I haven't been watching the boost gauge, but it's kind of hard to build boost at this altitude. I have thrown the SES light on overboost before but backed out too soon to really pay attention to how the defueling feels. When I accelerate now the truck takes off fine but slows down quite a bit on the top end of 1st. The 2-3 shift slams hard a lot of the time. Is the slowing overboost, trans, or torque converter? How can I test these? BTW, I cannot get the SES light to come on here at altitude. I read that some trucks defuel w/o the SES light? I have AutoE as well, so is there anything I could do with that to see what's going on?

Thanks!

 

Can't help you buddy, but here's a bump.

For what it's worth, I've only thrown the SES light a couple times living at 5600' of altitude in Colorado with my truck, DP tuner, etc. I do have the boost dumping (I need the boost fooler thingy). My tranny doesn't behave like you are describing so can't help you there.

 

I think the engine is starving for fuel at high RPM.

 

The strange thing is that it only does it in 1st gear. It almost seems like I don't have a 2nd gear. In 80econ it takes off fine. I think it is a shift at 3K rpm then it drops back to around 2700 for a few seconds after what I think is a shift in to 2nd. That is where the power loss is. After a few seconds I get another shift into 3rd? and the power is great again. Just that one dead spot after I take off. Any thoughts? I looked at the AE pdf files on RHN last night and I'm going to try a couple of those tests. Will post findings prolly this weekend.

 

I didn't know that you had a programmer on it. Now that I know that, all I can tell you is that I don't diagnose problems when a programmer is on the truck. I have no idea what they do, but in my experience they often cause problems.