got the turbo conversion done on my 94 eclipse and finally got it started today. Just went out for a drive to see how it ran and my other half had ecmlink up and running and he noticed that my 02 sensor wasn’t doing anything. As in flat lining (terminology is way off and I apologize). It idles at about 500 to 600, and when I let off the gas it does most of the time. It’s very... caught or laggy (however you’d like to explain the whip lash). I guess my question is, is it a bad 02 sensor causing all of these problems? My other half has an evo and told me that when he has a bad 02 sensor it barely runs and my dsm was showing the exact same problems that his did. Any feedback would help. This is my daily driver and need to get my car somewhat drive-able since my work schedule is starting to conflict with others. I’m sorry for the multiple posts and the poorly used terms. Please bare with me while I continue to try and figure everything out.

The ECM will hunt rich and lean trying to get the O2 sensor to cycle around stoich to know that the fueling in closed loop is correct.
Allot of times when O2's go bad the ECM will either end up full rich or full lean on the fuel trims since the O2 isn't cycling around stoich like it should.
You need a working O2 sensor for closed loop operation to function as intended.
Be sure you don't have any air leaks from the MAF to the intake, this will throw things depending on how bad the leak might be.
If you have a BOV it needs to be plumbed back in before the turbo inlet and not vented to atmosphere.
It really sounds like an air leak to me, even though you added a turbo the idle should be fine since airflow at idle would be the same as before.

So update: the car will run on it’s own, but will die whenever it starts getting warm. I did another datalog on my way to work after buying a new 02 sensor and there’s still no fluctuations. Someone else had the ecu before me so idk what to look for or what to change to get my car to run properly.

If you can post a log of what happening that would be helpful. How warm are we talking, like just to operating temp or...?

First things that come to mind are power transistor unit and/or coolant temp sensor.

heres the last log that i took when i had to send it to a buddy of mine

1: your TPS needs manually adjusted.
2: your O2 doesnt cycle, might want to try a known good O2.
3: coolant temp get a little higher than id like to see, but probably not a huge deal if thats the highest it gets.
4: is the car locked in open loop?

was this an actual cruise log or trying to get it to idle? when you can, post an idle log.

my bet is since your o2 is either toast, or you trul are running that lean, but i doubt it or the car would probably have had a meltdown by now. what is the rest of the car setup like, everything stock? is the turbo system using stock pieces or aftermarket? have you done a Boost Leak Test?

one thing id recommend getting asap is a wideband o2 and hook it up to the ECU for logging purposes, its crucial to ensure youre not destroying the engine, especially being an N/A-T.

well do a boost leak test tomorrow. and ill get an idle log tomorrow as well and post it here. thank you for the help i do have an aem wideband hooked up and it usually runst between 13.4-13.7. also heres all that ive done to my car: over sized hks cam gears and shafts, crower valves, low compression evo 8 pistons and rods, evo 8 maf, forced performance header, 16g turbo, um.... i think thats really it as far as i can remember. we rebuilt the motor a year ago so its hard to remember what all i did. oh and i also have 450cc injectors. and im running the mishimoto radiator and fan shrouds. i also have a 2.5 intercooler with piping.

ok so its nothing crazy.
you should wire your wideband into the ecu so you can log your AFR in ecmlink. i used the EGR input for mine, there are a couple you can use under the ECU input tab.
i also notice you are getting the same constant 3.2 degrees of knock count, as well as the knock sensor code (0031) that i was getting on my car anytime throttle is applied. i would double check the knock sensor wiring (if it is present) to ensure it i correct, did you put in a turbo harness or rewire the N/A harness for the turbo ECU? while i still havent fully solved my issue, its good to check its integrity.
your TPS is extremely out of adjustment, and in ecmlink it is set way far into compensation. this doesnt work well when the TPS is so far out, fixing that should be one of the first things you do.

id also recommend a mechanical timing check, idle set, and base timing set. that will get you a good base to start going through the rest of it.

im a MT native myself, seen a few home-state ppl join in the last week (though you joined a while ago), good to see.

Yeah we know the knock sensor is dead so I need to order a new one. Any preference?

Is there a way I can check codes that my car is throwing?

And yeah sometimes I regret living in Montana. When I need help with stuff like this there’s very few to none that do the same thing my other half and I do. But at least I’m getting the help or info I need from here. Like I said, I will do a boost leak test tomorrow, get the TPS taken care of, and get an idle log for you. I also need to fix a couple of leaks.... of course.

Oh also I did buy a turbo 1g harness

i know how it goes. honestly id still live there if there was work where i lived. but sites like this make it easier.

i try to get oem ones, but i have a couple new ones that ive gotten while trying to troubleshoot my issue.

you can check codes with ecmlink, if you go to ecu config, and then down to the DTC's tab, that will show you any current codes, and you can also clear codes from there. the knock code will probably come back since it thinks there is a wiring fault.

sounds good on the other stuff, keep at it.

so i also did a live log (with engine off) of my TPS. what i got was:
tps offset:12
tps scale 105%...
is that good or bad?

heres the log at idle. obviously i did continue the log heading to work today. the wideband showed 10 all the way into town, it died, and went to 13.5-13.7

when idling it looks like your tps is reading correctly, but the adjustment factor is way off in link. theres an adjustment procedure, should be able to search "TPS calibration" and find it, otherwise your manual setting looks good, so you dont have to mess with the sensor itself.

idk why the o2 narrowband sim is checked, might try unchecking that to see if your o2 starts working correctly. if your wideband isnt hooked into the ecu yet, it isnt helping anyway, and personally narrowband sim didnt work work for me very well.

i didnt see it die once warm, but my suspicion is the o2 is the suspect, since everything else actually looks decent.

get the wideband logging, turn off narrowband sim, calibrate tps, and a blt. thatll be a good start.

Is there a way rock search of tps calibration? I clicked through all the tabs and cpuldnt find it. I did turn off the narrowband sim

update: i went onto the ecmlink wiki page and it mentioned "simulate idle switch" when i searched for tps adjustment.

simulate idle switch is used when you dont have the physical idle switch, say with an aftermarket TB. if you have a functional idle switch on your TB, then theres no reason to simulate it with tps.

https://www.ecmtuning.com/wiki/dsmlinktpsadjustment

if you havent read through the ecmlink wiki, its a good idea if you're just learning. basically you can take the adjustments in ecmlink off, check the tps, then input any adjustments you might need.

update: got someone to tune my car since it was all sorts of messed up. he had to erase everything and basically start over. but for some reason the front 02 worked today, but stopped working when i went to drive and get a log for the tuner guy. checked wiring and everything is fine. any ideas?

Since the sensor is newer, have you pulled it to check the condition of it? Running super lean/rich can foul a new sensor pretty quick.
As for the wiring, was it actually tested? Has the wiring for the sensor been spliced at all?

ANother update: from the plug to the ecu there’s no power to the 02 plug.... stupid

At least you know now! So there's no power coming from the ECU?

There wasn’t any power but turns out a fusible relay blew for the battery. We did check the ecu to make sure there was no burn marks on it. And we changed out the relay and it fired right up