jarance;546185 said:
MAF = Mass Air Flow meter
AFM = Air flow meter
Usually E46 used MAF whereas E36 use AFM. However, some E46 still use M43 engine so may still use AFM.
AFM and MAF both measure the air volume flowing into the throttle body. MAF use two wires heated up to ense the air flow whereas AFM use vane to detect the flow.
AFM have a tendency to be sticked up at fully open position. When it is fully open, it give the wrong signal to the ECU and hence will cause idling speed problem. Similarly, MAF have a tendency to get coated with dirt and cause the reading to be in-accurate which also cause the idling speed problem.
If you have low power at low rpm, chances could be the following:-
1. chocked fuel fuel filter.
2. faulty pump.
3. faulty plugs
4. O2 sensors
There are many things affected fuel consumption. If you can listed up what you have done, maybe we can shortlist the likely cause.
thx for ur advices shifu! and this is the things i did last month:-
01) changing spark plugs fo - 4pcs
02) pulse generator - 2pcs
03) crankshaft sensor - 1pc
04) rubber boot with resonator - 1pc
05) O ring - 14pcs
06) insert with roller cover - 1pc
07) profile gasket N42 - 2pcs
08) chain tensioner guide rail - 1pc
09) slide rail - 1pc
10) gasket 46 N42 - 1pc
11) oil filter ox166 - 1pc
12) rubber mounting - 2pcs
13) water hose - 1set
14) water expansion tank - 1pc
15) bottom hose - 1pc
16) exhaust pipe bracket - 1pc
17) exhaust rubber mounting - 1pc
18) trunk lid grid with key buttom
19) engine top gasket - 1set
20) oil separator - 1set
21) delivery unit R46 - 1pc
22) engine top overhaul - 1job
23) exhaust centre box - 1pc
24) injector valve - 3pcs
25) lock clamp - 5pcs
26) blower high setting x5 - 1pc
looking for further advice, thx!