Does O2 sensor help performance?

[jrock80]

I am trying to squeeze a little more pep out of my 90 Camry with the 3SFE. It has 132,000 on it and runs great. Doesnt stall, miss or burn a drop of oil. Most of the services on the car have been done recently. Timing belt replaced, all fluids changed, and little things repaired. Had new tires put on for winter, new wipers, all bulbs checked, a/c checked, everything electric works in the car. Even the power rear antenna. Anyway, my question is, it doesnt look like the oxygen sensor has even been replaced. I just replaced the cap, rotor, wires, and plugs. Without the a/c on I got 38MPG on a 250 mile highway trip, I was amazed. With the AC on I got 32MPG this past weekend. So the car must be running efficiently. However, if I have 4 people in the car with the a/c on, it is very very sluggish. Even with just me and the a/c on its very slow. Without the a/c is better, but still feels like it could be a bit peppier. Would a new O2 sensor help things out a little? Or should I just leave well enough alone? The car is running good, no check engine light or anything else. Exhaust has no smell to it when the car is running. Passed all emmisions tests.

[Eye8Pussies]

no, it won't make a difference....though if you had problems before, then it may

there really isn't much that you can do....jsut be happy about the gas mileage if I were you....

[jrock80]

I think I will just leave it alone. I replaced the O2 sensor in another car I had before and after that it started to have problems. Thanks for your input.

[Durrby]

I think I may need a new O2 sensor. I get around 15-16mpg even after I did a tune-up (new plugs, wires, cap, rotor, pcv valve, fuel filter, thermostat.)

[Eye8Pussies]

^ sounds like it for sure....that's some horrible mileage for a 4banger....

[ekim55121]

i blew 200 on an o2 sensor for my corolla and like a week later an explorer hit me talk about bad luck

[Durrby]

Originally Posted by Eye8Pussies

^ sounds like it for sure....that's some horrible mileage for a 4banger....

I know...I admit I don't drive like grandma but I don't feel I have a lead foot. I get around 215-230 mpt. Am I better getting a whole new O2 sensor or those generic ones where you have to splice wires? I think I might just plop down the money for the whole new unit, because I have no experience whatsoever with splicing and soldiering wires.

[Eye8Pussies]

just get a generic sensor and at least try it yourself....even if you screw up, the mileage won't get worse than you're getting now...you'll just get a cel...

but more seriously though, if you got a generic one and went to a shop to get it installed, it will still be cheaper than going to the dealer to get the oem unit

[Durrby]

So is it the front one that needs replacing, in the heat shield or the rear on? Which one affects the gas mileage? What exactly has to be done to the universal one? And what exactly goes bad with the o2 sensor? The universal ones are like $30 and the cheapest OEM one I saw was a Denso for $78

I think I might just go ahead and get the Denso one cause I don't have a soldering iron (or soldiering skills) and i'm new to the area so I don't want to spend weeks looking for a good shop to do it for me.

[PtBaller]

I need to change my o2 sensors too, where you gonna but yours from Durrby?

[Diehonda]

Precat 02 sensor regulates the air to fuel ratio coming out of your engine (affects gas mileage - Rich/Lean) Post cat 02 sensor is to make sure the catalytic converter is working properly and not heating up to much causing melt down. Once this happens it sounds like rock being shakin in a coke can.

Furthermore, universals are good sometimes, but like stated above, it may cause a CEL. Your best option is to buy a OEM replacement. RockAuto (Java based) or RockAuto

5% off discount code 277590241123 good til 10/18/05, should get a new one soon as you get one with each purchase.
* If you are using our Java Catalog, enter your discount code in the
"How did you hear about us" line of the shopping cart
* If you are using our non-Java Catalog, enter your the discount code
in the "Discount Code" field of the Shopping Cart and click "Calculate
Discount"

I have found the best deal on plugs, plug wires, and 02 sensors here.


I saw your denso for $11 dollars less than the price you posted.

[Durrby]

Originally Posted by PtBaller

I need to change my o2 sensors too, where you gonna but yours from Durrby?

I checked out a few sites and www.sparkplugs.com seemed to have the cheapest OEM (non-universal) O2 sensors. Denso, $77.48 for the front one and $54.37 for the rear. Other sites I saw had different ones for like $90+.

Originally Posted by Diehonda

Precat 02 sensor regulates the air to fuel ratio coming out of your engine (affects gas mileage - Rich/Lean) Post cat 02 sensor is to make sure the catalytic converter is working properly and not heating up to much causing melt down. Once this happens it sounds like rock being shakin in a coke can.

Furthermore, universals are good sometimes, but like stated above, it may cause a CEL. Your best option is to buy a OEM replacement. RockAuto (Java based) or RockAuto

5% off discount code 277590241123 good til 10/18/05, should get a new one soon as you get one with each purchase.
* If you are using our Java Catalog, enter your discount code in the
"How did you hear about us" line of the shopping cart
* If you are using our non-Java Catalog, enter your the discount code
in the "Discount Code" field of the Shopping Cart and click "Calculate
Discount"

I have found the best deal on plugs, plug wires, and 02 sensors here.


I saw your denso for $11 dollars less than the price you posted.

Thanks for the site, but what part number o2 sensor will I need? The only ones that I saw listed on that site cheaper then what I found were the rear ones.

[dstlaurent]

A bad o2 sensor can explain bad performance of a 3VZ-FE ???

thanks!

[jrock80]

Well I wasnt going to do it but I did. I ended up going to AutoZone and getting an OE style Bosch O2 sensor. It fit perfectly. This is not a universal unit, rather, a direct OE fit. Before the car at lights would have a rough idle, not like stalling, but a constant vibration. Now the car runs smooth as silk, it really feels like a brand new car. Acceleration seems smoother, definately do not have to give it as much gas to get it going. I learned that I have an unheated style sensor, which is supposed to be replaced every 30,000 miles. I dont think mine has ever been replaced at 135,000! Haha these cars are amazing.

[Diehonda]

Originally Posted by dstlaurent

A bad o2 sensor can explain bad performance of a 3VZ-FE ???

thanks!

An O2 sensor can make a big difference. By regulating the air to fuel ratio, if the O2 sensor is bad it can cause the mapping to run rich or extremely lean on gasoline vs air, causing the engine not to combust properly which inturn causes a rough idle, pour gas mileage, check engine light, and the exhaust will stink(smell of unburned gasoline) I am no expert bad that is what I have experienced when my O2 sensors have gone out. The precat sends the signal of air to fuel ratio coming out of your engine thru the exhaust manifold, the after cat sensor reads the air to fuel ratio in some cars but it's main purpose it to read the temperature of the gases coming out of the catalytic converter. Too hot = meltdown, which is when the catalyst starts to melt,plug, and solidify(over time) which may cause you to have to replace your muffler if you don't replace the cat fast enough. Once the catalyst melts down or solidies enoughit will break aprt and rattle around in your muffler causing damage and sounding like a coffee can with some pebbles in it being shaken like hell.

All in all, it is very important to replace your O2 sensors when the mileage or time comes, otherwise waiting too long can cause more money and time out of your pocket. A hiflo cat may go thru O2 sensors more than OEM cats. They do make O2 sensor simulators that can send the requored reading while not being hooked up to the cat or precat. Best application for that is for autocross cars running a straight thru system.