I think I may take it to the Prins guys in Southampton
I spoke to them today (on different subject), got the impression they deal with Prins diesel blend systems now, Prins petrol systems dealt with in Huddersfield.
You needn't splash out on an all new system...
the battery on the car started to play up a few weeks back and so I replaced it, afterwards out of curiosity I thought I would try the LPG again and it worked !
Maybe disconnecting the battery cleared fault codes and allowed the system to work, not sure but I managed to get through 4 tanks with no problems.
Maybe battery connection cleared codes, maybe you made a better power connection for the LPG system when reconnecting, maybe just coincidence.
This week the system is playing up again, only difference being the temperature. If I leave the system to automatically switch over it cuts out and drops one or more cylinders. If however I let the car get much warmer and switch it over manually it seems to run quite happily
Does this point conclusively to the reducer or plumbing not being right ?
Maybe it's set to changeover at too cold a temp like Gilbert said, and Mercs do shut cylinders off on misfire detection. From memory, Lovato has a min setting for changeover temp of 20c and this weather your engine will have been running a while for reducer to reach 20c? if reducer plumbing was an issue would expect to see problems after running on gas a while, not during switch-over. Other possibles would be long injector pipes, manifold nozzles in poor location, ECU settings issues such as fuel switch-over characteristics, incorrect temp correction, poor mapping, some injectors don't work well at cold temps. It is possible to mask most such issues by setting a higher changeover temp and/or setting changeover in deceleration at higher than tickover rpm, where if install was on par that shouldn't be necessary.
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