i have a lpg conversion on my 2.8 v6 and its been on 2 years. i am getting a problem with the idling of the car. it is rough but not to the point of stalling. it only happens on lpg and i have plugged it in and it comes up the codes

P1128 BANK 1 TOO LEAN
P1129 BANK 2 TOO RICH
P0150 BANK 2 SENSOR 1 MALFUNCTION

I thought it could be a lambda sensor so they got changed but no difference.

Has anyone else got a conversion and do they suffer from the same problem, i havent had the car long and its still a bit new to me but something dosent feel right!!

Is it possible that the ECU cannot react quick enough to the gas for mixing?? Ive cleared the codes several times and no codes appear when runing on petrol but its an expensive hobby to run on petrol al the time!!
Any help would be much needed and appriciated

 

Is that the oxygen sensor that was replaced? That could cause the issue you describe. Unfortunatly im not really familiar with lpg at all, but considering that it only happens with the lpg, i would look into a problem with the lpg delivery system, or the system that controls lpg delivery.

 

yes the o2 xensor that was replaced was the one that brought up the fault code. since then, i have found out that LPG conversions PRE 2003 have a slightly slower ECU return rate and tick over will never perfect. that is probably why it brings up mix too rich and mix too lean because it cant get the LPG to richen up or lean it off quick enough so all in all no problems!!