You don't say the make of your system but most sequential systems have a feature that will force a temporary switch to petrol if the LPG injector open time is greater than, say, 25mSec. This is to ensure that the engine doesn't run lean under this condition. Conversely a pressure drop below a certain point will force a "permament" switch back to petrol until reset.Hello all, been following this thread with interest and thought I'd lob this in to the pot.
I have noticed on a couple of occasions that after a bit of "spirited" overtaking, I am back on Petrol for a second or two. Yesterday I had a chance to explore further and found that at 5000rpm approx it switches over to petrol especially is provoked by a good hard prod on the throttle. I am wondering if the info from the lambda sensor if freaking out the gas system at those revs (ie. it can cope with up to 5k rpm but is not expecting anything higher) or it just canot supply enough to the engine at that rev. range? Interesting and maybe someone on the boards has an answer?
BTW, it's an MG ZT 160 V6