hey guys, quite a story here I have an omvl r90e setup in my EB that hasn't been ran for 6 months now, the old converter was leaking coolant into the manifold so I replaced it with a brand new one and left it out of action until I could afford a reputable lpg mechanic to tune it rather than tamper with it myself.

Well here we are 6 months later I finally got around to getting the gas back in action and was suggested to me the dyno would be more comprehensive and refined compared to the lamda tune through the o2. Although significantly more expensive I went for the dyno since I wanted the end result to be perfect.

Unfortunately I got the car back off the dyno today and it runs far worse on gas than it did 6 months ago... when it had the old shagged converter (of course also an r90e)... So sufficed to say I'm extremely disappointed atm and it's not even safe to drive it's flat spotting/surging/borderline stalling and even leaning out I believe, and it idles poor and hesitates on takeoff. It was perfect with the old converter none of these issues, if any issues besides the coolant loss.. It's like the afr's are out of whack despite going on the dyno.

I'm going to call the guy tomorrow and see what he suggests (he's been terrific and very happy to spend his time explaining the process to me) but I feel this must be something to do with the tune and it was somehow missed on the dyno, but I haven't ran it in 6 months too (I put a full tank of fresh lpg in and no fix). He said bring it back in 3-4 tanks to check the converter diaphragm but it's running so bad I can't even make it until then.

I've pinpointed the cause of possibly all these issues and it seems tune/AFR related.
If I BARELY depress the accelerator (I'm talking as little as humanly possible) while going up an incline or any form of load on the vehicle, the car chokes/dies to a stalling point, as though it's leaning or flooding the motor and the moment I depress the accelerator pedal more than a bees d**k it kicks back in out of limbo and revitalizes.
It's IDENTICAL to when my fuel pump was cutting in and out, causing the car to die/stall in limbo and kick back in seconds later in exactly the same way and feeling.

So that explains all the dangerous surging/jerking back and forth at cruising speeds. I've read this is perhaps a stepper motor issue, but remember it still idles poor (although smooth but still off) and hesitates on takeoff so I'm still thinking the mixtures are wrong. I thought all the afr's and stuff came up on the dyno hence my concern I was given the car back with no mention of these issues, the car's unsafe to drive and I feel im going to lean out my half rebuilt motor, but I'll find out more tomorrow I guess.

I don't see how it could come off the dyno so crudely given the process involved.. without any issues with the car. It's not even tuned really to put in perspective, well I mean I would adjust it in my backyard by ear right now if I wasn't worried about voiding the guarantee.

Id be taking it back to who dyno tested it and tell em it runs like s%#t since the tune, but being left for a period of time and as gas dries out the rubber diaphrams n what not its possible something is perished. On the other hand could be a solenoid on the gas system, one plug I disconnected was under the hood on left hand side going from mixer to airbox and helped mine run better. Try unplugging one by one checking how it runs in between each plug and narrow it down

If this turns up no results I'd be checking your gas pump , dyno tuning involves driving your car fairly hard and as its been sitting a while could've contributed to something breaking down

I took it back the other day and he tuned it by ear quickly, while this made the idle sound nicer lol it now hesitated much worse, he said the diaphragm needs to wear in (new converter) and bring it back in a few tanks for the checkup. But that like I thought wasn't the problem today I found.

I'm really starting to question if it even went on the dyno. I've asked for the sheets over 5 times now, once when I first called up, twice after I picked it up and I've sent like 4 emails for over the week everyday because they said the'yd email them to me last Tuesday (the printer ran out of ink and doesn't look to be getting any soon). I called up on Friday and was told a different story, the computer cant email or print... so if that's the case none of their customers get their sheets lol. I was told I'd be getting the sheet before I even handed the car or any cash over.

And today I discovered a loose wire that broke off months ago, resoldered it and it's fixed everything, the car now actually drives without any surging or hesitation, just needs a proper tune but it's driveable now thank god the way it was with the old converter, and my motor feels like it's not going to blow up.
The wire is black and runs from some important looking solenoid to the gas ecu, the solenoid was flicking whenever I reconnected/disconnected the wire, surely a dyno should've picked up this wire was disconnected? I'm not sure exactly what it does but the mixtures seemed all over the place with it disconnected and it would hardly kick over.

Unbelievable!!!! The C**k that call themselves mechanics these days. You wouldve been better off taking the ar to McDonald's and getting a random opinion haha what a poor setup they must have to if they can't give you results of the supposedly 'dyno tune' and that looks like a ground wire come loose cannot believe that they didn't even pick that up wow!!!