LPG MPG Suddenly deteriorated

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markie76
Posts: 7
Joined: Sun Aug 08, 2010 4:39 pm
LPG System: LOVATO
Car: BMW 323i

LPG MPG Suddenly deteriorated

Post by markie76 » Sun Aug 08, 2010 4:43 pm

Hi Guys,

1998 BMW E36 323i Coupe auto - LOVATO LPG

I would like some advice on possible causes for my LPG mpg to suddenly deteriorate.

I got my car in May and it was doing around 175mpg to a tank of LPG (200 on motorway)

about 2 weeks ago it dipped to around 140mpg to a tank of LPG.

Nothing has changed on the car.

Any ideas?

Thanks,

Mark.

mak-uk
Posts: 288
Joined: Mon Sep 03, 2007 8:48 pm
LPG System: Prins VSI
Car: BMW 540iA Sport
Location: All over the UK

Re: LPG MPG Suddenly deteriorated

Post by mak-uk » Sun Aug 08, 2010 11:21 pm

Hi Mark,

Common problems on this car include oxygen/lambda sensors and MAFs (air flow meters). Get the codes read on the vehicle and start from there.

Also, when was the LPG side serviced?
Mak
Site Owner
2001 BMW 540i Auto Sport Saloon
~300 BHP; ~320 ft/lbs, Prins VSI system

markie76
Posts: 7
Joined: Sun Aug 08, 2010 4:39 pm
LPG System: LOVATO
Car: BMW 323i

Re: LPG MPG Suddenly deteriorated

Post by markie76 » Mon Aug 09, 2010 11:12 am

mak-uk wrote:Hi Mark,

Common problems on this car include oxygen/lambda sensors and MAFs (air flow meters). Get the codes read on the vehicle and start from there.

Also, when was the LPG side serviced?
Hi Mak,

Thanks for your reply.

You're right, I should check the usual suspects - I had fallen into the trap of just assuming it was something on the LPG side.

Its due an LPG service round about now.

Do you know of any reasonably priced LPG servicers in London or the Surrey/Hampshire area? (apart from Tasso - already have a quote from them)

Thanks,

Mark.

mak-uk
Posts: 288
Joined: Mon Sep 03, 2007 8:48 pm
LPG System: Prins VSI
Car: BMW 540iA Sport
Location: All over the UK

Re: LPG MPG Suddenly deteriorated

Post by mak-uk » Tue Aug 10, 2010 6:07 pm

Hi Mark,

Try Picket Piece Motors (do a search for them) and say you were referred by Mak from LPGinfo. They are around Andover.

That's the only place I know around there.

Let us know how you get on.

Mak
Mak
Site Owner
2001 BMW 540i Auto Sport Saloon
~300 BHP; ~320 ft/lbs, Prins VSI system

markie76
Posts: 7
Joined: Sun Aug 08, 2010 4:39 pm
LPG System: LOVATO
Car: BMW 323i

Re: LPG MPG Suddenly deteriorated

Post by markie76 » Wed Aug 18, 2010 2:44 pm

mak-uk wrote:Hi Mark,

Try Picket Piece Motors (do a search for them) and say you were referred by Mak from LPGinfo. They are around Andover.

That's the only place I know around there.

Let us know how you get on.

Mak
Having driven it a bit since my last post, I can confirm it is something on the LPG side as on petrol it purrs smoothly but switching it to LPG its behaviour changes from having a slight stutter to idling 200rpm below normal to periods of running normally. So it's intermittant, as when its running rough switching it back to petrol and its all fine at the touch of a button. :(

I'll give them PPM a call this afternoon....

markie76
Posts: 7
Joined: Sun Aug 08, 2010 4:39 pm
LPG System: LOVATO
Car: BMW 323i

Re: LPG MPG Suddenly deteriorated

Post by markie76 » Wed Aug 18, 2010 4:55 pm

Phoned 'Picket Piece Motors' and they said "We don't do Lovato" - :(

mak-uk
Posts: 288
Joined: Mon Sep 03, 2007 8:48 pm
LPG System: Prins VSI
Car: BMW 540iA Sport
Location: All over the UK

Re: LPG MPG Suddenly deteriorated

Post by mak-uk » Wed Aug 25, 2010 12:49 am

Maybe try ringing the LPGA (now UKLPG) and ask them for suppliers/workshops who fit that system?
Mak
Site Owner
2001 BMW 540i Auto Sport Saloon
~300 BHP; ~320 ft/lbs, Prins VSI system

markie76
Posts: 7
Joined: Sun Aug 08, 2010 4:39 pm
LPG System: LOVATO
Car: BMW 323i

Re: LPG MPG Suddenly deteriorated

Post by markie76 » Tue Sep 07, 2010 9:46 pm

ok, I took it to Euro LPG in Wembley for the service which seemed very reasonably priced and they said it also included a diagnostic check.

They said diagnostic check was all ok but don't do printouts - can someone confirm when doing diags on LPG systems, do you get a summary printout or something?

I've been using it for two weeks and have the following observations;

* When I first start it up (on petrol) I get a whiff of gas (or whiff of something that smells like gas) through the vent when the fan is on.
* When it switches over to LPG it runs fine.
* When idling on LPG (soon after switch over) it revs at around 900-950rpm (petrol is around 1150-1299 - it's an auto)
* When warmed up, idling on LPG rises to 1000-1050rpm and remains stable.
* When driving on LPG I got a whiff of what smells like gas on 3-4 occassions.
* Early indications are the MPG on LPG may have increased by 10-15% post service.
* Looking at the engine bay, the LPG components look like WD40 (or similar) has been applied but not fully & lovingly wiped off.

Anything else to check/note?

I plan on doing future services myself as I do on the petrol side of things and also getting a diagnostic interface/software for the LPG stuff :mrgreen:

Thanks,

Mark.

mak-uk
Posts: 288
Joined: Mon Sep 03, 2007 8:48 pm
LPG System: Prins VSI
Car: BMW 540iA Sport
Location: All over the UK

Re: LPG MPG Suddenly deteriorated

Post by mak-uk » Fri Sep 10, 2010 12:28 pm

markie76 wrote:ok, I took it to Euro LPG in Wembley for the service which seemed very reasonably priced and they said it also included a diagnostic check.

They said diagnostic check was all ok but don't do printouts - can someone confirm when doing diags on LPG systems, do you get a summary printout or something?

I've been using it for two weeks and have the following observations;

* When I first start it up (on petrol) I get a whiff of gas (or whiff of something that smells like gas) through the vent when the fan is on.
* When it switches over to LPG it runs fine.
* When idling on LPG (soon after switch over) it revs at around 900-950rpm (petrol is around 1150-1299 - it's an auto)
* When warmed up, idling on LPG rises to 1000-1050rpm and remains stable.
* When driving on LPG I got a whiff of what smells like gas on 3-4 occassions.
* Early indications are the MPG on LPG may have increased by 10-15% post service.
* Looking at the engine bay, the LPG components look like WD40 (or similar) has been applied but not fully & lovingly wiped off.

Anything else to check/note?

I plan on doing future services myself as I do on the petrol side of things and also getting a diagnostic interface/software for the LPG stuff :mrgreen:

Thanks,

Mark.
Hi Mark,

Normally, you don't get a print out unless by special request - if they have a printing facility.

In regards to gas smell, that shouldn't really be happening so you could ask them to have a quick check with a gas leak detector.

If the LPG service has been done correctly and all is running right, you Check Engine Light (CEL) should not come on whilst on gas, thus indicating your fuel trims are within normal operating parameters.

WD40 can sometimes be used for leak detection or just making wherever it has been sprayed a bit shiny for a while.

If you want to self-service in future, get to know your system, fuel trim adaptation methodology and also the software for your system.

Regards.

Mak
Mak
Site Owner
2001 BMW 540i Auto Sport Saloon
~300 BHP; ~320 ft/lbs, Prins VSI system

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