First problem in 200,000 miles on LPG!

[capt jack]

For the first time since my V70 was converted 7 or 8 years and 200,000 miles ago I seem to have a problem with my LPG. The car has a Tartarini conversion, and regulars on here will know already just how good it's been.

I'll get the car back to Autogas 2000 in Thirsk next week, and I'm certain that it'll be sorted out, but this is what happened:

Was driving today on LPG, 50mph, 2,000rpm, or thereabouts, and went to overtake a truck towing a broken-down VW Golf. Put my foot down, past autobox kick-down, to approx 4000rpm, then engine started to lose revs and die. Got the car to side of road, and the engine was still running but only just -it felt and sounded as though perhaps two cylinders were firing, and there was a very strong 'bad cabbage' smell of LPG. Switched to petrol and engine picked up straight away. Switched back to gas and the car ran fine. I tried the same again on a quiet stretch of road, and same thing happened.

The engine was well warmed up - it had been running for over an hour. Outside temp was definitely well below zero, I don't know, but maybe that could affect things? I've only done 80-odd miles since last fill-up, so gas tank is comfortably over half-full.

It was a bit scary though, especially for the guy in the white van who'd just decided that the safest place for him at that moment was three inches from my back bumper! Not sure whether or not he may have needed a change of underwear at this point, but the look on his face in my rear-view mirror was a picture, as I somehow managed to squeeze past the towed Golf! I suppose at least that'll teach him not to tail-gate!

My car has now done just over 200,000 on gas, 256,000 in all. The plugs were replaced 6,000 miles ago, and the LPG filter about 10,000 miles ago. Apart from this incident today, as ever, it's been running absolutely fine.

To my old-fashioned mind it felt a lot like fuel starvation, but one thing does puzzle me, and that's why it didn't swap over to petrol automatically, like it always does when the gas gets low?

When it's sorted I'll post up the outcome of course, but if anyone has any thoughts on what the problem might be I'd be pleased to hear them.

Cheers

Jack

[capt jack]

An update:

Car is booked in with Autogas 2000 on Thursday, so we'll see what the solution to the problem is once they've worked their magic.

I tentatively tried running on LPG for a bit today, but it ran for only a short time then automatically switched back to petrol, so I switched the gas off altogether.

The really painful part was filling the petrol tank for the first time in 7 or 8 YEARS! £50 and it only got to three-quarters full!!!!!!!!!!!!

I can't remember the last time I spent that much in one go on any motor fuel. In fact, if I think back to my pre-LPG days I don't think the tank in my V70 would have even held £50-worth of petrol!

Hey ho!

Cheers

Jack

[capt jack]

Well, as ever, John at Autogas 2000 did the business!

A quick via the PC confirmed a drop in pressure, so with this duly adjusted and the lap-top PC connected to the engine, a quick blast along the by-ways around Thirsk, a few taps on the keyboard, job done!

Although not quite due, a new filter was fitted too.

The cost? Well that'd be telling, but a family fish and chip supper would have cost more!

These pages have seen more than a few tales of woe about bad garages and poor service, but Autogas 2000 are exceptional and over the past 7 or 8 years have always looked after my car brilliantly - from the friendly welcome right through to the always-reasonable bill. Bearing in mind that after the inital installation costs, I typically spend no more than £40 or £50 a year with Autogas 2000 on a couple filter changes, but still the quality of service is second to none.

Running around on petrol these past few days has made me realise just how much I'm saving by using LPG. Current reckoning is that I'm over £2000 a year better off.

So thanks Chris and John.

And if anyone's considering an LPG conversion, then it's got to be worth a call to Autogas 2000.

Cheers

Jack

[classicswede]

What I would be concerned about is the cause of the pressure drop.

I remeber reading your comments on your last service and teh pressure needed increasing then.

Has your system been updated from the AEB013 pressure sensor to the AEB025 sensor? I have upgrade alomst all the installs I did that had the 013 sensor as they proved troublesome. Reading a lower pressure than what is actualy there is one of teh faults they could develop.

If you do have the 025 sensor then it would point to a reducer problem.

[capt jack]

Originally Posted by classicswede

What I would be concerned about is the cause of the pressure drop.

I remeber reading your comments on your last service and teh pressure needed increasing then.

Has your system been updated from the AEB013 pressure sensor to the AEB025 sensor? I have upgrade alomst all the installs I did that had the 013 sensor as they proved troublesome. Reading a lower pressure than what is actualy there is one of teh faults they could develop.

If you do have the 025 sensor then it would point to a reducer problem.

I appreciate what you say Dai, and it does occur to me that the pressure drop must have a cause. And yes you're right, last time (July 2011) the pressure had dropped a bit, this time it had dropped a bit more. I'm not sure what sensor is fitted - is there any way I can tell just by looking?

John seemed to think that the fact that the problem showed up when the ambient was minus 7 degrees C might have had something to do with it.

I am possibly taking a bit of a simplistic view of course in thinking that as it's worked well all this time, and most definitely has been brought back into line today, then it's best not embark on major surgery unless it's definitely needed. It's not the cost of any repairs that bothers me, just that I'd like to be sure it is broke before I fix it!

I can say for certain that the system has performed flawlessly as installed for 200,000 miles. That's a pretty fair record, and if the sensor had been suspect would it have shown up by now I wonder? I also wonder if the system at this sort of mileage is simply showing signs of it's age and mileage?

By comparison I've a few miles on the clock myself now, and I can feel twinges in places I never used to have places!

My plan for now is to see how it goes, monitor the fuel consumption and performance, and be prepared to go back to Autogas 2000 if things do start to go awry again.

I also think that a thermostat change might be due - the gauge gets to 3 o'clock and stays there, but the 'stat has been in for well over 100k, and I reckon the car's heater could be hotter. The dissy and rotor are due a change, and the plugs will be swapped in about 3k.

I'm happy that what's been done today is sensible based on the fact that things were assessed and measured first hand and action taken.

The great thing about this forum, and the biggest reason for being on here, is that knowledgeable experts like Dai are prepared to take the time to read posts and offer comment. Which gives people like me the best of both worlds - the benefit of the skill and experience of the guys who know my car and who fitted the system, plus the unprejudiced view of a leading expert on LPG'd Volvos.

Thanks again Dai for taking the trouble to comment. If, as and when this tale develops then I'll post on here. If other LPG-ers can benefit from the discussion then I'll be very pleased at that.

Cheers

Jack

[Fordy]

Glad to hear its still good

I must book mine in for a replacement filter, in 60k miles I've only had the fairy liquid test on the injectors.

[capt jack]

Coincidental with the running problem on LPG, I've recently felt that the car was taking a bit longer to warm up, and that the heater was not as hot as it should be.

I changed the thermostat - and there's a noticeable difference, not just in the heater, but the engine wamrs up much more quickly, and I'm sure is running even better on gas.

The LPG system relies on hot water from the cooling system to vapourise the LPG of course, so there is a connection between the heat of the engine and the efficiency of the LPG system.

There was undoubtedly a problem with the LPG system that Autogas fixed, but I do wonder if a dodgy thermostat and some freezing cold weather had actually served to highlight the problem?

Cheers

Jack