I installed an autometer phantom pyro in my truck hooked it all up correct and it will only work till about 500 degrees then drops back down to the bottom. when i slow back down and it cools off the guage comes back up to 500 and then works down from there. I've tried everything called the manufacturer they sent out another pyro and probe set, same thing again got yet another new set and same thing. have tried wiring straight to the battery to make sure that its a good ground and power and still acts the same. if i pull the probe out of the manifold and heat it up with a torch it will work fine. but as soon as the probe touches metal anywhere on the truck it doesnt work anymore........ just wondering if anyone has run into this problem or knows a possible solution

anyone???

The only thing I can think is it's too deep in the manifold. It should slide in and out until the coupler is tightened. Slide it in until it touches the other side of the manifold then back it out 3/4" or so, then tighten.

I had similar problems when I installed my EGT gauge. The problem had to do with how I wired it . I'm at a loss for remembering how I finally hooked it up. All my wiring is in a loom making it difficult to visually verify connections. Wish I could help more.

egt's initial lead coming off the probe are prone to breaking/cracking internally if bent too much.

probe is in a wide open spot..... no severe bends at all...... and plenty of clearance on the probe in the manifold when i have the probe out it will read fine when heated up but when the nut or any steel on the probe touch steel on the truck it will stop working

Mine is doing the same thing but mine won't go past 100. Where do you have your ground hooked up? I think i am going to try a different spot. It is on the drivers side in the fuse area on the two nuts that are visible there. Maybe it isn't a good enough spot for it?

Sorry i didn't read your post thuruly, I hope I , or anyone else can figure this out.

Have you called Autometer..? bet it's a bad guage.

I have all of my grounds for my pillar gauges hooked to the top stud visible by the fuse block with no problems at all.

Have you called Autometer..? bet it's a bad guage.
I had boughten my gauges off Ebay and when I got them I called Auto Meter because the harness was missing a ground wire and the pyrometer didn't light up and they sent me the wire and a brand new gauge for FREE.

Any of you Electrical experts out there have any ideas on what could be wrong?:(

I think they sent you the wrong Pyrometer honestly. I have had a set of ultra lite I's and ultra lite II's. The ultra lite II would be most like you're phantom II gauges.
I know if i tried to use the ultra lite I pyro with that gauge as soon as I grounded it it would goto 0. If i heated it up w/out touching metal with a small torch it would read correctly, until I touch it to the vehicle ground and then it went 0 again.

Sounds like the thermocouple (the probe) is bad. The junction inside is probably incorrectly welded, and as it heats up and expands, the circuit opens. Get a new probe.

Sounds like the thermocouple (the probe) is bad. The junction inside is probably incorrectly welded, and as it heats up and expands, the circuit opens. Get a new probe.
That is what i was thinking it was. Mine doesn't work at all and everthing is hooked up right ,i even switched different places for the 12v switched power and no matter what i do the gauge flickers alittle when i turn the truck on and it won't move until i turn the key to the on position again. Thanks for the advice. I will get a new probe and let you know if that was it.

Does sound like the wrong probe for the guage... I tried using a different probe with my sport comp II guage and it did about the same thing. Changed probes, now works correctly.

Does sound like the wrong probe for the guage... I tried using a different probe with my sport comp II guage and it did about the same thing. Changed probes, now works correctly.

x2 I had this happen in a buddies truck.

No performance shop around here has one of these probes. They had to order it straight from Auto Meter , it's been a week and still haven't got it , should be here on Tuesday so I will install this weekend and see if that was it.

Not to jack this thread but my (Cobalt)pyro quit working today as well. Stuck on 600 deg tried unplugging, checked all the wires, pulled out the probe and made sure it looked good. Gonna have to call autometer tomorrow.

Autometer has two probes and two gauges and they packaged the mismatched ones together for a week beforwe they noticed it. it could be that OR where did you ground your gauge? if it is anywhere in the cab the interior light switch/dimmer will affect it. I hooked my ground underneath the hood instead of in the cab and it worked fine( oh i had the same prob as you and after sending me two gauges, thanks autometer, i realized i was the moron!)

The guage has taken a dump on me. Still stuck at 700deg. Talked to tech support for 20 min. Gonna see if I can hopefully find my reciept, it not idk what im gonna do since the local place I bought it from is now no longer. Hmmmmmm

Autometer has two probes and two gauges and they packaged the mismatched ones together for a week beforwe they noticed it. it could be that OR where did you ground your gauge? if it is anywhere in the cab the interior light switch/dimmer will affect it. I hooked my ground underneath the hood instead of in the cab and it worked fine( oh i had the same prob as you and after sending me two gauges, thanks autometer, i realized i was the moron!)


Bingo! Thanks for the info. Ran a ground from both gauges to the ground strap in the engine bay and it works!!!

Bingo! Thanks for the info. Ran a ground from both gauges to the ground strap in the engine bay and it works!!!


No problem, i thought for sure the gauge would never work, youd think that would be the first question tech support asked!

No problem, i thought for sure the gauge would never work, youd think that would be the first question tech support asked!

I kinda thought it was a ground issue because i knew i had power to the gauge cause it would move every time I turned the ignition on and off.