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LPG wiring
Posted: Fri Jul 10, 2009 3:58 pm
by Brenner5
I need help putting the Leonardo ecu wiring in my car, I have searched the forum and found it very useful but need some help/tips on where to get the wiring from.
I’ve already got the documents showing the wires etc from the zone
Leonardo brown ”“ negative coil or black wire from pin 9 C101 ”“ where is the C101 (white box under glovebox? Or ecu pin 74
Leonardo blue/yellow ”“ brown/blue from TPS ”“ under TPS I guess
Leonardo blue ”“ alternative fuel electrovalves x 3 ”“ where are these exactly?
The oxygen sensor will be connected through the BMW supplied wiring;
Leonardo grey ”“ ?
Leonardo purple ”“ black wire from?
Leonardo yellow x2 ”“ red/white injector wires ”“ do I connect both yellow wires to the red/white wires?
Leonardo red (fused) ”“ green/yellow from?
Leonardo red/black (fused) ”“ positive battery from anywhere I guess?
Leonardo black ”“ ground from anywhere
Leonardo orange ”“ red/brown from the temp sensor
Leonardo Green and white wire connect to the fuel level sensor ”“ mine is blue and brown.
Where can I get a connection for my VDO gauges so they only light up when the car lights are switched on?
VDO gauge is in the centre console at the bottom
Connection of heater pipes to vaporiser;
Anyone go any pics of this?
Re: LPG wiring
Posted: Fri Jul 10, 2009 6:06 pm
by e301988325i
Try this thread I started a while back, some pics in there too
http://www.e30zone.net/modules.php?name ... highlight=
Re: LPG wiring
Posted: Fri Jul 10, 2009 6:15 pm
by e301988325i
Brenner5 wrote:I need help putting the Leonardo ecu wiring in my car, I have searched the forum and found it very useful but need some help/tips on where to get the wiring from.
I’ve already got the documents showing the wires etc from the zone
Leonardo brown ”“ negative coil or black wire from pin 9 C101 ”“ where is the C101 (white box under glovebox? Or ecu pin 74
I've got wires on coil positive and negative.
Leonardo blue/yellow ”“ brown/blue from TPS ”“ under TPS I guess
I cut into the ECU wiring harness near the ECU. protected from the elements and heat.
Leonardo blue ”“ alternative fuel electrovalves x 3 ”“ where are these exactly?
These are the propane/lpg valves, one on the tank, one in the engine bay and one on the vapourisor.
The oxygen sensor will be connected through the BMW supplied wiring;
Leonardo grey ”“ ?
unattached
Leonardo purple ”“ black wire from?
I cut into the ECU wiring harness near the ECU. protected from the elements and heat. (large black wire)
Leonardo yellow x2 ”“ red/white injector wires ”“ do I connect both yellow wires to the red/white wires?
Split red/white attach yellow/yellow each end, picture in the link above of where I did it.
Leonardo red (fused) ”“ green/yellow from?
Coil
Leonardo red/black (fused) ”“ positive battery from anywhere I guess?
from positive around battery tray area
Leonardo black ”“ ground from anywhere
Leonardo orange ”“ red/brown from the temp sensor
Leonardo Green and white wire connect to the fuel level sensor ”“ mine is blue and brown.
Where can I get a connection for my VDO gauges so they only light up when the car lights are switched on?
VDO gauge is in the centre console at the bottom
heater control lights??
Connection of heater pipes to vaporiser;
Anyone go any pics of this?
Pics in thread above, not fun to do, requires draining of coolant and carefull re-filling. Soapy water to aid fitting tight hoses much reccomended.
Re: LPG wiring
Posted: Sat Jul 11, 2009 1:12 pm
by Brenner5
Thanks!!
Gona have a crack at this today!!
Re: LPG wiring
Posted: Sat Jul 11, 2009 1:27 pm
by e301988325i
Cut the injector wire last!!! as this really does disable the car completely until the leonardo is running!
Re: LPG wiring
Posted: Tue Jul 14, 2009 1:56 pm
by Brenner5
Car is off road at the mo!1
Thanks for the tip anyway
e301988325i wrote:Brenner5 wrote:
Leonardo blue ”“ alternative fuel electrovalves x 3 ”“ where are these exactly?
These are the propane/lpg valves, one on the tank, one in the engine bay and one on the vapourisor.
[/b]
Right...
Need to connect the valves; one wire from the valve goes back into the Leonardo blue wire and is the other wire on the valve a positive?
Heater pipes, my vaporiser has an 'in' and 'out' for water
The heater pipes on the car which one is in and out?
The one on top or below?
Also, my vaporiser has one valve connected to it where the lpg feed comes from the tank and it goes directly into the vaporiser
Should I set this up separately as that’s what I have seen in some installations, it is usually situated near the top near the fuse box.
I can’t show you pics of what I mean as they are blocked at work!!
Re: LPG wiring
Posted: Wed Jul 15, 2009 2:14 pm
by Brenner5
Anyone?
Re: LPG wiring
Posted: Wed Jul 15, 2009 2:46 pm
by Brianmoooore
Brenner5 wrote:
Right...
Need to connect the valves; one wire from the valve goes back into the Leonardo blue wire and is the other wire on the valve a positive?
Blue wire goes to one side of each solenoid valve. Most systems have three.
Other side of solenoid valves goes to earth. Note that most solenoids can be connected either way around, bur a few have suppression diodes built in, and must be connected + to positive, or blue.
Heater pipes, my vaporizer has an 'in' and 'out' for water
The heater pipes on the car which one is in and out?
The one on top or below?
Heater flow is from bottom to top, so 'in' connects to the bottom stub pipe, and 'out' connects to the 'tee' hose.
Also, my vapouriser has one valve connected to it where the lpg feed comes from the tank and it goes directly into the vapouriser
Should I set this up separately as that’s what I have seen in some installations, it is usually situated near the top near the fuse box.
I can’t show you pics of what I mean as they are blocked at work!!
I think I know what you mean - the filter solenoid is screwed directly into the vapouriser. Not a problem, as long as you can get at the filter bowl for servicing.
Re: LPG wiring
Posted: Wed Jul 15, 2009 6:58 pm
by Brenner5
Brian,
to make this clear..
vaporiser-in connects to the bottom pipe in the car
Vaporiser-out connects to the top pipe in the car
so 2 pipes in the car get cut and tee peices inserted into both..
Re: LPG wiring
Posted: Wed Jul 15, 2009 9:08 pm
by e301988325i
Water flows out of the head into the matrix. . . If that helps, can go and check if needed
Re: LPG wiring
Posted: Wed Jul 15, 2009 11:13 pm
by Brianmoooore
Brenner5 wrote:Brian,
to make this clear..
vaporiser-in connects to the bottom pipe in the car
Vaporiser-out connects to the top pipe in the car
so 2 pipes in the car get cut and tee peices inserted into both..
Yes, assuming the heater pipes are on the right way around.
Alternitavely, if you disable the electric heater valve by removing its fuse, you can connect your vapouriser in series with the top heater pipe. This will give better heater performance in winter, but you won't be able to turn the heat fully off in summer.
Re: LPG wiring
Posted: Thu Jul 16, 2009 12:15 am
by CHR1S1990
tip for heater pipes - i did not "T" into the original water pipes, i simply used the two in and out pipes which heat the throttle body (took about 10 minutes with a little persuasion as they are a slightly smaller diameter than you would like). I was going to do this anyway to try and get a little more power out of the engine and mine starts from gas every time without having to warm up on petrol
chris
Re: LPG wiring
Posted: Sat Aug 29, 2009 8:48 pm
by Brenner5
e301988325i wrote:Brenner5 wrote:
Leonardo yellow x2 ”“ red/white injector wires ”“ do I connect both yellow wires to the red/white wires?
Split red/white attach yellow/yellow each end, picture in the link above of where I did it.
When i split the red/white wire; do i still need to rejoin it?
So when i connect the leonardo yellow wires to each ends of the red/white wire, should the red/white wire still connect to each other?
Can i fill up my lpg tank without all the wiring connected?
I'm thinking of putting some lpg in so i can test it once all the wiring is connected
Re: LPG wiring
Posted: Sat Aug 29, 2009 11:44 pm
by e301988325i
each end of the red white to a yellow and thats it. DO NOT rejoin red white together. fill up is the last thing to do in my opinion.
Re: LPG wiring
Posted: Tue Sep 01, 2009 5:34 pm
by Brenner5
Thanks for your help guys...
All done BUT when it came to bleeding the radiator i discovered a water leak!!
Vaporiser is leaking from one of the water pipes, need to source a rubber seal now

Re: LPG wiring
Posted: Tue Sep 08, 2009 9:45 pm
by Brenner5
Update:
Got vaporiser sorted, connected pipes and the rest of the wiring.
Filled up the tank once i figured out how to fill it up!!)
2 problems:
I can smell gas inside the car, seems like it is coming from the heaters? not sure but i will check this properly
When i switch over to gas there is an amber that light that keep flashing.
Soon as change over occurs the car turns off.
I have connected a laptop to the lpg ecu and will make some changes soon, no errors pop up though.
some screen shots below (note that the settings are different as i was messing around)

Re: LPG wiring
Posted: Tue Sep 08, 2009 10:00 pm
by Brianmoooore
Brenner5 wrote:Soon as change over occurs the car turns off.
Explain further! Do you mean it doesn't run on gas; just stops?
Re: LPG wiring
Posted: Tue Sep 08, 2009 10:06 pm
by e301988325i
Brenner5 wrote:
When i switch over to gas there is an amber that light that keep flashing.
Soon as change over occurs the car turns off.
I think that gas leak needs sorting first of all, but. . .
The flashing amber light signifies that the car is ready to switch over to gas, when it is solid amber you're on the cheap stuff!
Mine system is set to changeover on 'deceleration' not'accelaration' like yours. My fuel overlap is set to 0secs.
Here's how I switch over, with the car in third I get the car to 2500rpm (30ish), flick the switch over, then lift off the throttle completely until the amber light goes solid, then drive as normal on gas

Re: LPG wiring
Posted: Tue Sep 08, 2009 10:42 pm
by Brianmoooore
There might not be a gas leak as such. The additive which is included with the LPG is very strong, and the slightest trace of unburnt gas around is easily detected.
It could be gas drifting out of the air box.
Having changeover set to happen on acceleration is the road to a massive backfire!
Re: LPG wiring
Posted: Wed Sep 09, 2009 12:30 am
by Brenner5
Start car on petrol, when i switch over to lpg (turn switch to lpg), amber light constantly flashes on the lpg switch, car is still driveable however when i rev over 2000 rpm i can hear the lpg ecu tick over and then the car will lose power. It goes into the ignition position where all the lights are on my dash.
The car has not ran on gas so far.
My airbox does have holes in the bottom and the mixer is placed at the other end of the airbox (front of the car not near the afm side) would this make a difference?
There is a small valve that can be turned (swivel) on the multivalve on the tank, what is that for?
Re: LPG wiring
Posted: Wed Sep 09, 2009 12:47 am
by Brianmoooore
Mixer needs to be fixed tight against the AFM, or as close to the throttle body as possible (bearing in mind that it also needs to be before the air tube branch to the idle valve), if you have an AFM flap opening device.
Multivalve will have a manual shut off valve on the inlet side, and possibly one on the outlet as well.
Re: LPG wiring
Posted: Wed Sep 09, 2009 11:06 am
by Brenner5
I will move the mixer so it will be closer to the afm tonight
Would the mixer being placed further away from the afm stop the car running on gas?
Re: LPG wiring
Posted: Wed Sep 09, 2009 7:23 pm
by gareth
re the gas smell, the exhaust while on LPG will smell different so check it's not that.
moving the mixer further away shouldn't stop it running on gas. before you get the hang of it and get it set up, switching can be tricky. my first problem when i installed mine was forgetting to open up the manual shut-off valve on the tank

Re: LPG wiring
Posted: Wed Sep 09, 2009 9:22 pm
by e301988325i
Brenner5 wrote:Start car on petrol, when i switch over to lpg (turn switch to lpg), amber light constantly flashes on the lpg switch, car is still driveable however when i rev over 2000 rpm i can hear the lpg ecu tick over and then the car will lose power. It goes into the ignition position where all the lights are on my dash.
Have you tried switching over as I described above? It can take a couple of seconds, you need to be moving in gear to keep the engine turning over whilst the changeover happens, revving at a standstill is unlikely to work unless the car is well setup, which is unlikely striaght out of the box.
Alex
Re: LPG wiring
Posted: Wed Sep 09, 2009 9:49 pm
by stonesie
"My airbox does have holes in the bottom and the mixer is placed at the other end of the airbox (front of the car not near the afm side) would this make a difference? "
Yes, a massive one, those holes are letting air in that has not been through the mixer = a very lean mix.
When LPG runs lean it backfires
I got caught out by that manual shut-off too

Re: LPG wiring
Posted: Wed Sep 09, 2009 9:54 pm
by Brianmoooore
gareth wrote:moving the mixer further away shouldn't stop it running on gas.
Moving it further away won't affect it, but moving it before the holes in the airbox will!
Re: LPG wiring
Posted: Thu Sep 10, 2009 12:27 am
by Brenner5
e301988325i wrote:
Have you tried switching over as I described above? It can take a couple of seconds, you need to be moving in gear to keep the engine turning over whilst the changeover happens, revving at a standstill is unlikely to work unless the car is well setup, which is unlikely striaght out of the box.
Alex
I'll try this on Saturday and will post the outcome on here..
Just another point to mention;
When the car is on and i turn it over to lpg, the car turns off and i can hear the tank (multivalve) producing a noise (whooshing) for a few seconds - is that normal?
Re: LPG wiring
Posted: Thu Sep 10, 2009 1:12 am
by gareth
Brianmoooore wrote:gareth wrote:moving the mixer further away shouldn't stop it running on gas.
Moving it further away won't affect it, but moving it before the holes in the airbox will!
i'd missed the holes in the airbox

Re: LPG wiring
Posted: Thu Sep 10, 2009 1:15 am
by gareth
Brenner5 wrote:When the car is on and i turn it over to lpg, the car turns off and i can hear the tank (multivalve) producing a noise (whooshing) for a few seconds - is that normal?
it sounds like there could be a restriction, depressurising on the engine side as the forward solenoid valves open.
I'd check that shutoff valve and the operation of all solenoids. if you're using second hand parts they may be clogged. i've had the solenoids got totally clogged with black metallic crap from the gas, stopping them opening properly and causing fuel starvation
oh and that whooshing isn't a leak is it?

Re: LPG wiring
Posted: Tue Oct 06, 2009 12:06 am
by Brenner5
Car is partially running on lpg now, think i'll have to look into what Gareth has said above about clogged up solenoids.
car runs in 1st/2nd gear but quite hesitant, loses power in 3rd altogether.
the tank is making a ticking sound, not loud but not sure why this is?
Re: LPG wiring
Posted: Tue Oct 06, 2009 12:26 am
by Brianmoooore
Do you have a decent earth on the appropriate side of the tank solenoid?
Re: LPG wiring
Posted: Tue Oct 06, 2009 8:04 pm
by Brenner5
Earth is fine, i used another earth and it didn't make a diffrrence.
I have got tried to tune the vaporised to help the car idle better, used a manual stepper and got the idle right.
However once putting on the Leonardo stepper, the car is not as smooth, I have hooked up a laptop, just need to get the settitngs right.
The car can switch over to lpg fine now but previously i could drive the car on lpg, now it is very hesitant and turns off!
Re: LPG wiring
Posted: Tue Oct 06, 2009 8:34 pm
by gareth
here's a setup guide that should help you. i managed to get my vap tuned to the point the stepper only floated within ±3 steps from the default value. incidentally, with my M30 and OMVL R90/E vap, the idle bleed is totally closed
http://www.diy-lpg.co.uk/articles/files ... -loop.html
Re: LPG wiring
Posted: Tue Oct 06, 2009 8:50 pm
by Brianmoooore
Leonardo software set for the wrong type of lambda sensor?
What's the stepper display doing on the laptop?
Re: LPG wiring
Posted: Thu Oct 08, 2009 5:30 pm
by Brenner5
car is driveable on lpg now!!
I've been using the link Gareth provided.
Brian; i think the 02 sensor setting is right (0-1v)
i need to adjust the stepper a bit as it does get a bit jerky, especially on cold.
temp is below half when driving
feels down on power at the moment
should the car be a bit rough on cold startup on lpg?
will try and get the stepper settings right over the weekend.
what should the idle be set to on lpg?
does anyone have any rough figures for the stepper?
is there something i can run through the lpg system to clearout any dirt?