FWIW, our rigs ECMs only read/support narrowbands... Could be part of your problem. Not sure if the voltage comes from the the wires to it, or if the 02 sensor itself regulates output voltage from input current...

 

RSR,

reading back I found the link posted by RJR, and on page 14 it talks about the test tha tI have been using to get these voltages.

http://www.autoshop101.com/forms/h27.pdf

It seems that the voltages I am reporting make sense with the autoshop manual. Also, the heated oxygen sensor page in the FSM suggest I could be readingup to 5 volts from the VF1 and E1 terminal as well.
http://personal.utulsa.edu/~nathan-b...01heatedox.pdf

 

Cool.
Have you checked your electrical system for dirty AC volts?

 

You know, the idea has been suggested and I thought there is a good possibility that dirty signals are causing some of the issues. Although right now I am still testing various aspects of the system. Currently I've adjusted the AFM further and am still on the first tank of gas so I don't know what hte MPG difference is, but I've certainly seen the voltage from the O2 sensor go from a steady 1 volt to about 1.9 volts. However, that signal itself is also not very clean.

My friend has an oscilloscope which we will use soon to see the cleanliness of the various signals.

I'm still trying to find the answer to why the ECU isn't adjusting for the slightly rich condition if the signal is getting to it correctly. At the moment I am assuming the ecu is at its limit in the leaning out direction... I have further tests in mind that I will post later to see if it makes sense to everybody, and then I'll do the test...

It's a process

 

You are running aftermarket injectors right? One pair runs about 8% richer (could be more) than the other.

I also think there's a sensor giving a poor reading. It only takes one to ruin the whole thing.

 

Gamfreak, i am running the orange flamethrowers, same as yours I believe. They should be the same flow rate. Although some places on the internet people believe it is about 3 % higher flow rate than stock.

 

I think it's a bit of a misconception that the ECU can "learn" and adjust to anything you throw at it in terms of injector sizes, air flow, etc. According to the Autoshop 101 articles, the range of adjustment is limited to about +/-20%. If you think about it, this is a requirement for "limp-home" mode. Otherwise a defective sensor could cause the ECU to keep adjusting mixture and timing off into the weeds until the engine either quit entirely or suffered damage.

I'm pretty sure that feedback voltage you read on VF1 with TE1 and TE2 open is really telling you how much of that +/-20% the ECU has used up. Once it hits +5V or 0V, it's done all it can do. It's up to you to give it some help to get centered back up.

 

The seller demonstrated on his website that the silver ones (the cheaper ones that I run, not much cheaper now though!) flow at 8% more than stock (measured in cc's). He used the testing equipment to show it. My MPG's went down when I installed for this very reason. Leaning out the AFM is a must if you want that perfect ratio, but in most cases the ECU will adjust. If you have the silver ones, it's running rich but it's to be expected.


The orange ones (more expensive) seem to match stock flow rates.

 

RJR,

I understand and agree with your statement. I was thinking that I will test this after I make sure my sensors and wiring is all good and not causing any issues. Which will then leave the fuel and air mixture the only thing to adjust. I am thinking for a test to see where in the ECu's range the engine is in right now, I would lean out the AFM incrementally and log the O2 sensor reading. Once I have adjusted and logged up to the point where the engine is now running lean continuously, I would then know that I have reached the other limit of the ecu's 20% range. What I should see in the results then is a steady increase in voltage from O2 sensor up to 2.5 volts, then a no change for a few increment adjustments (towards lean still) then it should start to increase again. If this is the case, then I can assume that my current setup where I'm running an avg 1.9 volts was outside of that limit wherein I am significantly rich.

I have been thinking a lot. I don't know if it will come to this.... and I'm looking forward to your program

 

I am running the orange ones. I got them specifically so I don't have to change fuel ratio. lol.

I have yet a few things to test before I conclude the injectors are flowing at a higher rate though.

I just can't help but to discuss everything on here

 

That makes me think it's a sensor. I've replaced every fuel/coolant related sensor on my engine and that's because ALL of them failed at one point or another. Some are dirt cheap like the ECT, so it really can't hurt if you have the original ones in there.

 

Yessir. I am going to put the order in today. Dang work is in the way .. so much for 'resistance' testing these things

I am dreading another plenum removal though. Perhaps I am patient enough to get to all of them without touching the plenum.

 

Btw, the program is on line. See the thread "OBD 1 Diag Port Reader" elsewhere on this forum.

Ron

 

Great! I will check it out

 

Guys, I need some help. Im mostly colorblind so the few pics I found arent clear enough for me. I remembered when wiring up my new ECT cinnector I wasnt 100% sure which wire goes on which side of the connector. So I was thinking the ECT sensor is good, but it could still be that I wired it backwards so its sending silly data to ecu. So to test I crossed the wires thinking if I got engine code then it was right. But I crossed and no codes.so Now I need to be sure which color wire is on which side of the connector. If someone can chime in my wife isnt gonna be around for a while to help with colors in pictures

 

I found a picture. Can someone confirm which side is which color? Thanks!!!http://api.viglink.com/api/click?format=go&jsonp=vglnk_jsonp_13953683684168&k ey=a5e11b5075b509bfc2570af7b6e5b404&loc=http%3A%2F %2Fm.yotatech.com%2Fshowthread.php%3Ft%3D269091%26 page%3D2&v=1&libId=4f500f73-54f1-4e5b-aa8b-760e0ddebdad&out=http%3A%2F%2Fs1364.photobucket.co m%2Fuser%2FChristopher_David_Burch%2Fmedia%2FIMAG1 370_zpsbe636920.jpg.html&title=Christopher%20D%20B urch%201989%20Pickup%20Build-Up%20Thread%20-%20Page%202%20-%20YotaTech%20Forums&txt=

 

It won't really make any difference. The ECT sensor is just a temperature sensitive resistor, so polarity doesn't matter. The wiring diagram, however, shows green going to pin 4 of the ECU and the brown-black going to the common ground point.

 

Ron, the wiring diagram doesnt help here. I got the connector without wires so I dont know which color wire goes on which side of the connector. I guessed it would be an issue, but you are saying it wont matter.. interesting. I guess Id still like to get it right so Im not thinking about it anymore Also my wife got home early and helped me with that picture. In fact I did have it backwards

Anyway... I also pulled my plugs today to see if they look the same. They do, mostly, on 1 and 2 there was a good amount of fresh fuel odor. The others looked very similar and no noticeable fuel odor. I did run the cold engine for just a few minutes before pulling plugs. And I still dont have my CSI connected.

Still working on finding a cause, if one exists other than new injectors, fot engine running rich. The plugs didnt show any signs of extra heat, another Tank of fuel and I may adjust afm again.

 

Ron,

you were right, the wiring being backwards didn't change anything after I fixed it on the ect sensor.

I still got 14 mpg on my last tank of fuel, after I adjusted the AFM lean 3 more clicks.


Below are what the plugs look like. The Voltmeter(TE1 not connected) is still steady at 1.9 volts under moderate acceleration and about 1.2 volts steady state. The plugs seem to indicate slightly rich...??? I mean they don't look bad at all.





This one is cylinder two, and same as cyl. one, it had a fuel odor.

 

Well guys, I adjusted the AFm again. Leaned it out to a total of 12 clicks. This is the video of the new readings with the TE1 port NOT connected. Clearly it is different than before. I'll put this on a chart soon, been extremely busy lately. To recap very quickly on the results: AFM at stock setting I was getting a high voltage reading (at steady acceleration) of 0.5 volts, at 4 clicks lean the voltage was 1.5, at 7 clicks lean it was 1.9 and now at 12 clicks lean it is 2.7 volts. So there is a clear indication between the AFM setting and the O2 sensor readings. Between the stock configuration and the 7 clicks lean the MPG had not changed. I have been getting a steady 14 mpg thus far. I haven't been through a whole tank of gas yet on the 12 clicks lean setting, I hope I get better mileage. As Gamefreak mentioned before, I also think one sensor is sending incorrect information causing the Engine to run rich. I checked my plugs throughout these AFM setting changes and they seem to be indicating the trend towards the leaner condition as I adjust the AFM lean, so all of that is making sense. Currently I am putting together RJR's OBD diag program hardware to see what the sensor data is that the ECU is seeing, and hopefully that sheds some light on what is causing the rich condition issue. I don't like the idea of running 12 clicks lean on the AFM tricking the computer to run properly when it should be able to do it on it's own. The orange flamethrower injectors have the same volume flow as the stock, so assuming they are working properly, so it shouldn't be my issue. Meanwhile, I'll be taking her out to the mountains for the first time... we'll see how that goes

On the new video, as before, the voltage under light acceleration goes to about 2.6 or 2.7, when I back off on the throttle a little bit to maintain speed, the voltage drops to about 2 and stays there steady. The problem is, during idle, or no advance on the throttle, the voltage goes to 0 for a sec, then moves back up to about 2 volts or so and stays there. I thought during idling it should drop to 0 and stay there? My TPS is adjusted correctly and it is for sure in idl circuit when it's supposed to be. As long as the car is usable, this is kind of fun