EGT guage not reading correctly?

charliebean · 11-22-2006, 10:52 PM

Just installed a set of guages in my 2007 Classic (Boost & EGT) the pyrometer doesn't seem to be reading right. When the engine is cold after sitting overnight the guage will read 250 degrees. Is this normal? cruising at 70 MPH with about 3.5 to 4 lb.s of boost it reads about 350 to 375 degrees. Is this about normal? And when I accelarate past 3/4 throttle it buries the guage (past 1600 degrees) I have the Superchip Flashpaq installed on tow performance with a 4" turbo back from MBRP. Do you think that i have a defective pyrometer? Thanks in advance for any help

**Tow Master** · 11-23-2006, 12:24 AM

Not trying to sway your topic but.... How hard where they to put in? I never done them before and I'm looking into it.

Id get a heat gun and see how hot the manifold gets. It could always be a sensor.

charliebean · 11-23-2006, 02:08 AM

They were not that hard to install. The hardest part was getting the intercooler tube off of the intake to remove the shaving from tapping the intake. The guages are mechanical not electric.

**05_LLY** · 11-23-2006, 06:38 AM

Sounds like a bad probe, but its really hard to tell its one of those things i would just send the whole deal back, or call the place you bought it and see what they want to do about it. THe idle egts are just about right mine idles about 250 275 all the time but i can bearly hit 1500 with a 460rwhp tune loaded!!

Tow Master

If you decide to do gauges let me know i'll give ya a hand, i even have a warm garage if needed

. But if your interested i also have a lbz egr blocker and fingerstick i got stuck with if you want it!!

charliebean · 11-23-2006, 03:42 PM

The 250 is not at idle, that is what it shows before I start it. I guess I will have to send it back.

**05_LLY** · 11-23-2006, 05:04 PM

Opps, yeah mine reads 0 when off usually jumps around while starting the truck then idles areoun 250 275 unless in the summer with the ac on it can get to 350 at idle!!

I would try to get the gauge replaced for sure!!

duramaxdavid · 11-23-2006, 07:44 PM

Boost soubds about right but the pyro seems off. Id also return it.

rebel7777 · 11-24-2006, 06:14 AM

Before returning the gauge, I would check that my wiring is correct. With a J/K type thermocouple they only put out a mV signal and are +/- sensitive. You can even download off the web a J/K vs mV chart to correlate back to what you should be seeing on the 2 wires off the probe. You will need a DVM (Digital Volt Meter than reads mV) to do this. As well any improper connections will drop or impede the mV from registering properly on the gauge. A thermocouple is made up of 2 dis-similar metals that are welded together at the tip, which when connected will produce a mV output. Usually when they fail they fail high or Low, not usually in between.

charliebean · 11-24-2006, 03:30 PM

Quote:

Originally Posted by rebel7777

Before returning the gauge, I would check that my wiring is correct. With a J/K type thermocouple they only put out a mV signal and are +/- sensitive. You can even download off the web a J/K vs mV chart to correlate back to what you should be seeing on the 2 wires off the probe. You will need a DVM (Digital Volt Meter than reads mV) to do this. As well any improper connections will drop or impede the mV from registering properly on the gauge. A thermocouple is made up of 2 dis-similar metals that are welded together at the tip, which when connected will produce a mV output. Usually when they fail they fail high or Low, not usually in between.

Thanks I will look into that