Myc1972

Hello fellow Rx-7 owners!

A hazard warning has been lighting in my 1981 RX-7 GSL.
I says "OVER HEAT EXH.SYSTEM"

It seems to be intermittent. Sometimes staying on from a cold start.

What does this mean?
Where is the sensor for this?
Anymore info on this?
Is it safe for the car to be driven like this?
How do i fix it???

breesej

mine does it all the time. If you're not driving it hard and the light comes on, chances are that the sensor is going bad. This is especially true if you know for a fact that the exhaust is not clogged.

ChasRX

That happens to mine, too. I think the sensor is beneath the passenger-side floor; just above the exhaust. Although, I've yet to actually locate it!

faye x7

hmm...always just thought it was there for looks. Never heard of anyone actually seeing it go on nor ever knowing where the hell this sensor is.

Glazedham42

iTrader: (4)

About the sensor... I know there are a ton of different exhaust setups, so I'll just speak for my 85 GS here. I'm not sure about the other years. I believe the exhaust sensor is in there to tell you when the catalytic converters are getting too hot. The sensor in my 85 gs is located in the centerpipe just after the converters, near the middle of the car of the drivers side. There is a fitting on the centerpipe for the sensor to fit into and then the wiring snakes up underneath the drivers seat through a rubber grommet thing in the floor. I have removed the cats and have the RB exhaust, but the old centerpipe still has the sensor in it. I plan on removing it before I put my exhaust back on, since I eliminated all the cats. I'm not sure if it really works that well anyway....

CrazyJoe12a

Had the same problem on my '82. Light would come on intermitantly, sometimes from a cold start. My car leaks alittle when it rains, and I noticed some corrosion on the fuse panel under the dash. Took it out and cleaned everything up and haven't had the problem since.

Myc1972

So you think it is unlikely it is really overheating if it stays on from a cold start?

Lotus00

If it comes on right when you start the car then it is definatly a worn out sensor. There is no way that the exhaust would get hot enough to set it off within 30 seconds of starting the car.

Doubleohsmurf

one of my 7s is an 81, same problem on that one, my 85, and my 83; you need a replacement heat sensor. i beleive its either the sensor in the dahs or on the exhaust (been a while i cant remember too well). but dont worry the exhaust isn't overheating (not unless you're redlining it continuosly and just beatin the heck out of it driving).

85rotarypower

The sensor is under the passenger seat. You have to take out the passenger seat to get to it. Just lift up the carpet, and it should be on the floor close to the tranny tunnel. Its just held on with 2 screws. IMO, just remove it. I have NEVER seen a post asking about this sensor when its working right.

Myc1972

Thank you guys for all the information!
Sometimes it does stay on even after the car was started cold. And it will come on and go away intermittently. I never rev my car hard, and i never drive it at the red limit. I never abuse my cars. I want my RX-7 to last my lifetime!

Thank you guys for everything!

Soon i will have pics.

Doubleohsmurf

85rotarypower, i love your avatar!!!