loss of power on auto switch over

[fidel]

Hi, seasons greetings to one and all.

I have a 1999 V70 2.5 Torslander with a Zavoli regulator and Stako tank fitted. When usingit yesteday I noticed when it auto changed over to LPG after starting there was a loss of power for about one second then ran fine on LPG, the car did this twice each time after starting. Any ideas??

Could it be a low amount of LPG?? as I also noticed that the gauge sometimes had two green lights showng then at times one red light.

[JezF]

Could be a few things, low pressure being one of them. My gas system came off recently for a PCV renewal, the injector cables had been swapped over by accident on two of thje cylinders, this caused exactly the same problem.

[jrtonks]

The problem is likely caused by the cold weather. When the engine switches to LPG, there is usually some cold or partially liqified gas still lurking in the injector piping etc (post vapouriser).

Your car is probably switching over too early. Your LPG fitter might be able to amend the switch-over temperature, depending on the system fitted.

The easiest solution is to manually switch to petrol and then manually switch to gas once the engine is a bit warmer and whilst you are driving at 30MPH+ (i.e.not whilst idling).

Worth a try.

[capt jack]

Had exactly the same yesterday. The car had been left standing for 3 or 4 days in very cold temperatures, I started up on petrol, then the system switched over automatically to LPG after a couple of miles, but before the engine had thoroughly warmed up. A very rough idle at the first roundabout prompted a switch manually back to petrol for a few minutes. When the temp gauge reached the mid point I switched back to gas - and it was fine from there on.

A similar thing happened a couple of winters back, and the fitters just altered the switchover temperature.

I think the advice to switch over on the move and not at idle is a good idea - nothing more disheartening than to try to pull away only to find the car has other ideas!

Jack