LPG Installation Help
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- Brianmoooore
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The other red/white goes straight to the fuel pump relay in a short loop.
If the vapouriser has a connection at the top, that's where the air's going to vent from. Make sure this pipe doesn't have a hump in it on its way to tee into the heater hose, that would trap the air.
If the vapouriser has a connection at the top, that's where the air's going to vent from. Make sure this pipe doesn't have a hump in it on its way to tee into the heater hose, that would trap the air.
Right, been ringing around for lgp mixer plates and have found one company that can do it for £44 inc delivery. One company said that they dont recomend using the mixer as they produce backfires and the backfire cat flaps dont work that well and bend and break the afm. One company said that if the mixer is between the airbox and airflow meter, the gas wont be injected correctly and he said I should hold the flap of the afm open with a grub screw and use a mixer after the airflow meter. this would mean starting on lpg all the time. He also mentioned that I would soon need to get upgraded HT leads as the standard ones will late create misfires. I am unsure what to do now?
What you think to what they have said?
Cheers
What you think to what they have said?
Cheers
Backfires happen but the catflaps do work and protect the AFM, mine has survived 3 now with no ill effects
Ive never heard the thing about plug leads though, i just changed the plugs for NGK's and now ive finished *tinkering it's fine.
Mr Moooore has been running on gas for years so he will know if theres any problems in that area.
* tinkering reads better as 'Pratting about with it'
Ive never heard the thing about plug leads though, i just changed the plugs for NGK's and now ive finished *tinkering it's fine.
Mr Moooore has been running on gas for years so he will know if theres any problems in that area.
* tinkering reads better as 'Pratting about with it'
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StuBeeDoo
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Sounds like you're getting similar crap to what I got when I was researching for my install.jon_d_h wrote:What you think to what they have said?
It amazes me that so-called Professional Installers/Suppliers can talk such utter shit!
When I was getting quotes to have the system fitted (before Brian convinced me to DIY it), one LPGA-recommended installer told me that fitting LPG to a car over 10 years old is illegal!
One told me that he was not certified to do a safety check on the old mixer type systems but for £150 he would set it up for me and have a look, no certificate though
Thats both a load of bull and totally useless as the leonardo is a self-learning system
Thats both a load of bull and totally useless as the leonardo is a self-learning system
- Brianmoooore
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What a total load of bo**ocks!! The LPG industry seems to attract the same kid of person as those that sell double glazing, green energy schemes, and the like. Confuse the customer with pseudo science, and sell them things they don't need at inflated prices!jon_d_h wrote:Right, been ringing around for lgp mixer plates and have found one company that can do it for £44 inc delivery. One company said that they dont recomend using the mixer as they produce backfires and the backfire cat flaps dont work that well and bend and break the afm. One company said that if the mixer is between the airbox and airflow meter, the gas wont be injected correctly and he said I should hold the flap of the afm open with a grub screw and use a mixer after the airflow meter. this would mean starting on lpg all the time. He also mentioned that I would soon need to get upgraded HT leads as the standard ones will late create misfires. I am unsure what to do now?![]()
What you think to what they have said?
I have run a M20B25 on LPG for approximately 100,000 miles, from just before 200,000 miles to just before 300,000.
In this time I have had three backfires - two which were my fault, caused by me doing something I shouldn't, and one which happened to my wife, where I know she changed into fifth gear when she wanted third, then tried to correct her mistake..
The disc on the backfire flap has taken on a slightly convex shape, but otherwise has done its job and works as well as it ever did.
The HT leads on the car are the ones it left the factory with in 1988, and are as good as new.
These LPG installers are used to dealing with things like Land Rovers, which need a new set of leads every couple of years on LPG. They just don't understand the quality of the E30!
Just get on and convert the thing - every day you run on petrol is wasting money!
On the often mentioned subject of insuring a LPG converted car, I insured one last night on the 'net. and on the 'phone this morning. Using 'go compare' and 'confused', which both led me to the Post Office, but £2 cheaper with the former.
Both the go compare and confused websites let you enter LPG under conversions, and there has been no mention of certificates on the 'net or on the 'phone.
Good pointJust get on and convert the thing - every day you run on petrol is wasting money!
And thanks for the info. I think they all are just after more money and want me to change to the multipoint system.
1 last question about the mixer
Cheers
- Brianmoooore
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All I know about the 33mm venturi that I have is that I took it off a 325 E30. I never saw the car working on LPG, and neither did the owner of the car at that time! The venturi on my own red 325 was put there ten years ago, and I've long since forgotten what bore it has.
Are they willing to change the venturi at a later date (for a small fee)? I'd be tempted to try the 36mm and see what happens.
Are they willing to change the venturi at a later date (for a small fee)? I'd be tempted to try the 36mm and see what happens.
ok. I didnt ask about changing it after trying it. He told me that the OMVL 90 will work for up to 50mm and is adjusted for different sizes. Il get one ordered tomorrow.
Cheers
I guess the thicker cable goes to the fuel pumpThe other red/white goes straight to the fuel pump relay in a short loop.
Cheers
- Brianmoooore
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Don't quote me, but I think it's the thinner one that goes to the pump relay.jon_d_h wrote:I guess the thicker cable goes to the fuel pump
You can see the other end at the pump relay, about two inches away, so it should be easy to tell!
Ok
The mixer has been ordered from FES lpg. So hopefully will be here by the weekend. All the wiring is done but the lambda and the 2 yellows which I am stuck with. I would have thought that the 2 yellows would be closed circuit when the leonardo is on but the switch is in the petrol position. This way, the car should run as normal and the feed to the injectors will go frm the DME relay, through the closed contact in the leonardo and then to the injectors. But when I check, there is a very high resistance between the 2 yellows (4 meg). Is there something wrong?
Cheers
The mixer has been ordered from FES lpg. So hopefully will be here by the weekend. All the wiring is done but the lambda and the 2 yellows which I am stuck with. I would have thought that the 2 yellows would be closed circuit when the leonardo is on but the switch is in the petrol position. This way, the car should run as normal and the feed to the injectors will go frm the DME relay, through the closed contact in the leonardo and then to the injectors. But when I check, there is a very high resistance between the 2 yellows (4 meg). Is there something wrong?
Cheers
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StuBeeDoo
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On mine, I identified the three different colours that go to the injectors, opened the loom near the plug, cut the cable that goes to all 6 injectors and connected one yellow to either end of the cut cable.
You're right, the yellows open-circuit the injectors when the gas is switched on.
You're nearly there.........
You're right, the yellows open-circuit the injectors when the gas is switched on.
You're nearly there.........
Thats what I thought but when the leonardo is set in the run on petrol mode on the switch, it is open circuit when I would of thought it would be closed in this position and open when I set it to run on gas.StuBeeDoo wrote:On mine, I identified the three different colours that go to the injectors, opened the loom near the plug, cut the cable that goes to all 6 injectors and connected one yellow to either end of the cut cable.
You're right, the yellows open-circuit the injectors when the gas is switched on.
You're nearly there.........
Cheers
spotted this on the bay a while ago, if you have issues with the one you have ordered, and no, I am not the seller!
http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0280267529
The yellow wires should in theroy be joined when the leonardo is powered down, pop the case and check the relay in there! It does have a software config for using the yellows for a memory reset, which may affect it, best pet is to wire it to 12v with the perm and ign live and ground, then check the yellows again while flicking from petrol and to gas...
best of luck
http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0280267529
The yellow wires should in theroy be joined when the leonardo is powered down, pop the case and check the relay in there! It does have a software config for using the yellows for a memory reset, which may affect it, best pet is to wire it to 12v with the perm and ign live and ground, then check the yellows again while flicking from petrol and to gas...
best of luck
- Brianmoooore
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http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0280267529
ANYONE ON HERE LIKELY TO BID ON THIS, because at the sort of price it's at now, I will!
If anyone here wants it, post here, or PM me, in the next hour, and I won't bid.
ANYONE ON HERE LIKELY TO BID ON THIS, because at the sort of price it's at now, I will!
If anyone here wants it, post here, or PM me, in the next hour, and I won't bid.
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StuBeeDoo
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When you checked the circuit, did you allow for the fuel overlap phase?jon_d_h wrote:Thats what I thought but when the leonardo is set in the run on petrol mode on the switch, it is open circuit when I would of thought it would be closed in this position and open when I set it to run on gas.
I will first see how it is set up when I get it up on the laptop. If it looks to be set up I will then check the relay.The yellow wires should in theroy be joined when the leonardo is powered down, pop the case and check the relay in there! It does have a software config for using the yellows for a memory reset, which may affect it, best pet is to wire it to 12v with the perm and ign live and ground, then check the yellows again while flicking from petrol and to gas...
Good buy! I wouldnt have seen that on ebay because I was searching for "lpg mixer". I have got mine fitted inside the air box now.http://cgi.ebay.co.uk/ws/eBayISAPI.dll? ... 0280267529
ANYONE ON HERE LIKELY TO BID ON THIS, because at the sort of price it's at now, I will!
If anyone here wants it, post here, or PM me, in the next hour, and I won't bid.
How long is that?When you checked the circuit, did you allow for the fuel overlap phase?
Also Brian, you sent me a diagram of the interface lead plug that i have got to plug into the leonardo. It says "looking into the plug so does that mean looking at the pins?
Cheers
this may help with the cable:
http://www.spacevista.afreeweb.info/cable/
fuel overlap phase is normally ~ 2 - 4 seconds
it should still join the two yellows if the switch is in petrol mode.
http://www.spacevista.afreeweb.info/cable/
fuel overlap phase is normally ~ 2 - 4 seconds
it should still join the two yellows if the switch is in petrol mode.
- Brianmoooore
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The interface plug connections that I sent you are looking into the front of the plug that connects to the interface box, with the wires coming out of the rear.
Ok cheers
Got that soldered now. Got a couple more questions.
Is the I/D of the pipe for the heater where I need to tee into 19mm? So I wil two 2 x 19mm by 1 x 15mm tee? Where from?
Also, how can I get a 90 degree bend out of the mixer pipe. I noticed on your photos Brian, that you have a 90 degree copper bend coming out of the mixer. Did you cut the gold pipe back? And how did you attach the copper bend to the golden mixer pipe?
Cheers
Got that soldered now. Got a couple more questions.
Is the I/D of the pipe for the heater where I need to tee into 19mm? So I wil two 2 x 19mm by 1 x 15mm tee? Where from?
Also, how can I get a 90 degree bend out of the mixer pipe. I noticed on your photos Brian, that you have a 90 degree copper bend coming out of the mixer. Did you cut the gold pipe back? And how did you attach the copper bend to the golden mixer pipe?
Cheers
- Brianmoooore
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E30 heater pipe is 16mm bore, AFAIK, and you will need 16mm equal tees.
Try to get metal ones rather than plastic, as these have been known to fail.
The 90 degree bend I have on my mixer is a 'Yorkshire' 15mm plumbing elbow, and, IIRC, is soldered to the brass mixer pipe.
Try to get metal ones rather than plastic, as these have been known to fail.
The 90 degree bend I have on my mixer is a 'Yorkshire' 15mm plumbing elbow, and, IIRC, is soldered to the brass mixer pipe.
- Brianmoooore
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Fourth item from the bottom is what you want: http://www.tinleytech.co.uk/acatalog/Pipes_and.html
As Far As I Know. If I Recall Correctly.
As Far As I Know. If I Recall Correctly.
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gareth
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my heater hoses are a mish-mash of E30 and E32 parts so may well not be the same size as yours, i can't remember exactly what bits are from what car, i just made them fit with what i had! i can tell you that my tee pieces are made of 15mm copper yorkshire plumbing fittings though! 1x tee piece, 3x short lengths of 15mm copper pipe and 3x end to end connector pieces, all soldered together. they were a little loose but have proved ok.jon_d_h wrote:Definatly 16mm? I have some 15mm tee pieces and they are very loose in the heater pipe? I saw on Garaths thread that he was ordering 19mm ones.
Sole founder of Fe2O3-12V it's a lifestyle

LSD rebuilding / modification services provided, PM for details

LSD rebuilding / modification services provided, PM for details
Cheers
I got the tee pieces today and fitted them. There is a very small leak from somewhere now so I will get that sorted tomorrow before I drive it. All I have left to do is:
1) Wire in the 2 yellow wires when I set up the leonardo on the laptop (I have a feeling that I could have a split in the cable somewhere or the relay is dodgy!)
2) Fit the lambda and boss. I have got the boss and a 4 wire lambda now.
3) Fit the pipe between the stepper motor and the mixer.
4) Fit the filler (This can be last as I have a full tank of gas)
Where is the best place to fit the lambda boss? Can It be welded on with the pipe still on the car?
Hopefully be running on gas by the weekend!
Cheers
I got the tee pieces today and fitted them. There is a very small leak from somewhere now so I will get that sorted tomorrow before I drive it. All I have left to do is:
1) Wire in the 2 yellow wires when I set up the leonardo on the laptop (I have a feeling that I could have a split in the cable somewhere or the relay is dodgy!)
2) Fit the lambda and boss. I have got the boss and a 4 wire lambda now.
3) Fit the pipe between the stepper motor and the mixer.
4) Fit the filler (This can be last as I have a full tank of gas)
Where is the best place to fit the lambda boss? Can It be welded on with the pipe still on the car?
Hopefully be running on gas by the weekend!
Cheers
- Brianmoooore
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Ideally the lambda should be fitted to monitor the exhaust from all the cylinders, but in practice, the gasses from three will do. I fit them on the pipe nearest the centre of the car, on the semi vertical bit, just above the bends where they turn horizontal. There's a nice little space there where the lambda can fit, clear of everything and out of harms way.
To make a half decent job of welding the boss on, the downpipes will need to come off.
To make a half decent job of welding the boss on, the downpipes will need to come off.
Ok cheers. Il do that on the weekend. As you said earlier on in the thread that only one of the wires (purple) from the leonardo is used to go to the lambda. I have a 4 wire lambda, how is it wired up?
Cheers
Cheers
- Brianmoooore
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Two white wires are the heater - one to earth and the other to ignition switched live.
Grey is signal earth - wire to Leonardo earthing point. Black is the lambda signal to the Leonardo.
Grey is signal earth - wire to Leonardo earthing point. Black is the lambda signal to the Leonardo.
Incidently, I wires my lambdas heater via a relay to perminant live, the relay triggered with the blue wire from the leonardo, too much of a tidy mind to have the lambda burning away for no reason on petrol...
Also, does anyone know if there is a benefit in wiring the lambdas signal to the motronic ECU, I know it has a pin for one... what happens?
Also, does anyone know if there is a benefit in wiring the lambdas signal to the motronic ECU, I know it has a pin for one... what happens?
- Brianmoooore
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Now you mention it, that's how mine is wired, and what I should have written!! Not that you'll be driving very far on petrol, of course!johnlouis wrote:Incidently, I wires my lambdas heater via a relay to perminant live, the relay triggered with the blue wire from the leonardo,
Connecting up the lambda to the ECU won't do anything at all when running on LPG, and I think I've heard it improves MPG slightly on petrol, at a slight expense of power.
Right, Been doing the interface lead for my laptop, I wired up the interface connector as the diagram showed looking into the plug at the pins.
1= Rx
2= earth
3= 12v
4= Tx
I have wired 3 of these up and left the 12v with nothing wired onto it. Should this be wired up at all because when I have tried going on the AEB leonardo software, it comes up with "link not possiable, check connection". Has anyone got any idea why? I am using a new laptop with a usb serial convertor (set to COMS port 5) which I know can somtimes be tricky.
Cheers
1= Rx
2= earth
3= 12v
4= Tx
I have wired 3 of these up and left the 12v with nothing wired onto it. Should this be wired up at all because when I have tried going on the AEB leonardo software, it comes up with "link not possiable, check connection". Has anyone got any idea why? I am using a new laptop with a usb serial convertor (set to COMS port 5) which I know can somtimes be tricky.
Cheers
- Brianmoooore
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The power for the level shifter comes from the Leonardo, so the 12v pin has to be connected. It can't possibly work without it.
I have made the circuit below, I have now wired in the 12v which i forgot first time!Brianmoooore wrote:The power for the level shifter comes from the Leonardo, so the 12v pin has to be connected. It can't possibly work without it.
When should I have 12v at the 12v pin of the leonardo?
Cheers



