EL LPG Idling problems on LPG - Ford Forums - Mustang Forum, Ford Trucks, Ford Focus and Ford Cars

ELwilldo · 06-29-2004, 05:50

I've got a '97 EL Falcon, that's been converted to LPG. When I got it, the fuel injectors weren't even connected, and I haven't found 3 of the plugs yet! It's an ex taxi, running a Landi convertor.
When I first got it, the idle was erratic, and I smoothed it out just by playing with the idle and diaphragm screws. Yesterday, my missus left it with me, saying she couldn't drive it, as she went to work and almost got featured on the traffic reports on the radio, 'cos it was stalling at idle.
Anyway, I got the manual, set the base idle, turned it off, removed the jumper from the diagnostic connector, started up to an idle of about 2500 rpm. (At least it didn't stall!)
I repeated the prescribed procedures, and sometimes it would work, take it for a drive, then it'd be revving high.
I made up a LED test light, and got a power steering pressure switch open circuit fault, then I assume in the memory, a MAP sensor out of range, and ECU reference voltage low.
Are the memory readings (codes after the single flash) past faults that may have been fixed and not cleared somehow, or can they indicate a current problem?
I've just put in a new air/oil filter, the plugs look sexy the way they burn, I might have to fork out for new leads (don't know how old they are) and the engine runs great on the run.
Any ideas on the memory codes? Shall I get the MAP sensor too?

EFFalcon · 06-29-2004, 15:45

not overly helpful with the codes, but my EF was having idling issues on lpg at one stage, if at anytime i was going from ~80km/h to under 5km/h the revs would drop to below 300rpm, it'd splutter and occasionally stall (not good when turning) it ended up being as u said the idle screw on the LPG Converter, it has a habit of adjusting itself (weak spring) and so needs adjusting every now and then.

ELwilldo · 06-29-2004, 16:29

Actually, since you mentioned it, I did notice a power cut when doing a left turn the other day - I'll have a look at the convertor when the car gets home this arvo. It seemed to start ok this morning, and I haven't got any burns back from the missus after she got to work.

ELwilldo · 06-30-2004, 05:17

The boss got home after dark, says that it didn't stall, but was idling rough. She accepted THAT because of the cold. I've done a bit of research since, and found I can reset the codes - which can point me to those bloody intermittent faults!
But, the diaphragm I was adjusting is a standard Ford item. I can't find any reference as to how this should be set. It's located on the front left side of the motor (from driver's seat viewpoint), has a vacuum hose going from the top to the nether regions. I can't find a way to set this, apart from ear... too much either way and when you rev, it hangs on too long...

ELwilldo · 07-03-2004, 04:30

Car's still running like crap. I've decided to go to grass roots, work off base idle and try and get the gas convertor set up properly first, before the Ford idle screw, see if I can get it working ok that way. I think the power steering pressure switch is defininately on the replace list, though. At the moment it's hunting when at idle.
It'd be great to know a way to tune both the LPG and the ECU idle in harmony!

d_slayer · 07-04-2004, 06:52

Don't know if this helps but if you email me at eafan@dodo.com.au.. I will send you a few scanned landi computer pages that I have for my landi unit but I found the best way of setting the gas mixture is via a air/fuel meter.. as the gas computer only gets readings from the tps and the OS

fairmont1998 · 07-04-2004, 07:41

Does your gas system have the tube that runs from the converter to the air box? If this tube is disconnected it will idle like a dog.

ELwilldo · 07-05-2004, 04:52

Fairmont1998,
I've just gone out to check under the bonnet, and there's no tube going to the airbox. There's a brass nut on the top left side of the converter (looking at the idle/mixture screw side) apart from that I can't see where a tube might be fitted. (Only looking by the light of a small torch!)
This car was not manufactured with LPG, where in the airbox does this tube go? I assume somewhere on the clean air side, but that'd be close to where the gas goes into the air inlet. The gas is connected to a fitting after the airflow meter before the phlenum chambers.

ELwilldo · 07-06-2004, 03:17

D_Slayer, thanx for the email. I've got those pages now, I'll have a look through them once they've printed out.

ELwilldo · 07-11-2004, 03:21

I've fixed the problem! There were a few things I've rectified, and now the engine's running smoother than I've ever seen it.
I replaced the power steering pressure switch, 37 bucks from Repco.
I had a talk to a taxi mechanic, he told me that on the Landi convertors, the balance line (from the convertor to the airbox) didn't seem to make any difference. I described to him how my LPG system had been fitted, and WHERE the gas line was fitted to the air intake. Mine had a hole drilled in the rubber part of the air intake pipe, closer to the firewall. He showed me the spot next to the throttlebody where it should go. So off to the wreckers to buy another rubber air pipe section (40 bucks from the wreckers).
Once I made a new hole and moved the mixer, I went through the idle-setting process, then went for a drive. The engine was a lot more responsive, and felt better, but still had a high idle.
I went through the key-off diagnostics - all clear! But the engine running diags gave me the Map sensor out of range. So, with the engine running, I started looking for air leaks around the engine, with my trusty can of ether spray! When I gave a squirt near the firewall, the engine gave a rev, and I found a dodgy hose coming off the Map sensor.
Once I fixed that, reset the idle - I couldn't believe the difference! Just to be certain, I gave the ISC a good clean, too.

So thanks, guys! The suggestions you made got me asking questions, and looking around, and fixed the problem. Now I've got to give the car back to the missus, and get used to being back in my ole' diesel ute