Aprox. 97,000 miles on it. Engine seems fine and so does the manal transmission. About 2 months ago the SES light started coming on whenever I would be idle at a red light or something and the temperature gauge was at 3-4/16's. As soon as I'd start driving, the SES light would go off when I reached the speed of 25 - 30 mph. took it to a mechanic to fix it. He put in a new fan and tried to hook up a switch internally so that I could turn it on when the temp gauge showed it to be running hot but I told him no. After testing it with just the new fan, the SES light was still coming on. Clearing the error codes didn't stop it either. At the time, the error codes were 26, 27 (same as 26) and 53 (new spark plugs fixed that). After he worked on it a little longer, he was obviously not getting anywhere, I was told that I needed to get a new or used computer for it. Realizing that the guy was more than incompetent at this point, I left. At this point when I left, the SES was now always on and still is. I pulled the codes from it (paper clip trick) and now am getting error codes: 23 + 26. I know that 23 is a sensor and it can easily be replaced. My thinking is, by going back to when the SES light starting coming on and how and when, there's gotta be something more than replacing the computer is going to resolve. Especially since I have been more than once told that replacing the computer doesn't mean that the SES light problem will go away. Is the computer usually the first thing to be suspected? A short wire or something can't cause this?
What else could cause this? Some have told me to replace the thermostat, others say it's another sensor "somewhere". I'm at my wits end because I can't figure out what's going and how to fix it. Plus, I need to have it fixed in order to pass the inspection. It won't pass if the SES light is on. While I don't expect any answers here, I figured it would be worth a shot. Someone out there must know a thing or two about what's going on.
Sorry if I sound frustrated, but I've been bounced around a ton already with no resolution to this problem.