1991 V6 Toyota Camry Check Engine Light...AND MORE!

[Estabandando]

Tonight while I was driving home my check engine light came on. It has never come on before in the time that I've owned the car (4 years). The '91 computer system isn't that complicated so it can't indicate that many things, but I don't have any of my literature to look up the potential causes. Does anybody have a list of codes for it?

A little more info that might, or might not be, related. About a month ago I noticed a drastic decrease in fuel economy along with an occasional exhaust smell in the cab. So I assumed a problem with the exhaust manifold, but the problem was sporadic and I was in the middle of moving to another state, so I didn't have time to troubleshoot. Now, just 2 weeks after reaching my new home, I fear the problem may be worsening to the point where I can't ignore it any longer. And of course, I had all the tools necessary to rebuild a car available to me at my old location, but none at my new location.

I also thought that the problem may be with the oxygen sensor, but that wouldn't explain the exhaust smell, so I'm not sure anymore.

Any thoughts...and how much it would cost to have it fixed (need to figure out if its worth it to me to go buy the tools necessary).

Thanks.

[ProMan]

Read the error code first. Your manual should have info on how to do it. Start from there.

[Estabandando]

Well the manuals suggestion when the check engine light comes on is to take it to your toyota dealer (yeah right). So I just decided to go out and buy the Haynes manual even though I already own it, but don't have it with me.

The code produced the following error:
"At normal driving speed (below 60mph and engine speed is above 1800rpm), amplitude of main oxygen sensor signal 0X1 is reduced to between .35-.70V continuously for 60 seconds or more."

Trouble areas:
- Open or short in main oxygen sensor circuit.
- Main oxygen sensor
- ECU

So I guess the oxygen sensor (or circuit) is part of my problem, but that wouldn't explain the exhaust smell. So I might have compound issues. Not to mention the oxygen sensor is an expensive part to replace only to find out it doesn't fix the problem (especially on a $1000 car). Any suggestions for how I should tackle the problem from here?

Thanks.

EDIT: I don't have any experience with the oxygen sensor...is it a part that could be cleaned and replaced with the possibility of getting a few more months out of it, or no?