I am the owner of Mazda Demio '02 1.5 75HP (engine code B5E). The car has an issue of high RPMs (more than 1000 and hestitating) on idle. What is interesting here is whenever I press and hold the clutch RPMs goes down and are stable at the 800 RPMs level. It happens on cold and warmed engine as well.
I have ODBII scanner and I noticed that when RPMs goes high the amount of air gathered from the MAF sensor increase. Its also worth to point that whenever a clutch is pressed the status of the fuel system is in closed loop and when depressed in open loop.
FYI recently I replaced the oxygen sensor and was manipulating throttle position sensor and the latter I believe is the issue of te abnormal engine behaviour. Could someone confirm my thoughts or direct me to a solution?
PS. How can I perform throttle adjustment?
PS2. The check engline light is on and the error code obtained from scanner is P0507.