난이도 & 준비물
증상
I am trying to troubleshoot a 4runner with 135k miles, auto, 3.4 V6 California emissions. This is the freeze data: PID Description Value Units 0x02 Freeze frame DTC P0420 - 0x03 Fuel system status Closed-loop, using oxygen sensor feedback to determine fuel mix - 0x04 Calculated load value 34.12 % 0x05 Engine coolant temperature 197.6 F 0x06 Short term fuel % trim - Bank 1 0.78 % 0x07 Long term fuel % trim - Bank 1 3.91 % 0x0C Engine RPM 2287 RPM 0x0D Vehicle speed 68.97 MPH 0x0F Intake air temperature 95 F So far the front and back Ox sensor was replaced and the MAF cleaned to clear a P0171 co
처리 내용
Has DTC P0171 stayed clear after a 2 trip minimum? Did DTC P0420 come back after it had been erased? The freeze frame short and long term fuel trim is way out of wack. The PCM is trying its best to lean out the mixture but is close to its limit. You will have to find out where the extra fuel is getting into the engine – think leaking fuel pressure regulator, stuck fuel injector, leaking fuel injector, MAF out of calibration, etc. I would be striving to get the long term fuel trim close to 50% before I would condemn the catalytic converter. Can your scanner read the activity of the A/F and o2 sensors? If you have the equipment, use an dual trace oscilliscope to monitor the A/F and o2 voltage wave forms and see if they are similar in rich-lean-rich crossings. My research has led me to unders
출처
이 사례는 CarTalk (미국)에서 수집한 데이터입니다.
신뢰도 2.5점(참고용) — 출처 소스의 전문성/검증구조를 기준으로 산정된 점수이며, 정확성을 보장하지 않습니다.
원문 보기 ↗다른 차종의 냉각수 교환 사례
현대 소나타
Coworker has a 2008 Hyundai Accent, which has overheated repeatedly, consumes a lot of coolant, and barely runs. He wants me to assist with repairing the engine, if possible. I assume by now, the head is warped or cracked, but what I am trying to determine is if the engine block in this model is iron or aluminum. If it’s iron, this can probably be repaired. If it’s aluminum, the entire engine would need to be replaced, which is more work than I would want to do.
쉐보레 말리부
Temperature Guage doesn’t work, fan on motor runs, air conditioner doesn’t work when this happens and message says, “steering assist reduced, drive with caution.” Replaced temperature coolant sensor, still having problem.
포드 익스플로러
Been a long day. Im not good at putting pictures on here. So ill try again. This is on my 89 year old moms ford explorer.its a 2012 she bought new. 3.5 engine. All work has been done at the local Ford dealer. 75k miles. I looked it over and decided to check the air filters and a few other things. I noticed the coolant looks pink, it should be orange. She has ever receipt from the dealer service. Its never had any work done involving coolant. Just tire rotation and oil changes. Sad to say she’s never even had them change the air filters. So im wondering why does the coolant look pink? 20260102_
차량 정보 없음
I have been chasing this overheating problem for a couple of months now, and I am thoroughly frustrated. The first issue was a hole in a short, S-shaped hose that goes from the the air bleed valve on the top of the water pump, to a metal line that goes back to the heater coil…I think. After this fix lasted for a month, I decided to change the thermostat…what a pain in the arse! After changing the thermostat didn’t fix the problem, I decided to flush the radiator. After starting the engine to run the flush through the engine, a broken three prong elbow connector cleat in the upper back of the e