"Check engine light" woes

[BennyTtj]

Hey,
I have a 1997 TJ, and the "Check engine" light has come on for the 2nd time in the last 2 weeks. The initial time, i had the codes read, and the code was for power steering, which i don't even have.
The mechanical folk say that it may be the oxygen sensor. That's possible, since it does have 71K miles on it. Any advice would be appreciated.

Ben

 

[ah_too_bad]

you dont have power steering on a 97 TJ??? Normally an O2 sensor is the culprit for all check engine lights. My fiance's car has been running with the check engine light on bc of the o2 sensor... I need to repelace it though bc it will rob you of horsepower and gas mileage.

 

[Snitty]

there is SOMETHING wrong with mine... my guesses are all shot toward the o2 sensor.. but i have no engine light.. kills me.. becuase i don't have the money to play guessing games

 

[redrooster]

Disconnect the battery cables for 15 minutes and reset the computer. If it comes back on then read the codes again. An O2 sensoe is no big deal to change. Pricey to buy though.

 

[Snitty]

yeah... changing them is really easy.. but 50-60 bucks is not for me to play guessing games.... and.. why do we NEED the 4 wire sensors.. can we use a 2 wire and forget about the heated feature... it heats up in less than a minute from exhaust anyway

 

[phatyaspen]

disconnecting the battery will not reset codes on a tj..... you need 2 have someone w/ a obd2 scanner and have them clear it

 

[phatyaspen]

also turn the ignition on of on off on and read teh number it puts on the odometer then get that number and go to the how to section and go to reference then tj comp codes or w/e(the first one)and then match up number to the problem...let us know

 

[Bounty__Hunter]

Try this:
Ignition off, push and hold the odometer reset button
Turn ignition to run (not start) and back to off
Release the odometer reset button and watch the odometer screen for a code
What did you see?

 

[jaketime81]

I am having the same problem, check engine light, loss of power, but my cat is making a rattle noise. I checked the codes and got 12 the first time, 21 the second and 55 the third. Any one have a list of what the codes mean, it does not metion it in my manual.

 

[L33TJ33P]

the Codes are listed on my Site ALL codes for the TJ

 

[Bounty__Hunter]

12* Direct battery input to PCM was disconnected within the last 50 key-on cycles.
21** Neither rich nor lean condition detected from the oxygen sensor input.
or
Oxygen sensor input voltage maintained above the normal operating range.
55* Completion of diagnostic trouble code display on the malfunction indicator lamp (check engine lamp).

 

[nkdskls1978]

Autozone can run the codes for FREE... and give you a printout... but the printouts are the same as what it says in the haynes' manuals ... go there .... I did the uplug battery trick to make the light go out... I had to get it to come back on to run the codes again though......

Dont know what to say about the power steering mix up ...

Isn't there a way to clean off the O2 sensors ... they are pricey because they aren't something that you should have to replace often...

 

[jaketime81]

Oxygen sensor input voltage maintained above the normal operating range.

That is exactly what autozone code reader said. My o2 sensor closest to the engine needs replacement. Where exactly is this located, I know there is an o2 sensor connected to the cat, but isnt that the rear one?

Is there a way to clean or repair them?

Maybe I should fix my cat (gut it) bofore I go replacing o2 sensors, but will gutting it cause check engine code problems? mmmmm. what should i do?

 

[Bounty__Hunter]

The o2 closest to the engine is on the exhaust downpipe directly below the exhaust manifold and next to the oilpan on the driver's side.

Don't gut the cat, leave it alone if it's functioning properly. Any change there will cause a fault in the 2nd o2 sensor and the jeep will run poorly and the check engine light will come on.

 

[nkdskls1978]

I gutted my cat and have had no problems with the O2 sensor.. or check eng. light comming on... It sounds louder now (sort of an echo ..Inside the cat...like an exhaust leak but its not)

 

[Bounty__Hunter]

I gutted my cat and have had no problems with the O2 sensor.. or check eng. light comming on... It sounds louder now (sort of an echo ..Inside the cat...like an exhaust leak but its not)

Do you have the second o2 sensor downstream of the converter?

 

[nkdskls1978]

Yep, I do ...and I just unhooked it yesterday because I was losing power and it smelled like gas....the light is on NOW... It jsut took about 2 weeks to be a problem...I guess i need to find out about those fake o2 sensors...

 

[Bounty__Hunter]

Check your own trouble codes.

Key off, push and hold the odometer reset button.
Turn key to run (not start) and back to off.
Release odometer reset button and watch for trouble code in odometer window.

If the guages go through thier test cycle, you did something wrong like releasing the odometer reset button too early. Post what you find.