EGT temps took longer to come down today?

code.mafia · #1 (**permalink**) 11-23-2011, 02:37 PM

I have a CTS and EGT probe. Have had them in for over a week and have been watching them closely as we all should. Turns out I was idling my truck much longer than needed before I got the CTS to bring the EGTs down. Anyway, up until today, I could pull in from wherever I had driven and it only took 30-45 seconds normally for my EGT to drop to 350. Today the high was 62 (not hot by any means), and I had to run an errand (to pick up some fuel additive) this afternoon. It's only 4-5 miles from work. I drove there, pulled up, put in park and waited for my temps to come down. They trickled down MUCH slower than normal. I didn't hot rod it on the way there. 2 miles of it on the highway at 70mph. It finally got into the 370's, briefly hit 368, then back into the mid 370's. I waited several minutes and they never got lower. I finally turned it off, went in, got my stuff and went back to work. Same thing. On the way home, same thing.

I had the heater on. Turned the temp up to 90, fan on full blast, didn't make a difference. Turned it down to 68 and fan on low, no difference.

Why would it cool down slower today?

**Galaxie** · #2 (**permalink**) 11-23-2011, 02:54 PM

Did you have your AC or defroster on? It will take a bit longer running your AC pump.

code.mafia · #3 (**permalink**) 11-23-2011, 02:55 PM

Nope, no AC, just the heater. I did have it blowing on defrost though.

code.mafia · #4 (**permalink**) 11-23-2011, 02:56 PM

The vent it's blowing out of shouldn't matter. Only that the heater is on and AC is off to pull heat out of the coolant.

the_turtle · #5 (**permalink**) 11-23-2011, 03:15 PM

Not sure about the 05's but some vehicles run the ac when in defrost... Just a thought.

**Galaxie** · #6 (**permalink**) 11-23-2011, 03:37 PM

If you had your defrost on, your AC pump should be running to dry. When it is warmer out, my EGTs take a bit to come down below 400 with that pump running.

kdogg85 · #7 (**permalink**) 11-23-2011, 03:38 PM

Check your boost tubes(boots mainly), manifolds, and up pipes and see if a small leak has developed. won't hurt anything and won't take too much time.

code.mafia · #8 (**permalink**) 11-23-2011, 03:42 PM

I will turn defrost off tomorrow. Going bow hunting early in the morn. Thanksgiving family tradition. I've got a charged air tube in the mail from a single alternator truck. When it gets here I'll check the rest of the charged air tubing.

I did have my first diesel race last night, another F250, on the highway from 70mph...smoked him. Maybe I blew a tube/hose...