BoostFrenzy

While i'm doing my downpipe I was checking out my O2 sensor, it has 60k on it and is quite white, wouldn't be a bad idea to replace, most cost effective/best option?

thanks

RX7Wishing

Autozone... universal sensor.. 17 bucks..

http://www.partsamerica.com/ProductD...pe=291&ptset=C

crazyrx7

Get the oem one. You won't regret it. The universal ones people had problems with them going bad. Worst case; my buddy blew his motor on a universal o2. Its your call.

R.K.

rynberg

www.oxygensensors.com -- you can get a high quality Walker sensor WITH the OEM-style wiring harness (no splicing!) for $60 shipped

Rotary Performance sells a sensor with the OEM-style harness for $40+shipping --
http://www.rx7.com/store/rx7/fdengine_maintenance.html

RX7Wishing

what? lol they are the same **** man. all it does is send a voltage signal to the ECU. Universal one you have to just splice in the old connector... 2 min job...

I HIGHLY doubt your friends motor blew because he used a universal o2 sensor.

On a side note: I have used nothing but universal o2 sensors on 4 of my cars. NEVER had any problem.. so you're call.

rynberg

What a load of crap. The ecu only looks at the o2 sensor during cruise conditions, it goes back to map lookups the instant any load is put on the engine.

You can get the OEM Denso sensor for $80 from www.oxygensensors.com, about half the price as getting it from Mazda.

BlueRex

Price an OEM O2 sensor and you'll see why everyone uses a universal O2.

BoostFrenzy

well maybe i'm barking up the wrong tree, but my fuel economy is very very poor, running good with ~8 mile short trips and staying in vacuum i average ~10-12mpg, it's pretty bad... no codes for o2 but figured it was worth a shot, is there any definate word on OEM vs. universal for cruising mileage? obviously engine health vs. o2 @ WOT is the most retarded thing i've ever heard, but for cruising i would suppose some sensors respond better than others (been my expierence in the past with universals)

Also, I notice a lot of people suggesting 3 wire (heater element) o2 sensor replacements... WHY? The car is OBD-I and doesn't listen to O2 output until closed loop water temp is met anyway, I don't see how this would yield any benefit? As hot as these things run i'm sure a non heated sensor warms up pretty damn fast regardless

DaleClark

iTrader: (55)

There's a few reasons to run a heated sensor. First, it tends to stay hotter more often so it should be less prone to fouling. Second, you can run leaded race gas on a heated sensor - a 1-wire sensor will foul out VERY quickly on leaded race gas, and a heated sensor will still foul out but will give a fairly long life.

Not sure on the FD, but on the FC the ECU would use the O2 sensor's output as soon as it was heated up and in range, even if the engine was still cold. In theory, this could help fuel economy.

Dale

crazyrx7

Hey I'm just telling you what my buddy said when he took it to a rotary specialist. He said that the o2 failed causing the motor to go. I don't know and am not going to argue either way. All I have to say is that I went oem for the simple reason that it was plug and play and made me feel at ease.

R.K.

BoostFrenzy

well not bashing any peticular shop or anything, but i'm sure a lot of things are said to a lot of customers which are a lot of complete bullshit to justify an engine/turbos replacement, but simply, the O2 has no effect on wide open throttle as it's part of the closed loop system which tries to mainstain stoich AFRs and operate all the emissions equipment in unison, floored it's using preset maps for how much fuel to how much air it sees, timing is set also (most cars will learn and yank a degree or two in knocky areas though)

However, I've had a negative opinion on "universal" o2 senosrs in the past just from feeling they didn't respond as well as the OEM and resulted in less than optimal mileage, this varies car to car though so the point of this thread was to determine which sensor would work for me and yield good fuel economy per other's expierences

RX7Wishing

I wouldnt go as far as saying that it stays "hotter". All the Heated o2 sensors do is heatup to start providing a 'more' accurate reading while the engine is cold. After the engine has warmed up and the exhuast flow is 'hot' it functions the same as a Single wire o2 sensor.

BTW: I have 19K miles on my universal as well as many runs down the track with race fuel (leaded) and have yet to experience poor gas mileage. I currently get almost 25MPG highway.

Toadman

Yeah right. The ECU would go into limp/rich mode and you'd pop a code if it catastrophically failed or shorted out. Everything said above is correct about cruise mode and fuel map reversion under load. Your friend's mechanic is FOS. Where's the shop?

And I've never had a problem with the Bosch universal sensor.

crazyrx7

I can't say where the shop is but we don't go there any more.

R.K.

PVerdieck

And the reason you don't go there anymore is???

crazyrx7

They do shotty work. The fucked up a lot of the rx7s around here. They said that they rebuild their engines with new parts but most of the engines are junk when they come out. Besides they have my buddies 3rd gen doing a 3rotor swap and have been doing it for almost 2 years. I think he is getting to the point where heads are going to start rolling. On top of that they can't tune the car with the new engine so now he has to send it out to someone that can tune it. I told him to go to pettit in the first place for something like that but he never listened.

R.K.

rynberg

Why are people afraid to name shops that suck? Especially ones that have been called out many times before...Let me guess, you are talking about a shop that starts with "H", ends with "S", and has "AYE" in the middle?

crazyrx7

No they are up here in Canada. In the same province that I'm in. I don't want to name the shop because there are probably some satisfied customers out there but for the most part there is a lot of people that won't take their business back to them. They got burnt once and don't want to get burnt again. Besides I don't want to start another flame war. Its already happened once on this forum.

R.K.