My pyrometer has a mind of it's own

[Phil Stuart]

Need some input/help here folks. I have the ISSPRO #R3607 EV gauge along with the #R658 probe and about three days ago the temps. started to swing from around 700 to 900 deg. and then back down to 750 where it usually was before just cruising at 60/65 mph. seems kinda weird,I'm talking a good 150 to 200 degree spread here for no apparent reason. I do not have any fueling box or engine mods yet and this has me stumped. I took the probe out and checked it and the wiring connections and they are OK. the connections are tight so I put it back together. I hooked up the Quick Check and drove it to work about 57 miles and nothing out of the ordinary showed up. IAT stayed at around 84 deg. and fueling rate was fairly steady. Is there something that I am missing here or should I contact ISSPRO and see what I should do?FWIW I changed out the lift pump a couple days ago at 42,000 and fuel press. is really good now. I wouldn't think this has anything to do with the pyro acting up.

Your input and suggestions are needed in this time of confusion.



Phil

 

[BigFun]

Phil,



I have the same set-up. Check your brain box and ensure you have solid connections on the + and - terminals. Ensure your - is a solid connection to the chassis ground. The Hummin' Cummins can vibrate your box pretty good. If these are okay, check all the other leads from the brain to the gauge. May be something loose there. If all is okay then contact ISSPRO or the dealer you purchased from. Your unit may very well need replaced.



Hope this helps. BF

 

[Strick-9]

I've had three thermocouple failures in the last year. One on my truck and two on the '97 nearly stock work truck.



Both failures on the '97 were as you describe. Fluctuations starting out small and growing over a few weeks to huge fluctuations 700°+ before it quits and reads 0° all the time.



good luck,



Chris

 

[azcummins]

I had the same issue with mine and it turned out that the gauge itself was dying. DIS in TX sent me a new one, no ?s asked... great guys. No problems out of my new one after a year.

 

[SlyBones]

I'm with Strick-9, had Piers test the gauge itself and it was within 50*. Then replaced the thermocouple and now its better. Was less than 1 year old. On a '97 too.

 

[Phil Stuart]

Leaning towards the probe

Mark,



I also got mine from DIS so that's who I'll be calling probably tomorrow. I seem to think it is the probe itself just the way the gauge has been reading and my driving habits. I haven't had it a year so it should be under warranty,we will see.

Thanks for the replies



Phil