You're partially wrong twice, the 4 cylinder has a 'header' not 'headers' and people don't use a header for turbo, they only use them on supercharged cars. *

-Brian

(* inevitably someone will post some 'one off' application where someone is using a header on a turbo, but typically you get a turbo manifold for a turbo.)

 

*grin* ...and I'm a systems adminstrators with a strong electrical design background... it's the application of knowledge against years of accumulated experience that counts. I know plenty of people that are I.T. adminstrators in title only if you get what I mean. No offense to you, it just cracks me up when people say things like that.

The oscillation is caused because the exhaust moves past the sensor in pulses. (i.e. as the cylinders alternate firing). The stock O2 sensor has a habit of changing voltages rapidly. Wideband O2 sensors are much more stable.

Anyways, the signal does appear to be oscillating, but the oscillation frequency has no bearing on the value in itself, the value is based on voltage level only.

Standard values for this application are a little under 0.020v to 1.250v.

Actually the proper way to determine the current flow in this situation is to put a multimeter with a amperage measuring mode 'in line' on the blue wire to determine current draw. The trouble is that the resistance load is constantly changing on the sensor, so this ends up being a very crude fix unless you want to use op-amps.

Like I said, 92.3kohms. If you're making a parts run to fix this, try getting atleast a potentiometer that is 0-150kohm or 0-200kohm, and none of that PCB micropot business either because it has the potential to overheat and meltdown if the current draw is high.

-Brian

 

OMG, are you **** retentive or what, it's a figure of speech, to just headers, yes i know a 4 cyl only uses one. Don't post unless you have some input on the subject at hand. Rarely does anyone on here use proper grammar. Oh and yes it is common knowledge to get correct backpressure you need a high flo cat, and/or aftermarket "HEADER" when running a turbo or sds.

 

Hey man, don't get all pissed at me, you did post "correct me if I am wrong". If you didn't want the correction, then don't ask for it.

1st. Dispelling the backpressure myth posted by Eric Lai, a long time member of the 2G community and various DSM boards.
2nd. I never said anything about not needing a high flow cat, but my point is, you don't go out and buy a Kamikaze header and a turbo, they don't work together.

-Brian

 

First of all i'm not getting "all pissed" and second I shouldn't get corrected for punctuation, this isn't a post secondary education site, and third all I'm saying is that regardless of what you go with turbo or sds, the oem exhaust system becomes obselete. These other guys were saying that they're gonna put the stock back on and go turbo. All I was saying is that would be a waste. And I'm really not trying to start a flame war but your comments, especially to sdhotown could be construed as negative. The guy's pretty frickin smart in my opinion.

 

I'll grin with you, as there are certainly plenty of idiots in the engineering field as well. But most people seem to assume everyone else is an idiot on this board or want to know why they would have any kind of "authority"

My daily job is working on closed loop control systems and testing. So I know a few ways in and out of testing and going about things carefully.

For the record you obviously know what you are talking about so I'm not contesting you at all as you definitely have your crap together. I am somewhat notorious for going about things in far too complex a manner at times. So second opinions are great.



I was wondering/assuming the the oscillations could have been a controlled PWM type thing that the meter was picking up funny since that is what we get out of our MAF's. It wouldn't have surprised me if the computer was fiddling with the circuit taking pulsing readings, but your explanation is what I half expected and what I would also believe to be FAR more likely to be true.

I'm not sure if my meter is capable of measuring current, I just have a cheapo on hand... so I'll have to double check but yeah that is certainly the better way over estimating based off resistance/voltage drop, but it can done that way as well, just not as accurately or directly. Have to know your exact resistance etc...

I hadn't just jumped and tried the 92.3 kohms because you had said that the other person had trouble with a 100 kohm... so I'm trying to whittle my way toward your value. I suppose using a pot would work too... I'm just trying to get it so that it is right and I don't have to mess with it and soldering periodically hasn't bothered me any. But who knows. hopefully I'll get at it tomorrow morning I have parts all over the place, so no parts run, I'll just have to find the right stuff amongst my parts.

 

dropped in a 93.7 kohm resistor. Was about as close to 92.3 as I could get.. but i figured since it is only off by about 1.5% and that equates to about .003 volts assuming your 92.3 k gave you .2 V drop I figure I'll be ok. We'll see if it works or not! If not, then back to the drawing board for me I guess.

 

No go on the 93.7. Threw the error. I'll have to fiddle with it more and see what the story is.. damn it!

 

Yeah, this happened on the eclipseforums.org message board with a 100k resistor as well.

I think it may have something to do with the current handling ability of 7 resistors . (Each of my resistors is 0.4W).

You might try 3 x 330kohm resistors in parallel (86.2745kohms), or 3 x 470Kohm resistors (112kohms). Remember to use 1/2W minimum resistors when trying those values.

Good Luck!

-Brian

 

Well.. You guys certainly have put in an outstanding effort in getting the CEL to disapear w/ the kamikaze header on the Lancer. The car drove great, i felt the power, and I miss it. the bigjoshracing MIL eliminator only throws a CEL. When I removed my header from the Lancer, the CEL came back on after about 80 miles, as I didnt remove the MIL Eliminator (AKA Resitor, a few wires and some shrink tube) . After removing that sucker, it was gone. I want to put the header back on to restore the power I once had. I am still a little concerned about the car running lein/rich. I am not to savy w/ these new computer driven cars. I am a classic VW guy... I would love to go Turbo, but the price isnt worth it, I got a baby on the way... more things to worry about.. So, i figure, hell, I got another year till I have to smog that puppy... the CEL can hang around... hopefully no dammage is done... Only issue, I wont know when there is a "real" problem, if there was to be one. Again, I thank all of you for your input, minus the dude that wants to be a smart *** "no punn intended :-P" If you have any further info for me, let me know.

 

The car will not go rich or lean, so no worries. It only uses the first O2 sensor (which is before the first cat anyway) to calibrate itself to try to hit the mixtures that it wants to. So the header can't cause any damage. So enjoy and have fun with the header with no worries!

Later.

Steve

 

sdhtown..since you got the mp3...you still trying to make the mil eliminator for us?...im willing to pay for it....as long as it takes out the CEL

 

If I could have figured it out I would have very happily given it to you guys. I never was able to get one to work... and sorry but what rys is saying is not correct from an electrical standpoint. More resistors doesn't allow more "current" to actually flow. Yes it can deal with higher loads in some senses. And since we typically use 1/4 to 1/2 watt resistors.... Well at 100k P = I^2 * R which means to get to .5 watts with a 100k resistor you are talking about 22 milliamps. which is about what an O2 flows. So yes You could really use a decent sized resistor in the end... and maybe that was the problem, but i never noticed any heat or so forth... but anyway... If I get to working on the Lancer before it is sold I'll let you know.

Later.

Steve

 

Hey Guy's I just stumbled onto your board while look for info on building mil eliminators.

I was wondering if anyone has tried using polarized Capacitors rather then non-polarized? If so... do you know which direction to install them?

Thanks
Eric

 

yep I tried the polarized caps... the (-) of the cap goes to the white wire if you have the two black, one blue, one white config. Otherwise it goes to whatever is the "ground" in your config. The positive goes to the o2 signal.

Later.

Steve