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You car probably has heated o2 sensors before then, alot of CALI and some Federal models had them depending on year etc.. so you just need to confirm you are using the right plug in the engine bay and the signal wire is going to the right spot.
You know that is the case if your o2 sensor has a 3-4 wire square connector. If you have a single wire connector you don't have heated wires from the factory and you should add those then. the other 2-3 wires are just power and ground wires depending on year of ecu.
Ali,
My car has single wire o2 sensors, with shielded wires on them. That's why I was wondering where B71 went. I'm 100% positive I am using the right wiring in the engine bay, as I had pulled the o2 sensors from the downpipe and had them dangling when I was asking about their location, etc and beeped them out. I just don't know if I should keep my o2 sensor heater wire spliced into the brown wire with white stripe and silver dots that is at B71 at the ECU like it is now, or if I should move the wire going to the o2 sensor to a different pin location, etc. I have one more 6" wire with a ECU pin at the end, so I can move it if necessary, or leave it spliced in as it is now. I saw you mention B69, didn't know if I should be moving the existing wire there or the o2 wire, or neither.
What is most likely is that there is a ground wire already going there, you would want to splice in your heater ground wire to that ground wire as it is probably already grounding something.
Sounds like you did that so you should be good, if the heater isn't turning on for the o2 sensor (power and ground wired right) you will throw an o2 heater code if your cel is working (should be working without any wiring needed).
generally that wire grounds with the key on, so there is a chance that something else in the chassis is using it.
You can actually even ground the o2 heater wire to the chassis but the ecu will not be able to control when it turns on.
I think the difference is that it will be on with the key on engine off when hardwired, but if you splice it to the ecu it will come on when its running, well that is my educated guess anyways.
I have actually been recently thinking about swapping over to the obd2 ecu again with my new turbo to see if fixed the stalling/fuel issues. The only thing is that I can't recirculate with my new intake so I figured it wasn't worth the effort. I liked it when it worked because the the JDM ecu doesn't like rev matching as much which is annoying, but hey it works.
I would really like to see someone go obd2 with a FFIM and a small efficient turbo. I didn't realize how little air my previous turbo moved on the low end.
What is most likely is that there is a ground wire already going there, you would want to splice in your heater ground wire to that ground wire as it is probably already grounding something.
Sounds like you did that so you should be good, if the heater isn't turning on for the o2 sensor (power and ground wired right) you will throw an o2 heater code if your cel is working (should be working without any wiring needed).
generally that wire grounds with the key on, so there is a chance that something else in the chassis is using it.
You can actually even ground the o2 heater wire to the chassis but the ecu will not be able to control when it turns on.
I think the difference is that it will be on with the key on engine off when hardwired, but if you splice it to the ecu it will come on when its running, well that is my educated guess anyways.
Right on man. Do nothing is a refreshing thing to hear lol.
Picked up a new battery today as mine wouldn't trickle charge this winter and was old anyway. I'll clean the terminals thoroughly and put that in along with finishing up the o2 wiring, tomorrow or Friday if I'm lucky.
Thanks again. Only a few days to go if all goes according to plan.
One more quick question. I saw with the o2 sensor wiring that one of the black wires on the denso 4 wire o2 was supposed to go to B71, and the other one goes to B+ or one of the other black/orange points in the engine bay for switched +12v. Does it matter which wire goes to which, or are they interchangeable? I've already got my chassis ground wire and signal wire sorted but don't want to make the connections on these for fear of damaging the ECU if they aren't right.
For reference, looking at the back of the o2 sensor connector (insertion side), top left is black, top right is blue, bottom left is white, and bottom right is black.
I have actually been recently thinking about swapping over to the obd2 ecu again with my new turbo to see if fixed the stalling/fuel issues. The only thing is that I can't recirculate with my new intake so I figured it wasn't worth the effort. I liked it when it worked because the the JDM ecu doesn't like rev matching as much which is annoying, but hey it works.
I would really like to see someone go obd2 with a FFIM and a small efficient turbo. I didn't realize how little air my previous turbo moved on the low end.
I never had that issue with the JDM ecu, are you using an auto or manual ecu. maybe you need to try the JDM 6 speed ecu if you can find one, I regret selling my car with one in there lol.
Originally Posted by Polarisman
One more quick question. I saw with the o2 sensor wiring that one of the black wires on the denso 4 wire o2 was supposed to go to B71, and the other one goes to B+ or one of the other black/orange points in the engine bay for switched +12v. Does it matter which wire goes to which, or are they interchangeable? I've already got my chassis ground wire and signal wire sorted but don't want to make the connections on these for fear of damaging the ECU if they aren't right.
For reference, looking at the back of the o2 sensor connector (insertion side), top left is black, top right is blue, bottom left is white, and bottom right is black.
That's the last part. Thanks!
I am pretty sure they are interchangeable that's why they are the same color on the aftermarket ones. one side 12v, the other side the heater ground on the ecu and then you wont get codes for the heater.
Sounds good, thanks! I officially finished the wiring and just need to zip tie a few things here and there to minimize rubbing. I'll take a few photos of my setup for reference for anyone curious. I wanted to turn the key and fire her up today, but I'm still waiting on all my pipes from fabrication! Sucks, but it will give me a chance to go over everything again. I debated siphoning my fuel out and doing the pump too, but I know its in my best interest to get the car running reliably first without overcomplicating things.
Pretty momentous day...I am officially 100% out of things to do but wait. I even threw the battery in and cranked it over...after only twice (about a second of cranking) it actually coughed, so I know it has fuel and spark! Everything is in place, but not detailed as who knows if it needs to come apart.
Are there any years that have egr but no electronics, only vacuum lines and the valve? I traced the harness and found the 2 connectors for the vsvs under the IM, and a third connector which I would assume would connect to the egr temp probe, but my egr valve, pipe, and vacuum hat that was basically attached have no connectors. Thinking since mine is a 92 that perhaps the wiring is there but ecu isn't programmed to "look" for an incoming temp signal, which would make things easier on my end.
Will not having vsvs connected to the 2 connectors under the IM affect anything or trip a cel? I think at this point I just need to hook up a couple evap lines for the TB and charcoal canister and I'll be set, if the vsvs are OK to bypass. There are check valves installed on all lines that originally had vsvs on them, so air can only come into the IM through them under vacuum, and boost can't pressurize anything.
A few pictures of the install...if anyone sees any glaring issues with wiring, vacuum line or sensor locations please say something!
Well, thanks to this thread, you can add me to the growing list of people with running TT ECU swaps! Once everything was hooked up to the best of my ability, she fired up after just a few cranks. Everything is still burning off, and its running open downpipe, but it runs!
The next steps are reinstalling the midpipe and tail section of the exhaust, getting a 30 degree coupler to connect the turbo outlet to the charge piping, zip tying all vacuum lines, blocking off the extra ports on the inlet tube, connecting the valve cover breather to the inlet tube, and making a cut in the charge piping to rotate it downward...the hood will hit the first catch but not fully close. D'oh!
All in all though its running great given the stuff that isn't done. I still have to set the timing and won't be moving it except in the driveway til that's done, after all these other things. Idles around 850rpm and AFR is 14.9-15.0:1, so I assume the tps is in the neighborhood. I didn't check the vacuum gauge but it would have idled higher if it had any leaks. No check engine lights after 10+ minutes of idling and some light 3-3.5k rpm revs so that's great!
I'll come back in and post up some more pics and vids once its all sorted and cleaned up.
I have since buttoned that all up besides the coupler for the compressor housing, which will be in Thursday. Still not sure what the deal is with my o2 gauge not doing much of anything, and its still blowing white smoke like a chimney...I bet my runners on my header have some residual coolant in them and its just slowly evaporating. No mixing in the oil or coolant and stuff so I'm not too worried. That and I have to rotate my midpipe slightly to seal the v bands better...not bad though!
Guys there is some questions i have that this thread dont explain ...ali sc3 here is my contact number if u can shoot me a text i have some major questions 407 590 5387
I have since buttoned that all up besides the coupler for the compressor housing, which will be in Thursday. Still not sure what the deal is with my o2 gauge not doing much of anything, and its still blowing white smoke like a chimney...I bet my runners on my header have some residual coolant in them and its just slowly evaporating. No mixing in the oil or coolant and stuff so I'm not too worried. That and I have to rotate my midpipe slightly to seal the v bands better...not bad though!
If the gauge is just sitting at 14.8 and not moving at all, chances are it isn't working. the aem gauge in particular does this, and wont move off of 14.8 until it gets a signal from the o2 sensor.
IT will start moving around once the o2 sensor is warmed up and reading right, and it should move around whether it is lean, rich , or just going back and forth between 14 and 15 (like normal when its working).
So it sounds like there is a wiring issue going on there. If you are not sure take a video of the gauge on startup and get back to me.
Originally Posted by Rm2413
Guys there is some questions i have that this thread dont explain ...ali sc3 here is my contact number if u can shoot me a text i have some major questions xxx xxx xxxx
There is a whole write up on page 1 everyone is using just fine, and if you have more questions post them in here or you can always figure it out yourself which is literally what I did before I wrote whats on page 1.
There are 3800+ posts in this thread and hundreds of people who have successfully installed this mod, yet with your first post you want me to personally contact you to answer questions this thread doesn't explain?
That is literally what this forum is for so go ahead and post it in here so everyone can help and learn from it.
Just did this on a 1992 sc300 and cant get any spark, any ideas?
Recheck your wires at the ECU. Make sure that your ECU pins are completely pushed into the connector... You must take the green clip off before pushing the pins into the connector.
05-29-19, 09:18 AM
