My pyrometer has decided to play "Lets stop Chris` heart"...was cruising down the hiway the other day and caught the thing out of the corner of my eye....at 1600deg!!
Long story short it did some erratic needle sweeps for a couple of days and now the needle is buried alllllll the way past 1600, I figure if was truly running that hot I`d have a toasted engine by now but the truck runs perfect.

My question is, do the probes go bad over time or am I looking at replacing the whole gauge? I`ve already gone over all the wiring and nothings amiss.

 

What brand is it?

I had my ISSPRO tach start reading 200-500 rpm high and sent it in. They called me back and sent me a new one.

 

you should be able to test each piece and replace one part, if its like my isspro gague then its a type k thermocouple probe, a box to take the thermocouple input and convert it to some type of analog output and then the gauge. you should be able to find out what the gauge is set up to read for a signal and test that signal with a multimeter. the probe can be checked with a meter that has the temperature hookup and some type k wire.

 

I love the name Flaky Pyro

New "Flaky Performance Gauges" The number #1 source for all your racing needs!

 

its an Autometer Z series

 

Sorry, I looked up the autometer gauge instructions and see its an all in one gauge with no extra box, the isspro I have has an extra box that has to be stuffed in the dash to convert the signal.

i did read about some folks having ground issues with the gauge bouncing around with the wipers or blinkers, maybe check to ensure the ground source is still strong? also read about someone having a cracked probe too?

you can buy thermocouple wire by the foot for a few bucks at a good electical supply store. tell them type k and make sure it thermocouple wire not extension wire. just hook it to your gauge and twist the other ends together to test your gauge. it will read whatever temperature the twisted wire is touching. get a few feet and run the twist out to your hot manifold or run a lighter over it or something to see it move the gauge.

 

If it is pegged out you have a ground problem some where. That Auto Meter uses a type K thermocouple. When they go bad it goes to an open condition. That means no reading on the gage.

Start checking the grounds on the truck.

There is one by the battery on the raditor support.

There is one behind #6 valve cover.

There is one down on the raditor support near the left head light.

The dash ground is behind the OD off switch. Also check the two dash support mounting bolts. I have stripped a couple of these trucks out. Both had loose dash support mounting bolts.

 

Ok, that makes sense...funny now that you mention it, ever since its been installed it would always jump whenever I put on the headlamps. I also recently installed the matching autometer tach and it too ump when the rpm`s get over 2k...ONLY with the lights on. Looks like I have a project for the weekend!

 

Well, it was a bad ground, just not one of Mother Mopar`s grounds. The moron who installed the pyro (me) did a substandard job of grounding the pillar gauges, thats why the pyro would freak out when I turned on the lights, the lights were grounding thru the darn pyro prob,lol. works much better now....thanks to all who chimed in!