under load on the engine.it will start and drive barley. I changed the mass and map sensor but didn't change anything what do I look for now
My car has an automatic transmission.
From what you describe it would appear that you are experiencing some sort of engine performance issues. Perhaps misfires, or stalling. If you changed the MAP and MAF sensors, and the issue has persisted I would then look into the vehicle’s fuel and ignition systems. It may be possible that one of the components from these systems has failed and is causing an issue.
A few things to look at would be the fuel pump, the fuel pressure regulator, the ignition coil, and the ignition module. Another possibility is vacuum leaks, perhaps due to a bad hose, gasket, or idle air control valve. I would start with the fuel system, and go from there.
If you need help with these checks, consider YourMechanic, as one of our mobile technicians can come diagnose your loss of power and help you make the necessary repairs to get your car running normally again.
Have a car question? Get free advice from our top-rated mechanics.