Car information
Car of Ao Di A8, configuration V8, 4.2L engine and automatic transmission, travel course of development makes an appointment with 50 thousand KM.
Breakdown phenomenon
Engine idle fast shake apparent, low speed area is quickened not free, vent-pipe blowouts, but high speed area (3000r/min) movement is basic and normal.
Breakdown reason
Ageing of mat of the manifold that take energy of life, rupture.
Breakdown is diagnosed
1, undertake be checkinged basically to engine, unusual without discovery.
2, change fuel filter, test-drive, breakdown as before.
3, use diagnostic appearance to undertake be diagnosticed oneself to engine system, have a malfunction code 16486, the meaning is signal of air flow transducer too small.
4, examine data to flow, air flow signal is not stable, this is not stabilized with engine itself movement probably about.
5, change air flow transducer, cleared malfunction code, breakdown did not improve.
6, information of new inquiry breakdown, without malfunction code, air flow data and former basic and identical.
7, examination air filter arrives the pipeline of the manifold that take energy of life, take off a phenomenon without the pine.
8, with carburettor Qing Dynasty lotion eject enters gas manifold, engine response is apparent, the specification has flat problem, microscope, discovery fills up ageing into gas manifold, rupture.
Breakdown processing
Change to be filled up into gas manifold, breakdown eliminates thoroughly.
Case proposal
The feature with this exemple the most apparent breakdown is low speed area is quickened not free and high speed is normal, this specification breakdown and fuel pressure, ignition when have nothing to do.
Idle fast shake often concern out of order with mixture gas, and malfunction code the generation of 16486 is as flat as the manifold that take energy of life about.
Eject carburettor clear lotion is the method of leak hunting, combustible solvent is entered combustion is participated in inside air cylinder, engine response is apparent, because this can prepare the ground,find leakage place.
