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Helz_McFugly
08-20-2009, 10:47 PM
If you dont care about your check engine light being on is it all the same to just unplug your 02 sensors?

spicerman
08-20-2009, 11:30 PM
If you read the post by Painless about computer integration,(on the main board),He has a link to an article that says that if your o2 sensor is out of range (or unplugged????) that the ECU uses a preset value that would give the engine a 14.7:1 ratio or maybe let it run on the rich side. The author of this article says that you should disconnect the o2 sensor and use fixed resistors to set the o2 signal to the computer. Thereby leaning the fuel ratio to that sweetspot that you are trying to tune to. But first you have to know what that preset value is and calculate what resistors you need. If the engine will run "unplugged" go for it!! There must be some kind of backup system to keep it running if that happens out on the road. I started my truck with the MAF unplugged and it ran fine

Helz_McFugly
08-20-2009, 11:46 PM
yea mine are unplugged. I reset the ECM and it runs fine. Ill be testing the MPG's on tomorrows trip to work and back. Ive bypassed the MAF with a resistor. I would think the only thing left to trick would be the MAP.

Helz_McFugly
08-21-2009, 05:31 PM
well I ran 100 miles today in 08 charger v6 with the 02's unplugged and resister in place of the mass air flow sensor and yielded 19mpg. back to where i started. Im thinking about buying an older car. maybe a 1980 Chevy p/u with a V6. Im not in the know enough to battle this 2008 ECM....YET!!

spicerman
08-22-2009, 10:26 AM
Couldnt you connect a volt meter to the o2 sensor and use it to see how much your hho output is effecting the engine. hook up the your meter across the sensor ground and signal wires of the sensor. You might be able to see the hho effect by a Higher Milivolt reading ???? Take a reading, then turn on the HHO and see how much it changes. that way you will see how much its effecting the engine. How much gas does your cell generate? Do you have a narrow band sensor? If you could get a MV reading with it unplugged you will know where the ECU runs in the "limp mode"

Helz_McFugly
08-22-2009, 04:49 PM
yea its a narrow band. it runs at .45 mv when idelling with no HHO on. when i kick on the HHO while its making about 1 LPM the 02 shows a mv drop to .25 to .15. I think that means its telling the ECM its running lean and dumpin more gas in. but why would it do that if they were unplugged? shouldnt it just see them as faulty and run a 14.7:1 fuel to air ratio? Ive got so many sensors on my intake manifold its crazy. I know the MAF sensor and the MAP but the other 3 that are on the air intake manifold have to be doing something to make it dump all that fuel in. ive heard of the BAR sensor. I guess i need to get a OEM book from dodge to find out what they are and what MV's range the run at and build tunable resistors for each one. or et an old beater of a car (1985 chevy P/U) that has no ECM. good oll carb and points.

spicerman
08-24-2009, 11:43 PM
Hey!...
Are you getting these readings from the sensor leads?? unplugged? across the leads?? I think low MV's mean high oxygen Witch shows that your HHo out put is having an effect. the EFIE(when hooked up) pushes the o2 sensor signal to the rich side (higher) so the ECU will cut back the fuel. So your ECU is not dumping more fuel, its only trying to maintain the fuel ratio that represents the .45Mv. And your HHO output is pushing it down to the low Mvs you are seeing. If you knew the exhaust temp. you could monitor it as you adjusted the fuel ratio lower. That would give place to the hho in the fuel mix. be careful not to burn a valve. I don't really know when that would happen but if you knew what temp. is supposed to be, and stayed within the OEM Manual values you should be ok.
I read one post under 'General discussion" The dude unplugged the o2 sensors and adjusted the fuel ratio down with a 50k pot on the MAP sensor. He was using a scan guage to set the fuel ratio. He said he was happy the way it was working, Check that out. be careful :)

Helz_McFugly
08-25-2009, 09:42 AM
yea, Im not using any type of EFIE right now. im trying to get the best one for my car and its hard to sift through all the bull s#@t trying to find one. Ill get a dual 02 efie first, I dont think i need a quad. then ill tackle the MAP and MAF sensors. and if that still doesnt work ill start looking at my other sensors to see what they are doing. any suggestions would be great.

Helz_McFugly
08-25-2009, 10:10 AM
im thinking about this for my 02 sensors.
http://tinylink.co.za/83463d

spicerman
08-25-2009, 11:08 PM
Hey .
Why would you buy an EFIE when you have your sensors unplugged??? Unless you want to put them back in the game. When you have the sensors unplugged its like having a carburetor installed. and its adjusted to give you a 14.7:1 fuel ratio (.45 Mv your seeing) Your ECU will always try to give you that ratio except when you need more power, Then it uses other sensor inputs Like throttle position (TPS), Mass air flow,(MAF) manifold pressure (MAP) and uses library tables programed into the ECU to calculate the fuel "on time" I would think that your $60 bucks would be better spent buying an OEM manual for your vehicle. Then you could find out your exhaust temp. limits and you can also find the other sensor values the computer uses and calculate the resistor you need to adjust that sensor down.(start with the MAP)

Go to the main board and see the thread on computer integration. There is a link there to a text document : OEM computer.txt Check it out before you buy an EFIE.

I have an EFIE installed on my 97 350 chev. Its the poor mans version. I can only turn it up a little or it will set of the check engine light. So EFIE's can be trouble too. dont be too quick to spend your money.

Ive been playing with water/steam injection and I've gained 2 mpg. with no changes to the system at all. I started with 10% of fuel volume and increasing from there. As long as I can see a gain I'll keep adding. But there too you need some way to cut back the fuel in order to see the gains of the HHO & water

Helz_McFugly
08-25-2009, 11:23 PM
yea i put them back in. i wanted to be able to adjust them as well as the MAP and MAF

Helz_McFugly
08-26-2009, 10:07 PM
I checked resistance on my MAF sensor today while idol. it jumped betreew 28 and 29 so I put a 29 resister in its place for now. does anyone think it will work along side unplugging my 02's and only running a efie on my map? how should a tackle this that best tricks my ECM? I jsut dont see why you would need to trick all 3 if you can get two of them to be at level outputs and just control one (ie MAP) :confused:

this 08 dodge ECM is uber smart

hhonewbie
08-26-2009, 11:15 PM
This might be what your lookin for at www.jaycar.com

spicerman
08-27-2009, 12:23 AM
Hey Mcfugly....
Did you find that text doc. that I wanted you to read???? I'm serious! Go to the main message board on this site and you will see a post called "ENGINE COMPUTER INTEGRATION" Click it. Then about half way down you will see a post called "DETAILED ENGINE COMPUTER SENSOR TUNING INFO" Click that. Then you will see a link on the first message from "painless" that says " OEM computers.txt. Click it and read the info there. Its some really good stuff!! It will help you see whats going on. then decide what to do. Good Luck!!

Helz_McFugly
08-27-2009, 12:03 PM
thanks. yea i read it. It gives a good insight on what i need to do. I think Ill go ahead and put resisters on my 02 and MAF for 14.7:1 readings so i dont get a check engine light and make something to control my BARO which i think is part of my MAP and I also want to control my Engine Coolant Temperature Sensor(ECT). I also want to get an exhaust temp gauge so i dont over do it.