Update on EGTs when Towing

[Rollingon]

A few months ago I posted the results of an EGT test pulling a 15k trailer up a long grade. http://forum.thedieselpage.com/ubb/ultimatebb.php?ubb=get_topic;f=3;t=008415
Last week I found that the EGT probe used in that test was bad and gave readings that were too low. This means the conclusions from that test need to be reconsidered.

A month ago my normal EGT readings started dropping. I heard that the early style Edge Attitude probes sometimes would work their way out of the manifold and become shrouded by the bushing threaded into the manifold. Sure enough, when I removed the probe and bushing, the sensor tip had slipped inside the bushing and was badly shrouded. I installed a new style probe from Edge and the readings came back up, but to a higher level that they had been at the time of the test. It looks like the readings in the test were too low (maybe the sensor was in the process of working its way out and was partially shrouded?), which affects the conclusions from that test.

I haven

[Inspector]

In the past I had been trying to match my egt indications. I have the Spa 211 and Attitude in my 03 DA. It had been pretty much imposible to do. I now have installed the upgraded EGT thermocouple that Edge sends out with the new installs and now I have been able to match temps withing about 15 degrees. I had spent a great amount of time centering or trying to center the probe tip in the center of the exhaust manifold tube on the old style probe and just couldn't quite get what I wanted. My Spa probe is in the passenger side manifold and the Attitude in the other side. The Spa used to back out often until I got agressive on the tightening the "B" nut on the probe. I don't generally like to overtighten things but in this case it was just a little extra and it now stays put.
I just had the truck smog checked here in Utah for registration. I took the cat off when I bought the truck and frankly forgot about it. When they put the Vin nbr in the computer it tatteled on me. They looked and of course didn't see it. They failed the smog for that. They did run the test without the cat and at idle it showed 1.4 percent opacity and WOT was 3.08. In my county you are allowed 30 percent opacity before they will flunk a diesel. I put the cat back on and they reran the test and it was actually dirtier that without. Go figure. Anyway thats the story. It now passes with the KITY installed. Its a visual thing.
I try to keep my EGTs from topping 1400 on the long pulls. Usually stays around 1300-1350 pulling hard and about 950 to 1000 cruising.
FWIW.
Denny