Guys , I have a Mitsubishi Lancer 2005 model, 1600 cc manual transmission.
The car was running really fine both in petrol and CNG but it started getting heated up 3 months back and there was engine oil in the radiator and upon getting it checked with the mechanic, he said that Head gaskit has to be changed. Simultaneously , the car started giving dense smoke , for which the mechanic said rings need to be replaced as they had became week. I got the work done and car was fine but on petrol, the car started missing , when i lift my foot from accelerator to change the gear, the car gives unusual 'jhatka' and gives mild 'jhatka' also when i push the accelerator. But on cng, there is no problem of missing at all and it runs really smooth and the drive is very smooth and pickup is excellent as well and mileage is superb too.
Now the problem is that if i get the CNG Cylinder full, the car automatically turns back to petrol ater driving 1-2 km after getting CNG full.
Then i turn off the engine, wait for 10 minutes and then start it again' it converts normally from petrol to CNG but after running it on CNG for 1-2 km , it gets back to petrol automatically again and doesnt convert to cng even upon turning the switch to petrol position and then turning it back to cng again.
However, i have noticed that when after consuming all the CNG , i get gas worth Rs. 200-250 ie Half the capacity of the cylinder, the car runs very fine and doesnt convert back spontaneously to petrol. It runs very fine if i dont get my cylinder full but only upto 50- 70 % of its capacity.
I have got the fuel sensors checked as well and got the cng kit serviced and cylinder serviced as well but to no avail.
Kindly help me as no mechanic so far has been able to solve my problem
Regards.