Hello,
I have an old Daihatsu Sirion 2006 with the !krfe engine and would like to clean my O2 sensor since as far as I know it was never done and the car had bad mpg
I would like to do what is shown here in the video
https://www.youtube.com/watch?v=wKOiFaNnFvU&
Which is the correct vacuum line to spray carb cleaner in my case according to the below photos?
If you need more or better quality photos let me know
I also know its better to remove and clean the sensor I have order the proper tool and still waiting
Thanks
Chris
Maybe test your AF Sensor instead of trying to clean it.
You can test them by observing the AF Sensor voltage on a scanner to see if it's operating within voltage spec and then force a "lean condition" and then force a "rich condition" to see if the AF sensor responds accordingly.
The good news is these days even the cheaper scanners can graph sensor voltages (slowly) and with a 17 year old car you really should invest in a scanner because you'll be needing one (case in point, right now).
With the engine warmed up and idling the AF sensor voltage should be around 3.3 volts (fluctuating a little from 3.25 to 3.35 volts is fine).
It looks like this when graphing the voltage:
Then, force a "lean condition" by disconnecting a vacuum line.
The AF Sensor voltage should respond by increasing closer toward 4.0 volts (in the picture it's 3.88 volts)
Like this (red arrow shows when a vacuum line was disconnected to create a lean condition):
Then reconnect the vacuum line and force a "rich condition" by spraying a little flammable liquid into the throttle body. (Carb cleaner, starting fluid, Green can CRC BRAKLEEN...whatever...).
The AF Sensor voltage should respond by decreasing closer toward 2 volts.
Like this (red arrow shows when a flammable liquid was sprayed into the throttle body to create a rich condition):
So there you go. With the help of a scanner you can test the AF Sensor without even getting your hands dirty
Seems like a solid piece of advice any good OBDII scanner you recommend that won't break the bank ?
I can't because you have a Daihatsu. We don't see those here and I don't know which scanners support them. But you can do a little research and easily find out
would like to clean my O2 sensor
do not clean O2 sensors. Test them with a diagnostic tool. If it doesn't work, and the wiring is fine, then replace it.
Which is the correct vacuum line to spray carb cleaner in my case according to the below photos?
throw away your carb cleaner. It has no place on a modern car, and especially nowhere near the intake unless you want to foul everything up.
You can use propane or water, maybe even starting fluid to test for vacuum leaks, but the most reliable way is a smoke test
https://www.youtube.com/@scottykilmer/search?query=vacuum%20leak
OK by diagnostic tool you mean an OBDII scanner or something that plugs to the O2 sensor ?
OK by diagnostic tool you mean an OBDII scanner
Yes, the 'D' in OBD stands for diagnostic.
The easiest way is just to watch your fuel trims or graph your O2 sensors at idle.
as far as I know it was never done
it's not supposed to be
the car had bad mpg
see our FAQ for ways to improve fuel economy.
Well people do clean O2 sensors with carb cleaners of by letting them soak in gas overnight. Plus O2 sensors are in the FAQ along with spark plugs and injectors
Well people do clean O2 sensors with carb cleaners of by letting them soak in gas overnight.
I have driven for over a quarter of a century and put on well past 600,000 miles amongst all my cars (combined) and never once had to clean the O2 sensors.
Well its not that you HAVE to clean them its not mandatory its just sometimes helps with your MPG
people do clean O2 sensors with carb cleaners
carb cleaner leaves a film of oil. But sure do whatever you want. Let us know how it goes.
Plus O2 sensors are in the FAQ along with spark plugs and injectors
I don't understand your point. The FAQ answers a lot of different questions and situations. But nowhere in there does it advise people to clean the O2 sensors.
O2 sensors are self cleaning for the most part. Other then that if you want to clean them you have to remove them. Spraying crab cleaner through a vacuum line is a really really bad idea. It can cause a whole host of issues. It will fully burn off in combustion chamber and won't even touch the o2. Also carb cleaner isn't ment to be used on a running engine like that. Even if you get the proper spray made for decarboning through vacuum line or intake stream it won't work on O2 sensors. None of these products are made for that.
The only thing that might work is cataclean or duralube cat cleaner. It gets added to the fuel . It all depends on condition of the sensors and there age if the product will work. If your having issues with them just replace them.
