Here is the case. I drive a 150 mile trip once a week, mostly 60-65 mph highway. Well in the last 3 months it started randomly bogging down slightly with the cruise on. I can be going along and its like a strong gust of wind hits the truck from the front. It will make the engine bog then it like releases or frees up and the truck carries on. I also noted on my edge evo (not programmed just plugged in for the gauges) that it shows the engine load shoot from about 30% cruising to about 80% when it have its issue then on the sort of POP release the load goes back down to the normal range. The entire bog down only lasts about 3-5 seconds and I can power out of it by pressing the gas. It may happen 15 times on the trip may only happen once or twice...very random...HELP!
Things I have tried

Replaced plugs and COPS
Replaced FPDM
Cleaned MAF and TB
Replaced Air Filter
Changed Oil
Fuel Filter changed in November

 

if the engine load goes up and the power goes down then it points to the transmission, in my opinion.

Could be an issue in the rear diff too I suppose.

This is just a somewhat-educated guess based on the fact the power goes down but the engine readout shows the load is going up. If it were a spark/fuel supply issue I don't think the load would go up???

 

Check for a sticky/dragging parking brake.

 

First - you need to understand what Load is, in this context:

http://obdcon.sourceforge.net/2010/0...ed-load-value/

MGD

 

huh... so "load" is basically a measurement of air flow?

Now that I know that... do your RPMs increase as the truck feels like it bogs down? I'm guessing probably not.

Sounds to me like it might be an issue with the MAF sensor. I doubt your air flow is really increasing but the computer thinks it is and then compensates by pushing in more fuel. I'd try putting a new MAF sensor in it.

Thats my best theory, at least till MGDfan replies with information that counters my theory!

 

Have catalytic converters checked.

 

I tried cleaning the MAF and nothing seemed to change.
Could be the CATS ( I hope not)

 

I know you tried cleaning the MAF... but if it is bad then cleaning it wouldn't help.
(or possibly it could have been damaged during cleaning)

 

Jeeez .. I hope not. Cleanin' is a 'no-touch' operation.

MGD

 

I dont see how it would idle fine, run fine 95% of the time if the MAF was BAD. It should show bad symptoms constantly if it was defective and its pretty pricy to just buy a new one to try. I did not touch it when I cleaned it and it was doing this pre cleaning as well.

 

I'm with GLC, The E-Brake on the 2004 is known for random sticking and dragging .