Entering Closed loop faster with $A1

[tkoforpresident]

cool, so i'm good to go?

just run the 2 grounds to the ground point, the 12v wire to the junction box, and the reference signal wire into the existing sensor wire.

[robertisaar]

sounds like a plan to me.

[tkoforpresident]

Looks like my days of early morning stall-outs will be somewhat reduced


I'll get to this in a few days, I hate rushing these things

[tkoforpresident]

got the heated o2 all wired up and turned the key "on" without starting the car. After a minute the sensor body was VERY warm, almost hot.

Looks like we got it right this time

Now, that doesn't mean I'm getting a good reference signal so tomorrow or the day after I'm going to datalog to verify a good signal and then ship it off to Ben so he can play around with the closed loop timers.

[tkoforpresident]

I was afraid this was going to happen...


So i got the sensor all wired up last night and much to my dismay this afternoon I went to start the car and the battery was dead.

My thought here is that somehow I wired up the sensor to be getting power all the time so even when the car was just sitting there all night the sensor was drawing 12v from my battery.

Let me explain again how I wired it up.

The reference wire obviously got spliced to the old o2 sensor wire. I ran the two grounds to the ground point located on the passenger side fender. I ran the 12v to the "red positive" junction box just below the ground point.


But I thought that only gave power when the key was in the "on" position?

did i goof up?

Should I check my wiring one more time to make sure I have them going to the right places?

And if that checks out what can I do? Maybe we can run a toggle switch to the 12v source that I can turn on/off whenever I need to.

Or maybe there is just a better place to get the 12v from?

Please, I need help.

Any thoughts?

[robertisaar]

sure sounds like you grabbed from a constant +12V source... toggle switch would work, since it's such a low current, but kinda ghetto IMO...

you have a multimeter? or even just a test light? you should be able to find a switched +12V with either.

[pocket-rocket]

Any red wire (not to be mistaken for red w/ a tracer, which I don't believe GM uses red wires with tracers) in the engine bay is full time +12v. Does your car have a digital EGR? Those have 12+ with the ignition switch in the ON position (off with key off and people adding heated O2s use it all the time, or so I've read), as does the ICM, I believe.

[robertisaar]

took a look....

93 firebird 3.4: the EGR +12V, AIR pump +12V, CCP +12V are all hot with ignition on.

the AIR pump uses a 20 amp fuse, and i would pick that one if i had a choice.

i'm sure there are other circuits you could use, but the emissions stuff seemed easiest.

any that you know are easy that you want looked up?

[tkoforpresident]

thx for the help guys.

I don't have an air pump in my car and I don't really know where the ccp wire is located.

I just snipped my digital EGR wires because I deleted the EGR altogether.

Do you know which wire (there are 4) to tap into for the EGR?

[robertisaar]

looks like the EGR connector has 2 brown wires in it, one is the +12V, the other is the ground used to control EGR solenoid 2. you'll need to follow the wires until the 3 spilt up to go the the PCM and use the one that doesn't split, or use a test light and roll the ignition forward and see which of the two will power the light if the other lead is connected to a ground.

[tkoforpresident]

roger that. I hope I left enough wire for us to splice into.

Will update tomorrow.

[tkoforpresident]

soo here's what i did...


I ran the wire over to the fuse box and used an "add-a-fuse" to the 10 amp Ignition slot. I figured i could get my power from there since (i think) it has 12V only when the engine is ON.

Started the car up, next thing you know loud ticking (exhaust leak...) but it could also be from the crappy EGR block off plate that I made for the header (don't care if THAT leaks) and then the o2 sensor starts smoking/bubbling around the base. Maybe It's from the excess amounts of anti seize compound I put on there or maybe I didn't tighten the o2 sensor enough (prettty sure I did but I've done some dumb things before).

Then my car promptly stalled out after about 2 minutes


I can't do anything right.

first of all, is that a decent place for me to draw power from? And secondly, I'm gonna go out and see if I can tighten up that sensor some more just in case that's what was leaking.

[tkoforpresident]

ok so i tightened up the o2 sensor and started up the car (this time while datalogging). No more smoke coming from the sensor so that's good...

Interesting to note that my car went into closed loop at just about the same time it did before with a single wire o2 sensor (but we haven't changed the timers yet either)

I waited til it got into closed loop mode and then put the car in DRIVE. Couple seconds later it started idling at ~ 500 rpm and felt like it was gonna die. I quickly put it in park and gave it some gas. It idled ok for another minute. Then i put it in DRIVE again and it happened again! Dropped to 500 rpm, engine light came on, and then the motor died.

The code that was set off was 33- Map voltage High (which I *think* means that there is low vacuum) Now it can't just be a coincodence that it is acting up now after I got done with a heated o2 sensor installation and EGR! with block off plates.

Is there something I could have done to make this happen? FYI.. I blocked off the plenum with a piece of sheet metal using copper rtv as a gasket and used sheet metal, a gasket, and some copper rtv for the EGR pedestal on the header (which I think is leaking pretty bad, but that wouldn't affect the map or the vacuum would it?)


help plz

I'm such a failure

[SappySE107]

Fix the leaks before you try to diagnose other problems.

[robertisaar]

don't suppose you happen to know how John hooked up your P/N switch?

have that log where the MAP high code popped up?