[TJC]

I've been trying to figure out why my truck RPM drops low and then has a rough idle after stopping while driving with OD off at 60-65 MPH, especially while towing the camper. It runs great in OD at 70 MPH and idles fine when I come to a stop, even towing the camper. This seems to be related to running at high RPM/Heat. I changed the CPS and the IPR. I did a 3300 RPM run in park for 3 minutes to check for Oil Aeration, and when I let off the throttle at the end of the test, the truck dies. (See Data Log) It will start right back up, but runs a little rough compared to before the test. I would be happy to log other parameters if someone thinks it would help them diagnose. Please Help...I'm at a loss.

 

[Gator5713]

This won't help you diagnose your problem but I pull heavy regularly at highway speeds. 20k regularly and used to pull a lot more! I'd run OD off until I was up to about 60 then go ahead and kick it back in. If I was in hills I'd turn it back off but only run 50-55 max. Works great and doesn't overdo the motor running high rpm for long times...

 

[TJC]

Thanks Gator...My truck does OK with EGT's pulling from 65 up here and there, but in traffic where I have to keep going down to 60-65 then get back in the throttle, it gets too warm. I don't go over 65 if I'm keeping the OD off...this is about 2500 RPM. I don't think that RPM is a problem, except for on my truck. This one has me stumped.