I have 82 RX-7 with 71K miles purchased new. The "Exh System Overheat" light has occasionally coming on in last 5K miles, but I don't think the cat is bad. The light sometimes goes on when the car is cold at start and sometimes goes off accompanied by spontaneous slight rise in rpm at idle. I'm thinking maybe its a switch in the emission system or the air pump. All components original. Ideas?

 

Usually it comes on when the fuel leans out and the exhaust gasses get real hot. I dunno if that could be it but I would check it out.
The air pump could be going bad as well.

 

There is a sensor after the cats in the exhaust. I just cut the wire. The light goes out.

 

I couldn't tell you. Mine was never hooked up. On the 85, it connects to the pipe between the cats and the muffler.

 

Now there is a great solution. While your at it, go ahead and cut the wire the Oxygen sensor, Coolant sensor, ect... Then you don't have to worry about any buzzing or lights going off.


-Error402

 

JWJ, your symptoms sound sorta like mine. My "overheat exhaust" light would come on at random times. My mechanic told me it's a problem in the wiring.. probably somewhere in the engine compartment. But I had the cat replaced soon after that, and interestingly enough the light hasn't come on since then.. hmm. So I don't know what to tell you.. it could be a random short in the wiring.

As for the suggestion to disconnect/cut the wire at the sensor - there are many people who have done that, actually, but if doing that works for you, I think that means your cat is bad.. and you need to get a dog.

 

Been searching the forums...is this the warning light you are talking about? If so how do you disconnect the warning sensor? Is it possible to take a picture of it? Thanks!

 

my girlfriends does the same thing, she has no airpump but still has a cat, it comes on almost as soon as she starts her fb.

 

Had to read this last post twice. Wasn't sure if he was talking about his gf or her car.

 

I had a girlfriend that had an airpump once......

 

Hahahahaha ......

 

I guess this is a better thread to post this pics. This is the location of the overheat sensor wire that I unplugged to get rid of that irritating clicking warning light. Unfortunately now the light is on all the time, but no irritating sounds.


It's on the passenger side just in front of the passenger seat


Remove the black guard and lift up the carpet


Disconnect the plug.

 

yea it is my girlfriend's fb. she has an 81 gs... i know i know shes a keeper!..