temp guage could it be bad

Bad temp sender?

 

I would start with the sender, there must be some specs to compare the output of the sender when it is cold, versus hot. I would do a thread search.

 

Like he said

 

+1000

 

Hello from Germany,

I also had problems with my temperature gauge 1 year ago and started a thread. In the end I wrote down the specs of the sender. It's in the last posting of this thread:

http://www.ferrarichat.com/forum/showthread.php?t=150071

Best Regards

Martin

 

I would clean the connections at the back of the gauge as well. Mine was nice and tight when I inspected them but after I cleaned the connections all was good again. I cleaned the connections AFTER I replaced the temp sender.

 

senders either in press., temp., or even spedos seem for me to always go out just after a service: I feel wanted, and it's a priv. to see the mechanics in such a short time again.

 

I had to replace the oil temp sender on my 78 308GTS several years ago...it started reading really high, while running with normal oil pressure and water temps. New sender and all was well.

 

Temp sending unit is cheap. If I recall I paid around 30 bucks for mine from Ferrari of Silicon Valley. Henry in the parts dept. is extremely nice and helpful. I believe it arrived the day after I ordered it. It is located under the plenum. Kind of a pain to get to.

 

The guage is not electronic it is electro-mechanical (a digital guage would be electronic). As such, it has a spring or springs which may be weak or broken. There can be abnormal friction inside. Sometimes static electricity can make a guage needle stay in one position etc. etc. It may not be at all abnormal for such a guage's needle to move when the guage is rotated in a position other than its normal operating position.

 

I am ...LOL

Don't know what to tell you Mike...it could be the gauge if it's bouncing when you tap it...or the connectors need to be cleaned a little better and pinch the female connector so it fits nice and snug.

 

It certainly doesn't sound like it's broken..... perhaps inaccurate but I would want to make sure all the electrical connections from the sender unit to the guage are good/clean. Making sure the connections on the back of the guage are clean/tight is a start but I would check out the others too. I have no idea how many plastic connectors the sender wire may be going through before it reaches the instrument panel. Of course if you comparing temps. to an infrared gun then the gun should be shooting at the water temp. sender area for a more accurate comparison (might not be so easy to shoot near the sender).

I'm guessing the guage is nothing more than a 0 to 12 volt voltmeter. If you had a way to supply varying voltage between 0 and 12 volts you should see smooth movement of the needle. In theory I suppose a voltage of about 6 volts should make the meter read about halfway on the scale.

A good sign would be if your fan/fans come on at the expected temperature as shown on the guage.

 

Good call Mike...glad your running cool

 

So bad gauge and only $75 for a used replacement? Good deal, I am sure it would have cost at least that much if not more to fix your original gauge.

 

Amazing; but even new ones are not so expensive like one would expect with parts like this. Last year I bought a new one - water temp. gauge - for my car ( carb GTB, Euro centigrade gauge ). It was ~ $ 110,-- at Ferrari UK.

Best Regards from Germany

Martin