Cant start car on lpg all of a sudden!!!

[lars04]

I've parked the car up as I replaced the suspension and now it won't start on gas (petrol pump not working) all of a sudden can someone help me with this please? I have a 1993 discovery with the 3.5 if that helps.

[Baggy]

Lars04 ....do you have the switch that has the four (green) lights with the button that you can swap over between LPG and petrol?

If you turn on the ignition on there's one single light (on the LPG switch) that is flashing amber above the lights (in green) indicating the level of LPG in the tank?

If you press and hold down the button that normally switches between LPG and petrol until the amber light stops blinking the engine should start on LPG only.

When its blinking it will start only on pertrol and then switch over to LPG after a few sconds.

My (electric fuel pump) is working intermittantly and Im running her on LPG only.

Hope that assists,

Cheers

Baggy

[lars04]

Lars04 ....do you have the switch that has the four (green) lights with the button that you can swap over between LPG and petrol?

If you turn on the ignition on there's one single light (on the LPG switch) that is flashing amber above the lights (in green) indicating the level of LPG in the tank?

If you press and hold down the button that normally switches between LPG and petrol until the amber light stops blinking the engine should start on LPG only.

When its blinking it will start only on pertrol and then switch over to LPG after a few sconds.

My (electric fuel pump) is working intermittantly and Im running her on LPG only.

Hope that assists,

Cheers

Baggy

Gday mate, Yea I've got that switch , and yes I do hold the button down my fuel pump isn't working either well the whole take is out of the car now I've been running only gas since I got it. I took the tank out then moved it (gas running fine) parked it to change the springs now nothing! I'm going to install an aftermarket external fuel pump and ditch this gas system one I'm not a fan of gas and also it takes up to much boot space.
Thanks for your help.
Cheers
Lars

[Baggy]

Hi Lars

Bugger ......Hoping that bee utey picks up your thread.

He's a full bottle on all things LPG .....I believe that's his trade and if he doesn't maybe send him a private message.

He's one of the most helpful members and his advice has been invaluable to many on this site.

Hope you get it sorted shortly .....

Cheers

Baggy

[lars04]

Hi Lars

Bugger ......Hoping that bee utey picks up your thread.

He's a full bottle on all things LPG .....I believe that's his trade and if he doesn't maybe send him a private message.

He's one of the most helpful members and his advice has been invaluable to many on this site.

Hope you get it sorted shortly .....

Cheers

Baggy

Gday mate Yea he's commented on another post I did on the gas in a different section, checked all my fuses as he told me to do and there all fine I'm stumped :(

[bee utey]

Diagnosis thrives on details. "Gas don't go, haaalp!!!" is summarily lacking in detail, makes it hard to be useful. Pictures, closeups of switches, valves, fuses etc may help. Have you looked at the back of the switch yet? Probed the terminals with a test light and see what comes on when?

[bee utey]

And today I got one just the same, "Gas don't go, haaalp!!!" on an old Hilux, fortunately his petrol system was still working just well enough to get to me. Turned out that the line fuse for the LPG was somewhere under the bonnet, and the holder's lid had fallen off. The fuse had got wet and corroded slightly and there was a tiny bulge in the plastic body of the fuse. So although the fuse was visually intact it wasn't conducting. A new fuse and a bit of pliers love on the holder and the gas sprang back to life. All it took was a methodical approach to the system checking one item at a time. :)

[lars04]

And today I got one just the same, "Gas don't go, haaalp!!!" on an old Hilux, fortunately his petrol system was still working just well enough to get to me. Turned out that the line fuse for the LPG was somewhere under the bonnet, and the holder's lid had fallen off. The fuse had got wet and corroded slightly and there was a tiny bulge in the plastic body of the fuse. So although the fuse was visually intact it wasn't conducting. A new fuse and a bit of pliers love on the holder and the gas sprang back to life. All it took was a methodical approach to the system checking one item at a time. :)

So have taken a few pictures, I've got power at everything but the picture you see with my finger pointing to the red wire there is no power which leads to the tank which I don't understand as I have power at the start of that wire in the engine bay?. I ran a wire straight from the battery to that wire and I get a click on the solenoid in the engine bay but not at the tank.

[lars04]

Picture of solenoid in engine bay

[lars04]

And also this mess which is wired to the system and into the car most of the solderd spots were wrapped with cloth tape

[bee utey]

That looks exactly like the Hilux system that I had in this morning, same dodgy fuse holders too. There should be a line fuse between the front end and the LPG tank solenoid for servicing purposes. Take all the fuses right out and test them with a meter, or just replace them with new ones.

Dodgy gas fitters also like using crimp terminals under the vehicle without waterproofing. It's quite common to see the earth point for the tank solenoid screwed to a thin panel with a small tek screw. These need undoing and soldering to a wire extension that can be earthed inside the vehicle, eg behind the light cluster. A tek screw should only be used into a double layer of panel. If outside, an earth point needs to be covered in a mound of neutral cure silicone sealant.Any inline connection in a wet zone should be soldered and securely covered in heat shrink or quality tape. Dodgy gas fitters use bullet connectors loosely crimped to thin wires, which of course is a recipe for future problems. :)

Oh and the "mess" is the injector cut wiring to stop the injectors firing, which won't stop the gas running.

[lars04]

That looks exactly like the Hilux system that I had in this morning, same dodgy fuse holders too. There should be a line fuse between the front end and the LPG tank solenoid for servicing purposes. Take all the fuses right out and test them with a meter, or just replace them with new ones.

Dodgy gas fitters also like using crimp terminals under the vehicle without waterproofing. It's quite common to see the earth point for the tank solenoid screwed to a thin panel with a small tek screw. These need undoing and soldering to a wire extension that can be earthed inside the vehicle, eg behind the light cluster. A tek screw should only be used into a double layer of panel. If outside, an earth point needs to be covered in a mound of neutral cure silicone sealant.Any inline connection in a wet zone should be soldered and securely covered in heat shrink or quality tape. Dodgy gas fitters use bullet connectors loosely crimped to thin wires, which of course is a recipe for future problems. :)

Oh and the "mess" is the injector cut wiring to stop the injectors firing, which won't stop the gas running.

Thanks mate, I'm pretty sure the only fuses are the ones in the picture, a couple of more questions I noticed today that when I turn the car over the lights on the switch the yellow and green lights go away that's doesn't always happen also what would happen if the immobilizer was playing up.

[bee utey]

Thanks mate, I'm pretty sure the only fuses are the ones in the picture, a couple of more questions I noticed today that when I turn the car over the lights on the switch the yellow and green lights go away that's doesn't always happen also what would happen if the immobilizer was playing up.
Aha! Your ignition isn't supplying a run signal to the gas controller. Therefore you probably don't have spark or the signal wire has fallen off the coil. Try checking/hotwiring the +ve side of the ignition coil and see if this makes it go. If there is power at the coil but no spark your ignition module may have died. See here (https://www.aulro.com/afvb/technical-chatter/96950-lucas-ignition-amplifier-replacement-bosch-024-a.html) if that is indeed the case.

[lars04]

Aha! Your ignition isn't supplying a run signal to the gas controller. Therefore you probably don't have spark or the signal wire has fallen off the coil. Try checking/hotwiring the +ve side of the ignition coil and see if this makes it go. If there is power at the coil but no spark your ignition module may have died. See here (https://www.aulro.com/afvb/technical-chatter/96950-lucas-ignition-amplifier-replacement-bosch-024-a.html) if that is indeed the case.

When you say hot wire is that from the batt to the +ve? And I checked for spark yesterday and there is a spark at the plugs.
Thanks for your help mate I do appreciate it.
Lars.

[bee utey]

When you say hot wire is that from the batt to the +ve? And I checked for spark yesterday and there is a spark at the plugs.
Thanks for your help mate I do appreciate it.
Lars.
Yeah, that's what a hot wire should do. The immobiliser cuts this feed too from memory. A test light at this point will show that power is always present during cranking.

Look for a wiring connection from your ignition coil -ve post to the AEB controller box. That's how they usually get their signal to run the gas solenoids.

[lars04]

Yeah, that's what a hot wire should do. The immobiliser cuts this feed too from memory. A test light at this point will show that power is always present during cranking.

Look for a wiring connection from your ignition coil -ve post to the AEB controller box. That's how they usually get their signal to run the gas solenoids.

There is a wire going from the -ve to the box, so when I have ign in the on or acc position I'm getting power could it change when I crank it?

[bee utey]

There is a wire going from the -ve to the box, so when I have ign in the on or acc position I'm getting power could it change when I crank it?
When you crank it the -ve coil terminal should pulse because that is how an ignition coil works.

[lars04]

Just thought I'd ask I'm not being lazy haha battery is dead so can't test it until tomorrow.

[lars04]

When you crank it the -ve coil terminal should pulse because that is how an ignition coil works.

No worries, cheers mate.
Now I will be getting my new fuel pump in the mail soon I'm hoping that the gas problem won't happen to the fuel too. Could the same problem happen with that also. Just note that I have spark and power going to the pump plug.

[bee utey]

Another possibility that has occurred to me is that your gas tank solenoid may have developed an internal short circuit. It would cause the controller to go into protective mode when starting. Try shoving 12V down the power wire to the gas tank and see if this operates the solenoid. Sometimes the anti-spike diode in the solenoids develop a short and a decent current surge just blows up the diode. The coil part still works fine after that.

[lars04]

Another possibility that has occurred to me is that your gas tank solenoid may have developed an internal short circuit. It would cause the controller to go into protective mode when starting. Try shoving 12V down the power wire to the gas tank and see if this operates the solenoid. Sometimes the anti-spike diode in the solenoids develop a short and a decent current surge just blows up the diode. The coil part still works fine after that.

Yea tried that mate still nothing, they both click on but seems like there is no gas?

[bee utey]

Yea tried that mate still nothing, they both click on but seems like there is no gas?

Another possibility is that the plunger inside the solenoid valve at the tank has a failed rubber seat. Turn off the tap firmly, undo the 8mm hex bolt on the coil and remove the coil, undo the 17mm hex brass barrel nut that contains the plunger. The rubber seat may have a hole in it cut by the brass seat it rests on. There will be a tiny rubber slug sitting there blocking the flow if this is the case. Don't refit the plunger to the solenoid and don't damage the o-ring as you assemble the valve barrel. This is a temporary fix to get you going. The plunger is exactly the same as many other gas valves so easy enough to replace so it remains safe. Use some soapy water for leak checking and of course no naked flame anywhere nearby.


https://www.aulro.com/afvb/attachments/lpg/118180d1483497115-cant-start-car-lpg-all-sudden-imag0124.jpg

Or there is the possibility someone turned off the tap while you weren't looking...

[lars04]

Another possibility is that the plunger inside the solenoid valve at the tank has a failed rubber seat. Turn off the tap firmly, undo the 8mm hex bolt on the coil and remove the coil, undo the 17mm hex brass barrel nut that contains the plunger. The rubber seat may have a hole in it cut by the brass seat it rests on. There will be a tiny rubber slug sitting there blocking the flow if this is the case. Don't refit the plunger to the solenoid and don't damage the o-ring as you assemble the valve barrel. This is a temporary fix to get you going. The plunger is exactly the same as many other gas valves so easy enough to replace so it remains safe. Use some soapy water for leak checking and of course no naked flame anywhere nearby.


https://www.aulro.com/afvb/attachments/lpg/118180d1483497115-cant-start-car-lpg-all-sudden-imag0124.jpg

Or there is the possibility someone turned off the tap while you weren't looking...

Haha! No one turned the tap off, I'll give that a go today and let you know how it goes.

[lars04]

Another possibility is that the plunger inside the solenoid valve at the tank has a failed rubber seat. Turn off the tap firmly, undo the 8mm hex bolt on the coil and remove the coil, undo the 17mm hex brass barrel nut that contains the plunger. The rubber seat may have a hole in it cut by the brass seat it rests on. There will be a tiny rubber slug sitting there blocking the flow if this is the case. Don't refit the plunger to the solenoid and don't damage the o-ring as you assemble the valve barrel. This is a temporary fix to get you going. The plunger is exactly the same as many other gas valves so easy enough to replace so it remains safe. Use some soapy water for leak checking and of course no naked flame anywhere nearby.


https://www.aulro.com/afvb/attachments/lpg/118180d1483497115-cant-start-car-lpg-all-sudden-imag0124.jpg

Or there is the possibility someone turned off the tap while you weren't looking...

YOU BEE UTEY!!!!!!!!!! so did what you said but still didn't start buuuuuutttttt as I put it back together I noticed that the solenoid didn't move around like the one in the bonnet so I checked the nut on the top of the one in the bonnet which a earth is attached to and I could undo it with my fingers I tightened the bugger up and vroooooom she sprang to life!!!!! Very happy now thank you so much for your help!! I've also re soldered all connections and put heat wrap on them too and hopefully this weekend I will be replacing the crappy inline fuses with better water proof ones.