Ford Scorpio Forum - Print Page


    
      
        Ford Scorpio Forum
        (https://www.fordscorpio.co.uk/cgi-bin/yabb/YaBB.pl)
      

        General >> Problems >> lpg conversions (questions)
        
(Message started by: scorpio_man on Nov 6^th, 2004, 1:27pm)

Title: lpg conversions (questions)
Post by scorpio_man on Nov 6^th, 2004, 1:27pm

hi there

i'll be at autogas2000 in leeds on thursday morning. if anyone has any questions about converting their car or any issue with their kit, i'll pass it on.

please post your replies before wed (10th nov 2004) evening.

hth
http://www.autogas2000.co.uk/

Title: Re: lpg conversions (questions)
Post by mike.g on Nov 8^th, 2004, 2:11pm

I have a problem with LPG affecting the o2 switching.

It works fine on petrol when I by-pass (short out the LPG wire at the o2 connector block). Plenty of switching.

Normally it doesn't allow the switching signal to reach the ECU when in petrol or LPG. The voltage does change when moving over to LPG but doesn't switch.

Can you ask what might cause this. I'm thinking of changing the 02 emulator but want a second opinion.

Thanks, Mike

Title: Re: lpg conversions (questions)
Post by martin_rowe on Nov 8^th, 2004, 4:18pm

Hi Mike
dead simple, if you have output from the sensor ie voltage is toggling back & forth on the wire from the sensor to the LPG control module the LPG operation is ok if that signal is not duplicated on the wire from the LPG module back to the vehicle ECU then there is a problem with the false signal that the LPG module sends back to the cars ECU.
in other words, the LPG control unit generates a false Llambda signal to fool the cars ECU that all is ok to stop any engine fault codes or check lights.

Title: Re: lpg conversions (questions)
Post by simonmd on Nov 9^th, 2004, 11:01pm

On my 12v, I was pleasantly suprised to find the trip computer still worked when on gas. Question is, HOW?!

I was expecting to see the fuel comp' to show 99.9 MPG when on gas. Surely, as far as the ECU is concerned, the engine is running just on 'fresh air' as the petrol system is shut off.

Title: Re: lpg conversions (questions)
Post by Fitzy on Nov 9^th, 2004, 11:35pm

Hi Simmon

I don't know what gas sysytem you have installed but i believe they all work the same way. On my conversion there are wires which go into the plastic rail above the injectors which holds the electrical supply to all the injectors which comes direct from the EEC-V which opens each injector at the right moment to inject the fuel into the pot, on mine there are eight ( 8 ) wires in total, two for each injector, these wires are then connected in series to each of the injectors wires. Now these don't interfere with the normal running of the car on petrol, but when you switch over to gas these wires with the help of an injector emulator (fitted at the same time) sends fake signals to the cars EEC-V so it still thinks that the injectors are still firing, thus enabling the fuel computer to show fuel consumption as i do believe the Scorpio's fuel computer works off the amount of fuel passing thru the injectors (someone may correct me on this if i'm wrong). My system injects the gas directly into the intake manifold via the throttle housing/air intake.

Some lpg systems use dual fuel injectors to supply either gas or petrol, i think these are called direct injection or sequential multi point, but you should have the wires too which allows your fuel computer to still work.

HTH

Fitzy

Title: Re: lpg conversions (questions)
Post by howiedintheplace on Nov 9^th, 2004, 11:58pm

Hi All
I have not worked on any cars with LPG before so on the learning curve at the moment hence . . .
I picked up a 2.0 L Estate with LPG Saturday, the computer said I had 50 miles of fuel left & it was slowly going down even though I was running on gas, most confusing. Is this normal, says I have 10 miles left now.
I am going to take a can of petrol (to be on the safe side) & run it out of fuel (so the computer gizmo thinks) just to see what happens. I think Fitzy may have almost answered this question with the previous post as it sounds like it calculates fuel left based on flow, but I thought it calculated it on the actual fuel level in the tank? The gas tank is full by the way.

Title: Re: lpg conversions (questions)
Post by scorpio_man on Nov 10^th, 2004, 8:13am

hi there

i though it was worked out on manifold vacuum? that's another question to ask. :)

i'll print out a list of questions at about 10pm tonight (4am start tomorrow).

regards

Title: Re: lpg conversions (questions)
Post by Fitzy on Nov 10^th, 2004, 11:05am

Hi Dave

Mine does the same when i'm running on gas, the miles tilll empty goes down but the needle doesn't move still reads 3/4 full, i do believe that the miles to go is worked out using the speed of the car (i might be wrong here) at various intervals through out the journey, but mine doesn't go down that much as i always have at least half a tank of petrol at all times incase i can't refill with gas, but after i stop the car and then restart it later the miles till empty goes back up to a reasonable figure, if yours only had enough for 50 miles when you picked it up then the movement of the car with this small amount of fuel would give various readings i think. Try putting more petrol in upto at least half a tank and see how it goes from there, if it still goes down drastically have it checked out you might be using gas and petrol at the same time!!!!!!!

Scorpio-man, you might be right about the vaccum part as i said i wasn't sure on how the fuel used was calculated, maybe Eric or save the night will know.

Will keep a close eye on mine to check this out. When you go to the lpg fair could you keep an eye on your petrol readings and check on your trip computer if the miles till empty goes down or not.

Regards,

Fitzy ;) ;D ;)

Title: Re: lpg conversions (questions)
Post by Danny_R on Nov 10^th, 2004, 9:36pm

Andrew, you still gonna be in Leeds round about 1:30ish? we could meet up :)

Regards

Danny R

Title: Re: lpg conversions (questions)
Post by scorpio_man on Nov 11^th, 2004, 6:23pm

sorry danny. :(

never saw your post until just now. i was at autogas2000 'till 1pm as well! :-[ story to follow at some point! :o

looks like it'll need to be next time you're back 'home'.

Title: Re: lpg conversions (questions)
Post by Danny_R on Nov 12^th, 2004, 3:51pm

Hi Andrew, no worries mate. Hope you got everything sorted out ok.

Take care

Danny R

Title: Re: lpg conversions (questions)
Post by scorpio_man on Nov 19^th, 2004, 7:03pm

hi there

i've sent a new page to eric r for the main site.

http://www.anyboard.net/autos/cars/scorpio/posts/315.html

hth
ps. i'll post some q & a that i asked later.