24Runna

Anyone know of a Denso O2 sensor that DOES NOT use the two nuts. I have a custom exhaust and they used the traditional O2 bung.

dieselloco427

I second that - just got one from Bap-Geon and it uses the 2 bolts - no good for my custom exhaust...

thook

Okay. This is an interesting tidbit of info. For atleast a couple of years now I've been trying to compile whatever arguments I can for Bosch vs Denso on the Toyotas. I've already talked to head techs at the local Toy dealer and the O'Reilly manager here about this debate. Long story short, the more info I can gather, the more I'll have to supply to said manager that he may contact the head office in regards to the chain continuing to supply "Botsched" sensors for Toyota's and hopefully try to get Denso units in stock or special order.

Here's something interesting to chew on......

If you ran a search, you'd find a lot of threads discussing this issue. I've not seen any that's mentioned this "wind band" idea, but all threads say the same things. Most have problems with Bosch units while it seems there is there is few that don't. (Maybe a determining factor is if the one's that don't have a secondary/post cat sensor.....not sure). One issue, with the 22re atleast, is the sealing flange on the Bosch unit is too large for the manifold port on early designs. But, the other debate is the length of the sensor probe. The Bosch is supposedly too short to accurately sample the exhaust. Now, I've always had problems with that theory. To prove my point, don't know if anyone here's ever noticed, but an NTK replacement (which is a Toyota recommended option in lieu of a Denso unit) has the same length and diameter of probe that a Bosch unit has. I ran an NTK for years on my '86 4rnr after I acquired it. The engine ran fine, but I almost never got 20mpg's out of it. The only time I did was with 31" tires. Go figure! But, even then, it wasn't consistant. Now I have a brand new Denso unit. The probe is atleast a 1/4" longer and large in diameter. In fact, I had to actually carve the carbon deposits out of the manifold port to even get it to fit. It's a snug one! And, now, I consistantly get an average of 20-21mpg's. The engine doesn't run any differently, though, from what I can tell. Same power and smoothness, just better fuel economy. So, I'm going to explore the "wide band/narrow band(?)" idea further. The frequency has got to be the difference.

And, of course, I suppose there would be possible differences between heated and non-heated units, but I'm really thinking not.

dieselloco427

Come to find out the wideband sensors were invented by Bosch. They are supposed to eliminate lean/rich cycling that narrow band sensors have.
Nice little Wikipedia article here: http://en.wikipedia.org/wiki/Oxygen_sensor
Edit: I did find that (at least according to internet pictures/description) the NGK/NTK have a flange that can be unscrewed and the sensor can be used with a screw-in bung fitting on the pipe. However; I can not find a parts store in my area that normally stocks these things.

thook

Ah.....nice link. Going by that, it seems "wideband" is not the issue here.

dieselloco427

Yeah. I'm not sure if the O2 sensor is even the problem in my truck anymore. It's looking more and more like the IAC (Idle Air Control). Which means new TB? I might be able to adjust the throttle stop screw to get it to idle a little higher, then re-adjust the TPS for the millionth time.

myyota

Isn`t there also an idle air control relay on your truck ?, that might be bad ?.

dieselloco427

There is an Idle Air Control - as far as I know, it's controlled by the engine temperature and an adjusting screw (which is set all of the way open) I don't think it's electrical. I'll look through my FSM tonight.