I have a 94 Camaro Z28. When i first bought the car, the car was running like crap, started to "pull" a little on the highway when going on distances. IV spent months figuring out the little issues in it.
Changed: Coil, Sparkplugs (4 arc IR), Sparkplug wires, injectors, Knock sensor, TPS, MAF, MSD Cap/Rotor,and both O2s, and the ECU(to see if it would fix it)(have a 95 Z28 too)...maybe more just dont remember.

I currently "fixed" the prob, and it was running fine for a month or so, and i drive 300+ miles a week. I have been having to replace the left (when sitting in the car) O2 sencer every 2 months or so. (3 times now)What could cause this?

This is what it is doing when it starts to act up after 1-2 months after replacing theO2. It drives FINE before it starts to act up after 1-2mnths.
When driving a long distance, after a while (about an hr) I start to feel a slight "pull" or chug every 10 sec. or so. Watching the RMP it would go down about 100-200RPMs (on crouse control) when this happends and it goes back and forth. After a little while it gets bad enough to where it throws the chk eng lite. (left o2 too lean). It would only stay on for a little bit while driving (while on, car would run ok) then when the lite would shut off the car would BOG down, reducing speed, ect. and a nasty sounding sound from the engine bay when trying to go faster. Its even downshifted while on Cruse Control to try n maintain speed.It would get bad after this even in town after a while of driving. Black smoke, NO power, studdering, almost stalling at stops, etc. afterreaching OT.I could leave the "bad"O2 in, and it would continue to be screwed up. Get a replacement and it runs PREFECT for 1-2 months..then same thing again.. I actually drive 150+ miles one way on the hwy a weekend, and i have had this happen, and ALL 3 times i have parked in the EXACT same spot where it wouldnt make it up this hill. I would let the exhause/car cool for 30-45 min, start it up n run good till i get home and it acts up again.
Im sure that was all a little confuzing, but basically what im asking is what could cause the O2 to die like this, so I can replace the POS, and stop replacing the O2 so frequently. Thanks ALOT.

FYI - I DO (as of today) have a ALDL usb cable for my laptop to my OBD-1 Z28, what program would u use to maybe find out what is wrong, and the files needed to do so.

Thank you guys ALOT!!!!!!!!!!!!!!
PS: I dont have a T-Stat in, could this do it?

 

if you dont have a t-stat in wouldnt it overheat ? have you changed the pcv valve ? have you checked the air/fuel mixture ? if its running too rich or too lean it can cause the o2 sensor to go bad

 

With no T-stat it would actually run cooler. I dont think i have changed the PCV valve...once i figure out what that is ill change it . And once I hook up the cord and whatnot ill try n see if i can see the air/fuil ratio..any idea what its soposed to be at?

 

I am having the same issue as you are.
One thing that I have not checked either is the Cat have you checked yours and is it original and how many miles on it.
I would believe that if the cat was backing up it would cause the o2 sensor to go as well.
Just a thought let me know what you figure out.

 

You need a scanner or an A/F meter to check the A/F ratio, and you can also use the scanner to look at the O2 sensors. If you are using any other brand of O2 sensor other than AC Delco, you will find thatthey foul and stop working properly in a very short time. This seems to be peculiar to LT1 engines, as I never had any problems with other O2 sensor brands in different engines. Also make sure you use O2 sensor safe RTV where it can get into the exhaust stream,otherwise it will kill your O2 sensors. podsy555 also makes a good point, a clogged cat can also make the sensor overheat and fail.

As for your lap top, you would need a OBDI scanner program. The problem, because the 94 is OBDI there is little if any laptop software for it. However, for $200 to $300 you can get a decent OBDI hand held scanner. Get a scanner not a plain code reader, so you can see the actual data that the PCM is seeing.

 

ITs not a code scanner, its an all around scanner. ITs an obd-1 cable to usb. I use TTS and Free Scan. I showed a MALF 16: Lo-Res Fail aswell. All vital signes look good, other then when the car is running im showing 12.5-12.9 volts...isnt it soposed to be 14.4ish? Also, what other voltages should i be looking at? The o2s bounce all over like crazzy, so m guessing there fine. the R O2 is "slower" bu it should be fin right?

 

MAF=16, 16 grams of air per second, this is a variable that depends on throttle opening and engine speed, range is from 0 to 612. 16 is probably OK at idle, but verify it with a good running car.
Low Res signal is generated by the Optispark. This will cause the engine to run poorly or not at all.
The PCM should be able to run the engine OK if it sees 12 to 14.5 Volt