legacycentral bbs

oday i was driving my 92 Legacy and hopped on the freeway. Shorty after hitting abour 70, the temo gauge started bouncing between operating temp and all the way cold. Just drop and boucnce back. When i got off the freeway, it fell all the way and didnt move. I stopped for gas, started the car and the gauge didnt move. About 5 minutes into driving again, it started twitching and bounced up about a quarter of the way up the gauge and did this repeatedly before settling at operating temp and stayed there for my drive across town. Then at a stop light it started doing it again. I am very confused and am wondering what i need to check to figure out the cause of this

Now it isnt working at all? Any help?

thats really odd, maybe the gauge is toast now. My advice, get an autometer water temp gauge. I never trusted the stocker.

Well i bought a new sensor. It was only $35 and plan to put it in this weekend, but am thinking of a more accurate one to install when i put in my Air/fuel and boost gauges

there should be a way to test to see if the sensor is still working, its probably in the FSM's which can be downloaded. Id do that first, since it could be wiring or the gauge too.

that and the sensor doesn't send the info to the gague. there's a 1 wire sending unit right next to the sensor that sends the reading to the gague.

To make your gauge jump around like that makes me think that you had a week connection or some kind of wireing problem somewhere that finally broke. These types of sending units are usually very reliable so i'm leaning away from the sender.

wallgood358 wrote:oday i was driving my 92 Legacy and hopped on the freeway. Shorty after hitting abour 70, the temo gauge started bouncing between operating temp and all the way cold. Just drop and boucnce back. When i got off the freeway, it fell all the way and didnt move. I stopped for gas, started the car and the gauge didnt move. About 5 minutes into driving again, it started twitching and bounced up about a quarter of the way up the gauge and did this repeatedly before settling at operating temp and stayed there for my drive across town. Then at a stop light it started doing it again. I am very confused and am wondering what i need to check to figure out the cause of this

Had the exact problem on a 93 I just picked up. Changed the temp sensor ($23) and it is back to FMC. Before I changed the sensor my temp guage was acting like a boost guage most of the time, up while on the gas, down when at idle. Some times it would work normal, sometimes not at all.

Is the temp sending unit the 1 wire sensor right below the alternator? And is there a way to test the sensor with a volt meter to see if it is working?

No, it is on the back side of the engine, drivers side. brown colored plug on my car.

wallgood358 wrote:Is the temp sending unit the 1 wire sensor right below the alternator? And is there a way to test the sensor with a volt meter to see if it is working?

That's the crank sensor. You need that.

Psychoreo wrote:

wallgood358 wrote:Is the temp sending unit the 1 wire sensor right below the alternator? And is there a way to test the sensor with a volt meter to see if it is working?

That's the crank sensor. You need that.

No....that's the oil pressure sensor.

The crank sensor is a two wire sensor.

ya, sorry, brain wasn't working.

Have you changed your coolant temp sensor yet? Did it fix the problem?