Hi

I am considering an LPG conversion on my MK2 VRS TFSI. Has anyone else converted and any useful information you can give me. Still not fully made up my mind, although doing 20k miles a year, it makes sense. Don't even know whether it is possible yet on my model, although just emailed a conversion center to find out.

At first you should consider the conversion price. For FSI engines it's usually ~2k pounds and I guess that it's more or less the same for TFSI. Simply calculate how many years it take to pay for the system itself...

I like LPG systems but not for these expensive direct injection engines.

I thought it might be around £1500. Have to wait and find out from the garage I asked that do these conversions what price they come back with. It it's closer to £1500 it should start paying for itself after about 1 year. 2 grand I must admit is a lot to pay out. Looking at it long term, it's still worth the £2k outlay, it's just hard to part with that much money up front. I do intend to keep this car a number of years mind.   

lpg is a dry fuel and can cause valve recession in the cylinder head resulting in compression issues

 

had it fitted on a 2001 mondeo did about 83000 miles then put a genuine ford log head on it along with flash lube it. ended up doing 210,000 miles and plenty of saved ££££ on fuel

I did some rough calculations and it seems that in your case the savings are ~1k pounds per year. Yeah, with your mileage it makes sense.

Be aware of some LPG disadvantages as well - LPG tank needs place (usually they are fitted in the place of spare wheel which needs to be put in the boot), LPG tanks usually aren't large so you might refuel every 200 miles or so etc.

My brother runs LPG on a couple of his (none-VAG)  vehicles. He says so long as you're accepting of the fact you'll probably have to change a cylinder head sooner or later, it's great. Me, I know if something were to go wrong, I'd be a long way from home when it did, so I don't chance it.

Edited 16 November, 201510 yr by StevesTruck

Older LPG system used to be nasty as they could do much harm to the engines.

The new systems are way better. My colleague has installed LPG on his Toyota and after 100k km he hasn't got any problems and he's not the only one.

jevpls- I used to hear years ago, that LPG can over long term damage engines. I also understand that is now a problem of the past, as the technology has improved. Where they need to put the tank should not be a problem, as my car does not have a spare wheel, so it will go in the wheel well. The small tank should also not be a problem either, as there is an LPG station no more than 600mtrs from where I live. 

mike4scuba- a fellow scuba diver by your title. Are you saying it's now a good system, or steer clear and live with the price of petrol? Not sure what a ford log head and flash lube means? 

Oh decisions, decisions, not sure what to do. Have to get more information to base my decision on. If it is a safe system, it might just depend on what price the garage quote for fitting it.

Most of the Taxis (and there are hundreds) in my area run LPG.  They log up to 400,000 miles without valve recession issues.  They're all tightwads so i can't imagine them using a flash-lube system.

Have now got the quote back from the garage for the LPG conversion. You were right jevpls, it is real expensive for the direct injection engines. They say only "Prins" do a dedicated kit and that works out at £1850 + VAT. Yes if I keep the car over 2.5 years it will start paying for itself, but it is one hell of an initial outlay. 

Have now got the quote back from the garage for the LPG conversion. You were right jevpls, it is real expensive for the direct injection engines. They say only "Prins" do a dedicated kit and that works out at £1850 + VAT. Yes if I keep the car over 2.5 years it will start paying for itself, but it is one hell of an initial outlay. 

 

The Prins "liquid" injections looks interesting and efficient. Be careful though - later EA888 tsi engines  ( I think this is fitted to the VRS) has two banks of injectors (direct and port) . The liquid injection system uses the same direct injectors not sure about with the port injectors though

Edited 19 November, 201510 yr by bigjohn

The Prins "liquid" injections looks interesting and efficient. Be careful though - later EA888 tsi engines  ( I think this is fitted to the VRS) has two banks of injectors (direct and port) . The liquid injection system uses the same direct injectors not sure about with the port injectors though

Port/direct injection only became available with the Gen3 EA888 on the Octy3.  As this is an Octy2 sub-forum the OP doesn't have to worry about that

Port/direct injection only became available with the Gen3 EA888 on the Octy3.  As this is an Octy2 sub-forum the OP doesn't have to worry about that

 

Is the latest EA888 still chain cam or like the new 1.4 is it now belt?

 

Port injection (only used under certain circumstances) should hopefully recude/stop carbon buildup on the valves

Edited 7 March, 201610 yr by bigjohn

Is the latest EA888 still chain cam or like the new 1.4 is it now belt?

 

Post injection (only used under certain circumstances) should hopefully recude/stop carbon buildup on the valves

Still chain.

I know there have been issues with the tensioner on the Gen2 model.  Hopefully fixed now.

 

Post injection?  Autocorrect for Port?  Yes, you'd hope the inlet fouling would be reduced.

 

 

Still chain.

I know there have been issues with the tensioner on the Gen2 model.  Hopefully fixed now.

 

Post injection?  Autocorrect for Port?  Yes, you'd hope the inlet fouling would be reduced.

 

Oops - yes post = port!

 

There have been issues with the chain/tensioner on the 1.2/1.4 as well - hopefully sorted now on later versions - chain/tensioner/sprockets have had major revisions.

Edited 21 November, 201510 yr by bigjohn

Just a word: if I'm not mistaken Prins is a Dutch company, and the Dutch have been fitting LPG systems to engines since about when I started to get some technical interest in cars (= longer ago than I care to remember in detail  ). I only ever heard them rave about the beneficial effects it had on engine life (and their wallet), never about failure. It's still the country to look for 2nd hand vehicles with an LPG conversion.

Last I looked (2y ago), having a conversion done would come in at about 2k€, same order of magnitude as the price quote you got. Still, it might be worth it to look into having it done directly by Prins themselves, I seem to recall they do offer that kind of service.

Th ferry return fare to Hoek van Holland alone could well cancel out any gain, though, and having this kind of work done in a local workshop does have its advantages too.

 

I take it you had a look at LPG availability first? That, combined with the limited mileage of the tanks currently used made me decide not to look for a 2nd hand converted vehicle. Plus the fact that diesel still comes in cheaper at the pump for me, at least for now here in France.

Edited 21 November, 201510 yr by RJVB

Just a word: if I'm not mistaken Prins is a Dutch company, and the Dutch have been fitting LPG systems to engines since about when I started to get some technical interest in cars (= longer ago than I care to remember in detail  ). I only ever heard them rave about the beneficial effects it had on engine life (and their wallet), never about failure. It's still the country to look for 2nd hand vehicles with an LPG conversion.

Last I looked (2y ago), having a conversion done would come in at about 2k€, same order of magnitude as the price quote you got. Still, it might be worth it to look into having it done directly by Prins themselves, I seem to recall they do offer that kind of service.

Th ferry return fare to Hoek van Holland alone could well cancel out any gain, though, and having this kind of work done in a local workshop does have its advantages too.

 

I take it you had a look at LPG availability first? That, combined with the limited mileage of the tanks currently used made me decide not to look for a 2nd hand converted vehicle. Plus the fact that diesel still comes in cheaper at the pump for me, at least for now here in France.

I am still trying to make up my mind whether I want to fork out that much cash initially on the conversion. As stated on one of my previous posts, there is an LPG station just around the corner from me, so frequent filling up will not be a problem. I have also just looked at my accounts to see how much I do pay for fuel each year. It works out at around £3300. That was with a previous car that did about the same MPG as my recently purchased VRS. If LPG is about half the cost of petrol, It should pay for itself well within 18months though. I am still not sure long term, whether LPG will cause any damage to something like the cylinder head of a direct injection petrol engine. Repairs to the engine in the future would cancel out any financial gains I get with the cheaper LPG. What would you guys do??  

If availability is good (within your/my full usual radius, not just around the corner), if the decreased mileage is no issue and you can/I could spare the initial expense, I'd go for the full package, with the injector lubrication.

 

In fact, knowing what I know now about the kind of diesel engine I have in my car, I'd be tempted to convert that engine to LPG if it were possible (and I had the budget for it).

One thing that does put me off a little is the common fault these engines have with the inlet manifold swirl flaps. I have just had a new manifold at 36k miles. The Prins injectors I believe go into the manifold. If I need another manifold in the future, part of the conversion will need to be done again. Another expense. Maybe though, with cleaner LPG fuel the swirl flaps will not so easily start sticking, setting off the engine management light. I have the spare cash by the way, it's just hard spending it!  

I am still trying to make up my mind whether I want to fork out that much cash initially on the conversion. As stated on one of my previous posts, there is an LPG station just around the corner from me, so frequent filling up will not be a problem. I have also just looked at my accounts to see how much I do pay for fuel each year. It works out at around £3300. That was with a previous car that did about the same MPG as my recently purchased VRS. If LPG is about half the cost of petrol, It should pay for itself well within 18months though. I am still not sure long term, whether LPG will cause any damage to something like the cylinder head of a direct injection petrol engine. Repairs to the engine in the future would cancel out any financial gains I get with the cheaper LPG. What would you guys do??  

 

Did you use the same LPG consumption as petrol? Maybe it's different for these 5th generation direct injection systems but before LPG was used like ~20% more than petrol. I suggest you to find out first. It might be important in the calculations.

Edited 21 November, 201510 yr by Jevpls

Did you use the same LPG consumption as petrol? Maybe it's different for these 5th generation direct injection systems but before LPG was used like ~20% more than petrol. I suggest you to find out first. It might be important in the calculations.

Yes you are right, you don't get as many miles per gallon as petrol.Your percentage figure sounds about right. I did roughly factor that in. Wish I could make a decision! 

One thing that does put me off a little is the common fault these engines have with the inlet manifold swirl flaps. I have just had a new manifold at 36k miles. The Prins injectors I believe go into the manifold. If I need another manifold in the future, part of the conversion will need to be done again. Another expense. Maybe though, with cleaner LPG fuel the swirl flaps will not so easily start sticking, setting off the engine management light. I have the spare cash by the way, it's just hard spending it!  

 

The Prins liquid injection system uses the same petrol direct injectors - the fuel supply is diverted from petrol to lpg( still in liquid form)

http://www.environmentallyfriendlycar.co.uk/index.php/gas-conversions/97-petrol-engines-and-gas-conversion/lpg-autogas-and-direct-injection-engines/118-direct-injection-petrol-engines-and-liquid-lpg-injection

 

This is why it looks interesting - this should have a cooling effect on the valves due to the gas vaporisation (latent heat of evaporation) going on just below them -  well before it all goes bang anyway! This could reduce the "welding" effect that causes valve recession and possibly reduce carbon buildup on the valves 

Edited 21 November, 201510 yr by bigjohn

The Prins liquid injection system uses the same petrol direct injectors - the fuel supply is diverted from petrol to lpg( still in liquid form)

http://www.environmentallyfriendlycar.co.uk/index.php/gas-conversions/97-petrol-engines-and-gas-conversion/lpg-autogas-and-direct-injection-engines/118-direct-injection-petrol-engines-and-liquid-lpg-injection

 

This is why it looks interesting - this should have a cooling effect on the valves due to the gas vaporisation (latent heat of evaporation) going on just below them -  well before it all goes bang anyway! This could reduce the "welding" effect that causes valve recession and possibly reduce carbon buildup on the valves 

Cheers bigjohn. I was not thinking clearly when I made that statement. It would still be good to have a member come back who has had it fitted to their MK2 VRS tfsi engine. It would be good to know what experience they have had. Must have another trawl through the internet to see if anybody has, although most good info comes through this site. 

Hmmm, you could have a look on autoscout24.eu to see if anyone already put a car with your engine and an LPG conversion done up for sale, or on spritmonitor.de to check mileages and real-world fuel consumption. Spritmonitor won't tell you what kind of conversion was done, but the ads on autoscout24 should have that information.

Cheers bigjohn. I was not thinking clearly when I made that statement. It would still be good to have a member come back who has had it fitted to their MK2 VRS tfsi engine. It would be good to know what experience they have had. Must have another trawl through the internet to see if anybody has, although most good info comes through this site. 

 

Likewise, I'm keeping an eye on this although I don't think I do enough mileage to justify the extra costs especially as my petrol consumption is far better that I expected anyway  

Edited 21 November, 201510 yr by bigjohn