207 1.6 Gasoline Automatic 2012

First of all, Hi everyone, I have a 2012 model 1.6 gasoline LPG automatic vehicle, the car does not go on a flat road or uphill, the flat gasoline does not notice LPG, it does not exceed 160 km, I go up 30/40 la time when the counterparts on the ramps are 80. If I went to the master, it is okay, they say it's fine, they drive me crazy. I changed the coils, spark plugs and cables, again, the same fault lamp does not light, I connected it to the computer, it does not give an error code, I would like to listen to your feedback. Respects.

You've been using the tool I understand for quite some time now the problem has started. If so, how has his vehicle changed recently. Is there a problem such as hard work, vibration, stalling and so on. In addition, the vehicle 1.6 vti.?

There is no problem in his work, it was not very good when I bought it, I already bought it at 12,000 km, and the masters insist that it does not seem a problem at 85,000, the same was the 2011 model, the departure was fine. VTI is correct.