I have a dedicated Gas AU3 and last week had a new convertor fitted as the old one was taking in air and then leaked water so froze up.

Now the new convertor is on, at the workshop started great short drive all good. Now when I start it coughs and s*** after a short drive comes good but might have a small cough at lights. But during driving occasionally it strarts going all rough, while I was driving it seemed like it lost acceleration a couple of times and when I put my foot down backfired, this happened 3 times and then come good again. It stalls occasionally on what seems low revs such as going around corners and today it was coasting along down a slight hill and when I hit the accelerator again it stalled.

It seems when I fix one thing another issue immediately arises, not sure if time for a new mechanic , new car or this might be something minor.

Any advice?

What converter did they fit?

Vialle. After driving it tonight the engine feels like it is pulling occasionally, but while driving.

Plugs? Leads? Coil? Battery? Everything else ignition-related? Oxygen sensor?

I to have an Au gas engine. And have had dramas with the LPG settup since day 1.

The first time a similar thing happened the flexi hose on the intake was split at the ends and was sucking air in from there and not from the snorkle where the LPG air flow sensor is. So the computer was stuffing up the LPG/air ratio.

So look for cracks or air leaks in your intake.

it's been at the mechanic for 2 days and since I'll be away 2 days he'll have it all week. Plugs Leads Battery recently replaced (although could still be faulty), coil checked. Did think it was o2 and replaced but didn't work. He is baffled and now thinks the new convertor may be dodgy so will replace that on Monday.

When i had both my cars put on gas the new converters needed to be worn in for 1500K's and then re-tuned again. I had 2 faulty converters on the BA so that needed to be tuned heaps.

after testing everything he originally thought the o2 sensor, but that didn't work. The Coil tested OK, but after a few days he replaced it to chack and all is good....aparently. I am yet to pick it up.

Coil Pack it was, running OK for a few days now.