EGT at Idle

[cwsoules]

I have been told to idle my truck until the EGT drops to 300 degrees. When using my truck to run errands the EGT comes down to 300 very quickly. Today I carried about a 1000 lb load home at 65 mph for much of the trip. After driving about 20 minutes I reached home and let my truck idle. The EGT came down to 400 degrees within a few minutes, but did not come down further. The truck idled for over 20 m inutes at 400 degrees and did not cool any further. The transmission was in park.



Any ideas? My EGT gage is a new Banks which has been in the truck for about 6 weeks.

 

[Bob Wagner]

that's odd

make sure that you shift into park or neutral.

 

[CumminsAholic]

Usually when I drive my truck and I get back it'll cool right to 400, then to 350 in another minute, but doesn't go much below that, at least not in the amount of time that I've waited. I just make sure it's under 400 before I shut it off, usually 350. The cooler the better, but as long as it's not really high I don't think it's going to make a huge difference. Look at the older trucks with 300k, I bet they didn't always wait to shut it off.

Corey

 

[LSMITH]

If you have the defrosters on or the A/C it will not cool down in my experiences. Turn the climate control off or to a vent setting and try it again. That is my best guess, hope it helps.

 

[Michael Hughes]

Make sure you don't have your exhaust brake on.

 

[Bob Wagner]

I usually leave the defrost on everyday and its never been a problem

 

[WestTN]

Have you checked to see that your Pac Brake isn't sticking partially closed?

 

[DRR-24V]

PacBrake?

Maybe you left the PacBrake on. It will not drop to 300 with it on.

 

[Steve St.Laurent]

I agree with Howard, make sure you the HVAC controls in a position where the A/C compressor is not on. There are only three positions that have the compressor off - the vent position, the lower vent position, and off. Bi Level and all the others run the compressor. I have a turbo temp monitor on my truck and it shuts itself down when post turbo EGT's get to 300 degrees. If the compressor is on it takes WAY longer to cool to 300 degrees (multiple minutes sometimes). I always turn it off a few minutes before I stop.

 

[hammong]

Agreed!



My truck WON'T make it below 300 degrees if the A/C compressor is running (eg: defroster). I also make it a habit to turn off the A/C on my other vehicles to lessen the load on the accessory drive belt during start-up too when alternator drag is the highest.



Greg

 

[cwsoules]

Thanks

When I climbed in my truck this morning I found that some dummy had left the exhaust brake on!! Strangely with it off the engine cools. The info on A/C is a good input and I'll try to remember it when it finally warms up enough to nee A/C again.