No Power on My M40 Engine
I have M40 engine on my e36 93 model, The car started to loose power slowly then after a couple of days just lost it, it can't go any where with the airflow meter i have to remove the 5 pin switch then it can move but with a very little push on Accelerator pedal once I push it more I’ll hear a back firing sound, I have tested my airflow meter to other car and is working fine and changed my plugs. When the engine is cold I have to start it 5-6 times. Now it's eating my fuel big time and it's very difficult to reach the speed of 80KM/h. Recently before that, I just find out that I don't have a return fuel line it is not working, the pressure will build-up on Forward fuel pipe line and can't start until I’ll open the fuel pump and bleed off the fuel. I just fitted the engine last year august with just less than 60 000 KM Mileage import from china. What could be this Problem? It feels like there's air leakage but I couldn't find one, It’s like when I’m putting more air the mixing of air-fuel is not controlled
What could cause this Problem please Advise?