Does anyone know the correct, (not positive I'm wording this right) ohms, resistant, volts, watts, all those specs for the rear O2 sensor on 98 t100 3.4L 4x4 with automatic transmission? I'm trying to go buy a resistor and capacitor thing from a gadget store. Again I know I'm prob not wording this all right, I would just like to know the all specs.
98 t100 O2 sensor
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Yo, I know you said between 10 and 20 ohms at .45v.... I live in a very residential area on beach pretty much hidden. One gas station and a dollar general that's it. Everything else a hour away. I know I could order the resistor online and plan on it, but I was given a 60 ohms resistor... Would that hurt the truck? Chock it make it run too lean perhaps?
There is no cat, no rear O2, no pipe, no muffler. Seen alot of people putting a ohms resistor wired up to where rear O2 sensor goes just to keep the ECU from not freaking out. I cant put a rear O2 sensor without a cat. But running it the way I am there is no signal so it is burning extremely rich. Can't put a pipe or anything on it because the front O2 sensor sees pressure and calls for so much fuel and air it blows every pipe off it. It doesnt make any sense
Well you can order a lower resistor or wire the 60 in and run it? Not sure what the voltage drop will be but it's gonna most likely throw a o2 code but I doubt it would cause any damage as a short run test. If it's too lean it should be notice-able in how it runs and the knock sensor might throw a code if the ecm can't compensate.
You've got a odd one there. I haven't heard of the resistor trick before but most vehicles still have an exhaust system and just a bad cat or sensor.
You've got a odd one there. I haven't heard of the resistor trick before but most vehicles still have an exhaust system and just a bad cat or sensor.
Really man I can't figure it out. I've talked to a lot of people that know what they are talking about, including you a few times and everyone is left scratching their heads. I do HVAC and understand a lot about air flow and I just do not get how it ran stock with cat and muffler fine. I remove it all the way to the first O2 sensor runs fine. But runs rich as hell and loud af. I put a straight pipe on it with a bigger I.D. no cat no rear sensor, no muffler and it builds so much pressure it explodes it off. I'm not going to spend money on this old farm truck buying a cat, so I was just going to try to trick the ECU to make it burn more lean and pipe it to make a little quiet. Idc about check engine light or none of the other stuff.
What happened to your old converter? 
I know you don't want to put in a converter but it might be yer only choice at this point to keep yer engine from running so rich. Are you sure the MAF isn't dirty? Probably wouldn't hurt to give it a good cleaning. Using an OBDII scanner, what are yer MAF readings at idle?
Here's the cheapest converter I've been able to find fer the 4WD T-100. About $160 shipped from eBay.
I know you don't want to put in a converter but it might be yer only choice at this point to keep yer engine from running so rich. Are you sure the MAF isn't dirty? Probably wouldn't hurt to give it a good cleaning. Using an OBDII scanner, what are yer MAF readings at idle?
Here's the cheapest converter I've been able to find fer the 4WD T-100. About $160 shipped from eBay.
1995 1996 1997 1998 TOYOTA T100 3.4L 4WD Catalytic Converter | eBay
1995 TOYOTA T100 V6 3.4L. 1995 TOYOTA T100 DLX V6 3.4L. 1995 TOYOTA T100 DLX EXC V6 3.4L. 1995 TOYOTA T100 ONE-TON DLX V6 3.4L. 1995 TOYOTA T100 SR5 V6 3.4L. 1996 TOYOTA T100 V6 3.4L. 1996 TOYOTA T100 SR5 V6 3.4L.
www.ebay.com
The thing is a complete rust bucket that was given to me. And 2 very good mechanics couldn't get it to run so off a bet I said if I get it running hand me the title. It sat under salt water for a long time after hurricane Micheal . The exhaust was 100% holes falling apart, and the engine acted like it was choking so I just cut it all out.and I didn't care if it had no exhaust, but I didn't anticipate how loud the thing is.... And then realized how rich it's burning. So I just wanted to straight pipe it with pipe in the yard make it a tiny bit quieter, and maybe hold some back pressure to not burn so rich. But without the rear O2 when I pipe it, the front one seems to freak out and call for so much fuel and air it has exploded 4 pipes off it. And the engine light starts to blink when I pipe it.
It's possible that the ECU may be damaged. You might want to pull the covers off and see if any traces are eaten away. You could even find a used one that might resolve yer issues. What are yer fuel trims when the engine is running without the pipes? Have you noticed any wiring harness issues? Probably wouldn't hurt to inspect the ECU wiring harness connectors fer any corrosion.
ECU looks good. And I've followed many wires ( I damn sure won't claim I'm followed every wire on this truck) but I have many times followed wires doing this and that and every harness I come to I stop (usually) what I'm doing and unplug it spray electric cleaner in them and plug back up. ECU looks just fine. Besides if it was damaged wouldnt it act up all the time? How in the world would a damaged ECU ONLY act up when I put 6 feet of straight pipe on it with a bigger id, no cat no muff. I simply just extended the pipe just past first O2 sensor.... And also I have no idea what fuel trim is..
It's the readings that the ECU is encountering with the flow. The MAF could be reading it correctly and the ECU could be interpreting it incorrectly. There's a lot of variables to account fer. If you had another ECU to work with, it could give you a start in the right direction to look.
BTW, what are yer readings with the OBDII scanner hooked up?
BTW, what are yer readings with the OBDII scanner hooked up?
I mean it's possible, but if something is reading incorrectly, wouldn't it read in correctly all the time? How or why or what would make a truck running perfectly fine rn with the no nothing at all just past first O2 sensor. Engine light is on but doesn't blink. Trucks runs great, to simply putting 6 feet of straight pipe on it and all of a sudden I can't make it 100 yards and truck buitl so much pressure it blows the pipe off and the engine light starts flashing the moment I pipe it and fire it up, and then after the truck had blown the pipe off, engine light doesn't flash and runs just fine again....???? And I haven't hooked up a scanner to it recently so idk. I guess I'm going to have to get one, pipe the damn thing and drive it makimg the engine light flash and see what the hell it's throwing
The flashing is an indication that there are misfires being detected. It is not recommended to run the engine in this condition as it can damage it.
I'm curious on the O2 sensor reading as well as the MAF reading. The front O2 is what the ECU will use to calculate the fuel mixture along with the MAF and engine coolant temp (ECT) sensors.
I'm curious on the O2 sensor reading as well as the MAF reading. The front O2 is what the ECU will use to calculate the fuel mixture along with the MAF and engine coolant temp (ECT) sensors.
I fixed all misfiring from the beginning, also before I fixed them, check engine flashed everytime I cranked it and drove first 2 to 3 miles which is what it should do. Once fixed it never flashed again. Still doesn't. Now if I put pipe on it, flashes, pipe comes off, it never flashes again. Not once. Never. I know flashing means misfire, but why is it calling a misfire only when I put a piece of pipe on it?
Saw posta on Tacoma World with guys attempting to run straight pipes on the 3.4 and 4.0 V6.
All had major issues due to their trucks running super rich. The only guys that succeeded were the ones who left the cat in place and straight piped back from there.
One bought a URD Racing MAF and had them dial it in before putting it on the truck. Expensive experiment. They gave up and went back to stock. I doubt you'll be able to get it with-in range for the front A/F O2 sensor and ECM to lean it out.
I think? the blow off of your exhaust is un-burnt fuel that ignites in the pipe and can't exit fast enough.
All had major issues due to their trucks running super rich. The only guys that succeeded were the ones who left the cat in place and straight piped back from there.
One bought a URD Racing MAF and had them dial it in before putting it on the truck. Expensive experiment. They gave up and went back to stock. I doubt you'll be able to get it with-in range for the front A/F O2 sensor and ECM to lean it out.
I think? the blow off of your exhaust is un-burnt fuel that ignites in the pipe and can't exit fast enough.
Ok now that's the first theory that actually makes some sense. Removing cat and rear O2, front O2 is calling for so much A/F the only reason it's successful is because it shoots straight out right past first O2, with it burning so rich it dumps fuel and when piped it can't get out. Now that makes alot of sense.
Ok what do you think about this, number one goal is to make the damn thing quieter, even if it's just a tad. Second it would be nice to run leaner, what do you think about a simulator for rear O2, or I have seen many put just a ohms resistor on rear and left outside the pipe.
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