self learning ecu?????

new to this so here goes.
just bought a 2000 d2 V8 with an AG lpg conversion. after a couple of days it wouldn't run right on gas. felt like a rev limiter/ fueling at 2500rpm especially under load. next day petrol the same . changed airflow meter(this forum is great) and although much better ,but still not right.
I'm pretty sure its the coil packs / leads which i'm changing next week. Thats the royal we as the inlet manifold has a 30mm spacer to fit the lpg so you cant get to the coil packs. I spoke to the lpg guys who serviced it last and they remembered the car and said they had recommended that the adaptions were reset .Had this done and 17 faults logged , misfires causing emmissions / catalyst problems mainly plus maf fault and lambda faults. hence coil packs / lead changes next week (they are originals and the car has done 100k)
i'm worrried that the ecu is now learning from a misfiring engine and the faults will just reappear and stop the ecu fuelling properly. (to be fair its not a full on misfire , more of a hesitation when accelerating and a shudder at 50-60mph when torque converter locks and the engine is under load.)
the idea was to reset adaptions drive on petrol for 50-100miles and then get the lpg tuned.
do you think i'll need to reset again once i've had the packs done and will this affect the lpg (again)
any help would be appreciated especially if there is someone with a test book in the surrey / sussex area.

i would get it running good on petrol first then worry about lpg, often the leads can cause problems with missing etc, get good quality leads and give it a try. if its the same then look at the coils!

thanks Gavbiggs I'm going to replace packs and leads simply because you have to take off the inlet manifold to get to them. I'd be gutted if i changed leads and then had to do it all again for packs. my biggest problem is finding a landy specialist who will work on lpg as well and who has the diagnostic kit. I've had the fault codes cleared and the adaptions reset , but i dont know if they have reappeared as soon as i left the dealer?
Have to see what happens next week

try insideout 4x4 in capel. Not sure if he does lpg stuff but prob worth giving him a ring anyway. Insideout 4x4 Parts, Servicing & Repairs - Off-road vehicles, Land Rover, Range Rover, Jeep, Toyota - Surrey, UK

any news on this one, i'll be interested to know what is causing the problem!

well, the coil packs and leads seem to have solved the problem. I have been for a week in cornwall and running around about 1000 miles and it seems much better. 17mpg on the run down there and 12mpg running around whilst there .(on gas) I do still have a slight judder at 40mph / 1250rpm but this is fuelling not electrical i'm sure. I have spoken to lpg garage and i'm going back for them to connect the laptop and have a drive around. they say the injectors are quite old for lpg (60k / 5 years) or it could be a lambda sensor as this was a fault code that showed before. will let you know what happens.

Will try insideout as capel is only 20mins from me cheers.

its good to know your getting it sorted! you sound happier with it and the mpg seems around the right figure!!!

went back for drive around with the laptop connected and as we thought it showed both front lambda sensor faults, hence poor fuelling at low revs. the diagnostic light was a loose pressure switch connection (?????) 30 secs with a pair of pliers and it seems to be sorted . Hats off to Medway Dual Fuel in rochester , friendly and helpful , good customer service. highly recommended.
Have ordered 2 used lambda sensors off ebay for £40 so hopefully thats the engine sorted. Just the leaking sunroof to sort now!!!

glad to hear your getting sorted!!