it sounds like the oxygen sensor is bad or the throttle positioning sensor or even the mass air flow sensor. take the vehicle to an auto zone parts store or a checker store and they will read the code for free and you will know for sure. most likely it is the o2 sensor
a knock sensor will retard or advance ignition spark, improving gas mileage and will not shorten engine life , if any thing it will extend engine life.
It will cause your check engine light to come on and usually you will start getting really crappy gas mileage.
the lambda sensor regulates the air and fuel mixture going into the engine. if the sensor is not accurate then the outcome is a loss in engine performance and worse gas mileage (less economical).
tell me how to replace my engine temp sensor
The coolant temperature sensor can be found on the front of the engine, near the thermostat. Remove the coolant temperature sensor retaining nut, to replace it.
replace the bad sensor and it will turn off.
You need a engine scanner and hook it up and it will tell you what sensor is bad.
Yes, replace the sensor and have the dash light reset.
I know there are at least (2) of them: BEFORE Catalyst AFTER Catalyst *Sold with or without connectors There are several brands Bosch - Denso - Replacement - SNG - Walker Products Improve Your Cars Engine Response, Gas Mileage And Lower Its Emissions When You Replace Its Tired Old Oxygen Sensor Will this really improve gas mileage? How do you know if the old one is bad, if the check engine light is not showing a problem? They recommend them at tuneups, but is this just a way to make more money?
There's no need to replace knock sensors, and there was never a 3.6 engine.
Recomended milage? uhm, usually when they break. You should have either the 3100/3400 motor, or a 3800. Both of which are non-interference motors. Unless you are getting a check engine light for a cam-shaft position sensor, keep driving it till she dies.
Make sure you are using 5W30 oil. I switched to 10W30 oil and gas mileage droped to below 20. I went back to 5W30 per owners book and mileage went back up. It could also be bad gas with water in it. I had the same problem and it turned out to be a bad temperature sensor which caused the vehicle to run rich. Gas mileage improved after the temperature sensor was replaced. How is your heater working? Not so hot? May need to replace the engine coolant thermostat.