标题: 【1999 Toyota Vitz 】发动机灯亮了 电脑扫描出的结果是:p0171 toyota fuel trim too lean bank 1 [打印本页] 作者: xli422 时间: 2015-5-15 16:21:42 标题: 【1999 Toyota Vitz 】发动机灯亮了 电脑扫描出的结果是:p0171 toyota fuel trim too lean bank 1
【1999 Toyota Vitz 】发动机灯亮了 电脑扫描出的结果是:p0171 toyota fuel trim too lean bank 1
大伙给点建议 到底是哪里出了问题 网上查了 找到这些:
Trouble Area
Air induction system• Injector blockage• Mass Air Flow (MAF) meter• Engine Coolant Temperature (ECT) sensor• Fuel pressure• Gas leakage from exhaust system• Open or short in A/F sensor (sensor 1) circuit• A/F sensor (sensor 1)• A/F sensor heater (sensor 1)• Integration relay• A/F sensor heater and integration relay circuits• PCV valve and hose• PCV hose connections• ECM
A code P0171 may mean that one or more of the following has happened:
•The MAF (Mass Air Flow) Sensor is dirty or faulty
Note: The use of "oiled" air filters may cause the MAF to become dirty if the filter is over-oiled. There is also an issue with some vehicles where the MAF sensors leak the silicone potting material used to protect the circuitry.
•There could be a vacuum leak downstream of the MAF sensor
•Possible cracked vacuum or PCV line/connection
•Faulty or stuck open PCV valve
•Failed or faulty oxygen sensor (bank 1, sensor 1)
•Sticking/plugged or failed fuel injector
•Low fuel pressure (possible plugged/dirty fuel filter!)
•Exhaust leak between engine and first oxygen sensor
Possible Solutions
A lot of times, cleaning the MAF sensor and finding/fixing vacuum leaks fix the problem. If you're on a tight budget, start there, but that may not be the fix for certain. So, possible solutions include:
•Clean the MAF sensor. Consult your service manual for it's location if you need help. I find it's best to take it off and spray it with electronics cleaner or brake cleaner. Make sure you are careful not to damage the MAF sensor, and make sure it's dry before reinstalling
•Inspect all vacuum and PCV hoses, replace/repair as required
•Inspect all hoses and connections in the air intake system
•Inspect and/or test the intake manifold gaskets for leakage
•Check for a dirty fuel filter and proper fuel pressure
•Ideally you'll want to monitor short and long term fuel trims using an advanced scan tool
•If you have access, you may want to run a smoke test 作者: javing 时间: 2015-5-27 23:49:54
If system is rich you can check the spark plug and coil see if it's firing or missing...
If the system is too lean, there's nothing much you can try, I will check the A/F ratio with wide band sensor see if the reading is right or there might be a fault. AFM could be a problem but I don't see Vitz with this problem EXCEPT boy racer putting an aftermarket air filter in.
ECU fault? nah... they don't die easy... I would still focus on the Oxygen Sensor, to save your money you can always try one from your mate who got the same car.
Finally, if you don't know what you are doing, pass it to your local workshop, with a quotation before you go ahead. this job could be somewhere around $150-$300 with replacing new O2 Sensor. (After Market Bosch, or even Genuine Toyota one)作者: 会员 时间: 2015-5-31 16:50:31
Normally you need to do the scope (waveforms) tests for the oxygen sensor, MAP to verify the fault code.
Then do the fuel pressure test (fuel pressure regulator could be wrong)
There is no OBDII in this car so you cannot check the short term fuel trim or long term fuel trim data. The only way we can do is to use the equipment to check if the signal problem or mechanical problem. Then use the common sense to analyze what would cause the lean mixture (more air less fuel).