Help..Car Sputters over 2rpms??

[lexdiamonds]

I have a 99 Protege automatic, its a base model with the hub caps and minimums. The car all of a sudden sputters if i go over 2 rpms? Its sorta of like it have to drive slow and slowly accelerate. If i try to just drive normal from a stand still, it feels like its going to stall and jerk. Its almost like it wont go over 2rpms or almost 2. Any ideas? Maybe spark plugs?

[smokstac]

Had a very similar issue with my 97 and it turned out to be a bad primary O2 sensor (the one in the exhaust manifold). Didn't throw any codes but it was sluggish, wanted to stall if you opened up the throttle, took forever to reach 35MPH.

[lexdiamonds]

Thanks, how much do you think an 02 sensors is and is it easy to install?

[smokstac]

O2 sensors are generally easy to install if they are the ones on the manifold...usually you just remove the heat shield (if it's there) and use a special O2 sensor socket to remove/install the sensor (the socket is long and has a special cut out on the side to allow the wire harness to come through).

Only major challenge with this (usually) is if the threads have welded between the sensor and the manifold...this could result in needing a new manifold if the threads get damaged enough while removing the old sensor.

Sensors vary in price...I think the upstream sensor is around $60 new from Rockauto.com. The tough thing is that when mine went bad there was no "check engine light" on nor any OBDII codes stored....it was random luck that I came across the solution myself.

The primary sensor is very important as the engine's computer uses it to determine how much fuel is needed to keep the engine running.

[lexdiamonds]

Thanks man, I really appreciate all the info, I'll keep u posted on my progress.

[1Mazda323Fan]

Spray the old sensor down with PB Blaster or something similar and let it soak for a bit before you try to replace it. It should help loosen it up and make it easier to remove. Also, you can probably find a combination wrench which will fit on the sensor if you don't have an O2 sensor socket.