LPG Discussion Forum

Greetings!

I read your comments with interest re Autogas Experts/Solutions in Corby and Hitchin. I had a 2003 BMW 325i with 41,000 miles converted by them last November.
I do all my own servicing but am no expert on LPG - their installation appears neat and tidy but is not without issues – they certainly are not one of those instal in a day merchants – they took ages to do it!. Believe it or not I went round several installer before choosing them.
At the 1000 miles check up I asked them to check the idle – it hunts up and down quite often (especially when first switching to gas) and so its easy to stall the car.
They checked the gas system and said all was ok and that it was prob related to the car’s existing vacuum system or HT having a minor fault which gas finds but is ok with petrol.
eg they were washing their hands of it.

I was annoyed at this answer as it doesn’t help me get the car running properly – normal garages wont touch a problem like this especially with a new gas instal so I decided to investigate myself.
The vacuum system certainly is an issue just reading BMW forums (and I have had the odd Lambda control tolerance fault codes)so I decided to check the whole system replacing most of the air/vacuum hoses as I went and oil separator (which is a problem on these cars). I don’t know anyone with a smoke tester and if I did the cost of having it done I might as well replace all the hoses. I wasn’t keen on trying the starter spray technique of finding faults as you cant reach most of the hoses anyway. So far I replaced air hoses between Maff and inlet and its already made a small difference so I feel this is the right route.

However if it doesn’t solve the problem anyone know of an LPG expert in Kent – I live roughly between Tunbridge Wells and Ashford?

We have done about 8000 miles since and overall I am reasonably happy with the conversion – of course its not as economical as everyone claims (I was expecting that) but I am running a 325i for the price of 320d fuel and a 325i is about 10,000 times nicer to drive than any diesel!

If my car gets fully sorted I would be interested in converting another car but not before smoke testing the vacuum system! Anyone have a smoke tester in Kent?!

Cheers
Robin

It's a bit of a pain to get at but if you remove the intake pipe, the little pipe where it goes onto the IAC just above the throttle body pipe is an absolute favourite.
The hunting and stalling issue is a common problem if you don't get the gas inlets in the right place. You can get the injectors in the right place, you are better to remove the manifold to do it though. The other way to do it is to use straws to dip down to the inlet valves. There is no right or wrong way. As long as it runs right. If the injectors are too far up the inlet tract it will never run properly. If it does have an air leak then the economy will suffer because the fuel trims will be trying to compensate. However if it really did have an air leak the engine management light would be on once it trimmed over about 30 odd percent. I did one a few weeks back. It was trimming at -.8 and 1.6 back to -.8 again on gas. If you can read the fuel trims they can tell you a hell of a lot about what's going on. See what the difference is between petrol and gas.

You're not kidding that was a total pain to remove and it was the one that made a bit of difference - hose looks ok but think it wasnt on tightly.
I am planning on changing following
Dipstick o ring and hose to Oil seperator
Oil seperator (PRV, CCV or whatever everyone calls it) and all 3 related hoses.
Throttle body seal
Air inlet hose (F joint) to fuel pump hose
Sucking jet pump hoses
About £200 worth of bits but my time is free and I will need plenty of it to get to the oil seperator!

When I first bought this car I also bought a BMW auto scanner - it has stacks of different readings I can check but I dont have the specialist knowlege - is it the Adaption, mixture 1 and 2 additive and multiplicative readings I should be checking?

Cheers
Robin

I did a CVV just the other week. I was doing a gas conversion at the time so it was no biggie changing it. But what I have done before and trust me it saves hours.
Remove the throttle body and associated plugs and wires.
Dipstick tube.
Under there you will be able to see a 16mm bolt. Undo that.
Remove all the inlet manifold bolts.
You can leave everything connected and the whole manifold will then lift up giving you good accesss to the bloody thing. I know it's possible to change in situ. If you are a quadruple jointed chimpanzee with the hands of an anorexic ballerina !

Tubbs wrote:If you are a quadruple jointed chimpanzee with the hands of an anorexic ballerina !

you rang?

Hiya John how you doing ?

Nice one! I'll give the manifold trick a try - maybe it will reduce the backache and levels of bad language that might arise when I do the CCV seperator valve...

As for the quadruple jointing - think my joints are that way because they are so knackered.

Cheers
Robin

Hey, I've just seen this thread and my conversion was done by this same company in Hitchin, Feb 2011.

I've got to say I'm pretty happy! The installation is tidy, and has been reliable and has paid for itself and not gone wrong once over more than 15,000 miles. The chap was quite insistant that I go back to him for the 1000 mile service, but I didn't bother, so I'm sure my warentee is voided!

Regarding Robins problem, my idle also hunts for 2 seconds or so when I first switch, but it's not discernable if I am in gear and moving, certainly has never caused a stall. Perhaps it's just a "feature" of the Oscar N system.

Also, forum members will note my other thread about the LPG system not coping at high revs... perhaps due to the Twin Spark engines injector signal... perhaps another limitation of the Oscar N system to be aware of. Oh... and the pressure readings from their sensor don't seem to be correct.

But in summary, for an £800 (inc.) conversion I am chuffed to bits with it. I enjoy playing with engines and seeing as this is my first conversion I don't mind it throwing up a few problems that I can avoid in the future - it's a learning experience for me.

Did they install it properly? YES.
Did they set it up fully and properly? NO.

turtle4288 wrote:Did they set it up fully and properly? NO.

Did you let them finish the job? NO.
It's possible to interpret "you must come back" as meaning "we noticed a quirk and will find a solution for that, which we will apply on your next visit"

But I DID go back for my first service and they didnt offer me a solution to the 'hunting' problem - they brushed it aside with comments of existing vacuum/HT problems - they didnt offer to search the problem for me.
I am afraid that Turtle 4288 is right -
Good Install
Did they set it up properly and fully - NO and mine was a £1500 install not £800!

I am the one trying to sort the hunting out but what would a less enthusiastic owner do? - they would have to pay for someone else to sort it. The best solution for me would be a smoke test of the vacuum system but I dont have access to a tester so I have to laboriously go through the whole system!

In the meantime the car is a pain at junctions, in town etc where it stalls quite easily but on the open road its great!

Cheers
Robin

rossko wrote:

turtle4288 wrote:Did they set it up fully and properly? NO.

Did you let them finish the job? NO.
It's possible to interpret "you must come back" as meaning "we noticed a quirk and will find a solution for that, which we will apply on your next visit"

Yes, I think you're right Ross, I've got nothing against those guys, they did a good job for the money.