LPG Discussion Forum

We could probably theorise all night and, if we wanted to do lots of maths involving the relative weight of petrol vapour, LPG vapour and air, it might be possible to calculate the exact quantities of each, but it's now cured so why worry too much?

I don't want to launch into theory nor prove I ...

The LPG has a lower calorific value, so we need more fuel to hold the same level of RPM, which also means we need more air. No you don't, you need the same amount. For this reason, the LPG controller needs to supply more fuel than if running on petrol, hence the fiddle factor of increasing the ...

We saw some improvement after cleaning the IAC valve but then somebody passed me an article from Morgan about GEMS pointing out the piece about the idle mixture screw.

I had no idea what this mixture screw was, or even existed. I do now.

When I read the article I suddenly realised there was ...

I've had high idle on my P38 before which was down to a sticky throttle position sensor. Slacken the two screws out that hold it in place, start the engine and if the idle is high, remove it from the throttle body but leaving the wires connected. If the idle drops as soon as it is removed, there's ...

Hello all.
i've been running on petrol and the LTFT's are currently -96. I've also just changed the air filter which i had to wait for, odd size for my year apparently. One thing i didn't mention was that on start up the tickover is sometimes high, sometimes low. I've since learned this is classic ...

I would advise caution interpreting the LTFT from GEMS as reported by generic OBD gadgets - they get it wrong.


I noted on my Easy OBD11 software that the o2 readings were rotating between 0.2V & 1.25V on what should have been 5V sensors. I found a procedure to test them properly at the ECU and ...

Thanks for your input classicswede. I've just today changed the spark plugs back to a new set of NGK BPR6ES from the Autolite Optima 64 plugs i had recently fitted as a general service part, which constantly gave rise to missfire. I drove around 10 miles around town and the LTFT has lurched back to ...

Hello all.
I have a 1996 P38 Range Rover V8 4.6 HSE, 110,000 miles running on a Tartarini sequential LPG fitted by Autogas2000 about 5 years ago. The idle on LPG has been ropy for as long as i can remember now, i've been slowly nibbling away at a solution for the last two years.

The conversion ...

sijones wrote:Please start your own thread including as you have the full car details, lpg system and fault... it helps keep track of help on your particular issue!

Sorry, will do.

Hello all.
I have the exact same issue with a 1996 P38 V8 4.6 Range rover fitted with a Tartarini sequential system, now five years old. Always starts off the key perfectly on petrol but as soon as we changeover to LPG we get this surging, just as the original poster stated, 300-700rpm and stall ...

I believe it's a fully sequential system but although each cylinder does have it's own injector all the pipes come from a central distribution unit that Tartarini call a gas rail matrix. So i have a pair of injector blocks each having 4 pipes running off.
I take your point though, i have stripped ...

Well, i'l bow to your experience as i'm not a computer guy by any means. I'm more hardware than software mainly because i'm a toolmaker by trade so all my disciplines have a mechanical bias. My LPG system isn't that bad, tickover is a little lumpy and will stall occasionally when cold, but that's ...

I found a fella selling the Tartarini software on Ebay and he said he would supply the details for the hook up cable. There was a load of stuff on this CD, lots of different software but mine was there. The cable details were in the Tec 99 manual.
I've copied and pasted that section of the manual ...

All HSS (high speed steel) tools cut a lot better with lashings of oil all over them, stops the cutting edge burning out. Any oil will do, the thicker the better.

Thanks for your reply. It's not just a plain cable then? I'll pop down to maplins in the next couple of days and see if they can help me. Thanks again.

Hello all.
I'm looking for a link cable drawing for my Tartarini sequential LPG. first fitted in 2005 to my 1996 V8 Rangerover. I've got the software and i shall use my desktop so i'm looking to make a cable to connect the ECU's 4 wires (red, white, black and green) to a 9pin rs232. I've found ...