fixed.

What would we do without internet forums, haha!

Cheers, Fabian

Like classic swede says look at the solenoids. These run hot and in time can crack their casings, although a crack in one doesn't mean to say it's failed. The inline one is on the side of the vapouriser.

Below is a picture of two Koltec vaporisers showing their solenoid cracks. One is a Volvo one and one was a Vauxhall one i think, but same part.
http://www.volvoforums.org.uk/pictur...pictureid=6368

If it is a Necam/Koltec system then these run fine but many don't know how to properly test them and replace parts willy nilly.

What you really want is to measure the gas pressures. If you're not happy doing this get the volvo dealer to do it for you. On Necam distributors there's a little side port for this. The pressure there should be stable at about 14psi above atmosphere. If it's not go backwards through the system and measure the vapouriser pressure on its side port. That should be stable at about 21 psi above atmosphere. You'll see it shift a little with demand but not much. Also it may overshoot a little when the LPG is turned off.

If the car is stalling or not running at all on LPG then I'd look at the pressure at the vapouriser. As soon as the inline solenoid opens this should immediately jump to about 21 psi.

It'll become more obvious where the fault lies when the car dies on LPG when you look at the pressures.

Some LPG garages will replace the distributor when they don't know what they're doing or cant be rrss tracing the fault. Unless there's some underlying fault Necam distributors don't expire after 91K miles. One by me wanted £500 for a new one! I completely overhauled it with a seals kit for about £15 inc post.

Hi Pete,

Bit of a late reply, but time flies the last weeks. At the volvo dealers I had to wait until the end of July to receive a new steppermotor, so I ordered one from Holland. I also checked the solenoids, but they looked nice and not cracked as shown on the picture.
Now I'm waiting patiently for the mailman to bring a new steppermotor, if that fails I'll get the dealer to check and measure the solenoids.
But first fingers crossed for the steppermotor :)

Thanks for helping!
Fabian

i cured one problem like this by cleaning the inlet valve on the evaporator . It is part of the elbow which lets the liquid gas into the evaporator , it is spring loaded and can go very dry and stick . A dry kind of sediment jams it shut or partialy shut .

Hello again!

Today I finally received the steppermotor. It looks like this was the faulty part since the car now drives like sunshine on LPG.

Thanks everyone for sharing your thoughts and opinions!

Cheers Fabian

Distributor cleaning
 

Hi all,

I've got the same old problem, the LPG was cutting out every 800 miles or so and I could just turn it off and it'd work again after a minute, but now it's more like every 50 miles.

I remember seeing a manual to clean the distributor on here but can't find it, could anyone direct me please?

Thanks!