Hey, I was just wondering if there is any way to test the temperature sending sensor. At least I think thats what is. Its located on the front drivers side of the engine right under the exhaust manifold. When I took it off coolant came out. The reason I asked is when I start my car and start driving and and push on the gas the temperature goes all the way up to 260, but while starting the car the guage goes up like normal. Thanks for all the help. O yea I have a 91 z28 L98 TPI.

 

it'd have to put out a signal related to temp so if you could measure it with a DVM and compare it to a known scale, or a known good part. i'd suspect something is wrong with your gauge not the sender.

 

A bad sending unit will usualy make your gage read really hot. The first time it happens you think you are over heating. There are a couple of ways you can check. After your car is good and warm grab the top coolant hose. You should be able to grab it for a few seconds. If the temp gage is reading correcly than you cannot even touch the hose. Now a more technical approach is to get your hands on a infared temp sensor. Point it at the top hose and see what it says. If it is under 200 but your gage reads 260 than you have found your problem.