temp gauge problem 86 cpe.
Thread Starter
Cruising
Joined: Aug 2001
Posts: 12
Likes: 0
From: Westborough Ma.
temp gauge problem 86 cpe.
my 86 cpe temp gauge driving me crazy, i bought it a couple of months ago
to use as a driver, that i could jump in as an alternative to my 37 chevprostreet.
i've spent more time chasing electrical and other problems on the corvette.
when i start the car(cold) my digital temp gauge will go up to 299 as soon as i step on the gas, but will come back down when i let off the gas. when i stop
at a lite it will jump right up to 299. the car is not running hot, i have never overheated. first part i replaced was the temp switch on pass. side head, no change. i knew i needed a gauge cluster when i bought the car so i replaced it with a rebuilt one , that took care of my LED problems but the temp gauge
still has the same problem. i also tried a new computer, no change. also the
lites on the temp/volt gauge in the cluster are not as bright as the rest of the
cluster. my next thought was a bad ground but not sure. any ideas out there?
to use as a driver, that i could jump in as an alternative to my 37 chevprostreet.
i've spent more time chasing electrical and other problems on the corvette.
when i start the car(cold) my digital temp gauge will go up to 299 as soon as i step on the gas, but will come back down when i let off the gas. when i stop
at a lite it will jump right up to 299. the car is not running hot, i have never overheated. first part i replaced was the temp switch on pass. side head, no change. i knew i needed a gauge cluster when i bought the car so i replaced it with a rebuilt one , that took care of my LED problems but the temp gauge
still has the same problem. i also tried a new computer, no change. also the
lites on the temp/volt gauge in the cluster are not as bright as the rest of the
cluster. my next thought was a bad ground but not sure. any ideas out there?
Burning Brakes
Joined: Sep 2000
Posts: 1,199
Likes: 1
From: NewCastle IN. USA
Re: temp gauge problem 86 cpe. (paul 86cpe)
you might try checking the wire going to the temp switch. it has a sheetmetal bracket that is crimped around the wire (don't ask me why they did it) and bolted to the block. maybe its grounding out? If it needs fixed I'd forget about the sheetmetal bracket, its way to hard to get off the wire. just splice in a new wire and cover it with some abrasive tape (looks like electrical tape but rough and you have to cut it) some hardware stores have it.
RJ
RJ
- 1986 Original Owner -
Joined: Apr 1999
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From: North Yorkshire, England
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Re: temp gauge problem 86 cpe. (paul 86cpe)
Paul,
The item you replaced in the passenger side head is a sensor and not a switch. A switch (like the one in the driver side head on '86s with B4P) will be open or closed, the sensor will have a variable resistance, in this case based on temperature. I just wanted to make that clear, so we are all calling things what they actually are. The guage will read LO if the wire is disconnected (which would be high resistnace from the sensor on a cold engine) and 299 if shorted to ground. I believe you may have some melted insulation on the wire going to the sensor you replaced. As close to the exhaust manifold as it is, it's likely. This melted insulation would bare some wire and it could be touching something on the engine and shorting when you hit the gas or brake, causing the guage to read 299. Have a good look at the wire coming out of the harness up to the connector that plugs into the sensor to see if there has been any heat damage.
The item you replaced in the passenger side head is a sensor and not a switch. A switch (like the one in the driver side head on '86s with B4P) will be open or closed, the sensor will have a variable resistance, in this case based on temperature. I just wanted to make that clear, so we are all calling things what they actually are. The guage will read LO if the wire is disconnected (which would be high resistnace from the sensor on a cold engine) and 299 if shorted to ground. I believe you may have some melted insulation on the wire going to the sensor you replaced. As close to the exhaust manifold as it is, it's likely. This melted insulation would bare some wire and it could be touching something on the engine and shorting when you hit the gas or brake, causing the guage to read 299. Have a good look at the wire coming out of the harness up to the connector that plugs into the sensor to see if there has been any heat damage.
Thread Starter
Cruising
Joined: Aug 2001
Posts: 12
Likes: 0
From: Westborough Ma.
Re: temp gauge problem 86 cpe. (paul 86cpe)
thanks for your help, the problem was a bare wire about eight inches from the harness on the drivers running to the temp sensor, must have touched the manifold.
