3.5 EFI on LPG won't start

[Spacemud]

Yesterday, after a journey of about 35 miles I stopped to look in a garage and when I started back up I needed three attempts on the key. LPG clicked in after a couple of seconds then all was ok, until............

Stopped again at another garage, when I got back in and tried to start it, the engine turned fine but it wouldn't start on either petrol or LPG.

Before I decided to tow it back home (with the 2a   ) I checked various wires, and took out a plug. Plug indicates that there is no fuel going in.

Any ideas on the best way, and right order to investigate the problem? Obvious thing to check first is the fuel pump but i haven't found it yet!

[hairyasswelder]

pump is in the tank, take the petrol cap off and listen as someone turns it over for you.  I seem to remember the airflow meter switches the pump.
How does you gas switch over? will it start on gas?

[Range Rover Blues]

My LPG will not start until the engine is runnig, it's a safety thing.  In emergencies I run a jump lead from the battery positive to the gas valve under the bonnet to allow a short burst of gas through, then I can start it.

I had the wires to the fuel pump just fall off once, corrosion :roll:

Check the wiring under the back end before starting to pull the floor up.

[hairyasswelder]

mine will start on gas if i turn the ignition on, switch from gas to petrol and back to gas it will purge the ststem and start, usually on the 2nd attempt. If I do this the gas led flashes.
All systems are different, this is a stargas drawthrough systen using relays to shut injectors off. If the relay fails it leaves the petrol switched on.
Early 3.5efi has a fuel relay under drivers seat near ecu,
If the pump is not running try checking for voltage in the wiring before removing pump, if pump needs to come out check boot floor for access panel, if not, as with some early 3.5, the tank has to come off    

Steve

[Garth]

Cant work out if this is the same problem I have but I havent found solution yet either.

On cold morning cuts out on gas approx after 1/4 mile and the only way I can get started is to turn over on petrol with foot to boards for about 2 mins then splutters into life.

[jjsaul]

whereabouts in shrops are you?

[Spacemud]

Couldn't get it started with the purging technique, although just once there was a tiny sign of life.

To be honest I got back late, it was cold and dark, I was tired and the sunny  8-[  bank holiday is on the way. Thought I would wait until everything was easier.

Hi James, i'm in Telford, straight down the M54................."Roads?! we don't have roads, we only use roundabouts"  :lol:

[Rossko]

On cold morning cuts out on gas approx after 1/4 mile and the only way I can get started is to turn over on petrol with foot to boards for about 2 mins then splutters into life.

I'd bet that is down to poor waterflow for the gas vaporiser, classic symptom; when it happens jump out quick to see the frost on the vaporiser and the stink of way too much gas flooding the engine.

Check the obvious - radiator water level, kinked hoses. If no joy think about how to shift any airlock in the plumbing. Check it was installed correctly - the vaporiser should usually be connected across the heater hoses for a full flow.

Sorry, doesn't help poor Spacemuds non-starter. Can only go with the others - check pump runs etc.  Also the little ignition amp module can fail in the way described sometimes, if you've got an EFi distributor; mine did.

cheers, Ross K

[Range Rover Blues]

Added to that Garth, check how the petrol system is cut off, if it's by stopping the fuel pump it may take a while to get it started, otherwise it could be the LPG equivelent of flooded as suggested above,  Either way annoying :?

[Spacemud]

Ok then...........success!!! :D

Worked through everything this afternoon/evening as advised.

Power at the connectors all the way up to the pump, but no fuel coming out and no sound from the tank that would suggest that there was any attempt at pumping going on. So removed the tank to get at the fuel pump and connected it up to prove that it didn't work..........of course when tried it did work! Somehow it was now working fine? :?
Decided to put everything back and try again. Once the fuel was back through the pipes she started no problem.

Solving one problem has created one slight other problem. Seem to have split one of the fuel pipes above the tank so tomorrow looks like it'll have to come at least part way off again. Nevermind, I'm happy again thanks to you lot!

[Spacemud]

Job done now! \:D/

We dropped the tank down again today to find the leak. It was the metal pipe that runs along the front of the tank. It was really rusted so not really that surprised it sprung a leak. Have replaced with £3 worth of flexible hose today and we now have a working vehicle again.

[jjsaul]

i work at gkn at hadley so if you ever want me to pop round after work....

[Spacemud]

Hi James,

That's good to know, I'm in Donnington Wood so close by. Got an eye on that early front grille of yours so when I next get paid I may get you to pop in for a coffee/tea/beer on the way home from work.

Would I ever see you one of your Landy's around Telford?

[jjsaul]

Hi James,

That's good to know, I'm in Donnington Wood so close by. Got an eye on that early front grille of yours so when I next get paid I may get you to pop in for a coffee/tea/beer on the way home from work.

Would I ever see you one of your Landy's around Telford?

Yep, white rangie, 1986 but on a private plate.
Bling ish alloys with BFGs, rusty bottom tailgate, front brooklands bumper with paint missing....!

[Spacemud]

I know where that doublecab lives!

We passed it Tuesday on the way back from the train station (not that I ever notice proper offroaders  :) ). It's on the way out of Wolvo just past the Wergs, isn't it?

Is that yours too?

[Spacemud]

It's playing up again!!! ](*,)

Have dropped the tank three times now as the pump stopped working again (and again). At the moment it is working but when on petrol rather than LPG it idles erratically (is it called hunting  :? ). switch to LPG and it'll idle fine.

Any suggestions as to the reason? Should I have bled the fuel system? Just read through some old posts and realised it may need to be bled. I did have the filter off and changed a couple of pipes so it has been messed about with quite a bit?

Thanks!

[tjsj]

I had a similar problem the other day on mine though Im on carbs and dont have lpg!
I was going up a steep..ish concrete drive and the car decided to loose all power at the top and died, i rolled back down to the bottom as i knew i was low on fuel and had suspected it had ran out but all it would do is splutter then after 30 seconds or so it wouldnt even try to fire.
I then got the tools out and made sure it was sparking and if i put petrol directly into the carbs it would splutter and try to start so diagnosed it as a fuel pump issue, went to find the fuel pump (just next to the passenger trailling arm mount, gave it a tap with a spanner and it started up again, its been running fine since then until today where it stopped 3 times within 1 mile! A quick hit of the pump and off it goes again! Do i need a new fuel pump?

[Spacemud]

Sounds similar to mine, but I can't hit mine without taking it out of the tank  

Think, I'll get another...........secondhand, they are about £75 for a new one!!

[Spacemud]

Took delivery of a secondhand petrol pump today and fitted it this evening (there's nothing I don't know now about removing and fitting a fuel tank, iv'e done it that may times with this one!!!).

Looks like the old pump was dodgy as running on petrol again. Not convinced that the hunting has stopped but that problem can wait as i'm fine on LPG.

[Range Rover Blues]

Is your LPG a draw-through system then?

When ours was hunting/running bad on petrol it was the ECU gone first time around and the ignition advance processor every time after that, when it gets wet it advances on petrol too :roll: .

[Yoshi]

Just an idea for future reference, i will get v8seriesone to post the finer points of what he did, but when we were converting my 3.5efi (i say we, but i was only useful and providing jubilee clips and staying out of the way!) to a 3.5 carb (converted the engine, not a full engine swap) i had a problem of a faulty fuel pump in the tank.

Anyhow, his solution, which was brilliant, was to use an earlier fuel pump, one that attaches to the chassis, and just remove the gubbins from the internal fuel pump so that it can still suck through petrol but from the other pump not the internal one, and then use that, it was faultless and brilliant!

[Spacemud]

Hi, not too sure. It's certainly not a modern one. Has a cylindrical spaceship shaped thing and what looks like a couple of adjustable flow valves  :? It will start straight on lpg with a bit of flicking of the switch back and forth.  

Where would the ignition advance processor be then, and how would I check it?

Many thanks for your help, by the way  =D>

[Range Rover Blues]

Advance processor was psrt of the LPG conversion, not many have it (I fitted my own) but you want to check the advance mech for sticking in the dizzy.