Power loss+ Surging

Alright, so my truck has finally started giving me it's first lick of trouble.
Loss of power(feels like I'm towing a trailer) and will surge as I give it gas. You can hear the throttle opening up, but it just makes noise, hardly moving the truck.
It's random, comes and goes, no CEL.
You can floor it, and it'll feel like you're hauling a loaded trailer.
Does the same under part throttle, just not as noticeable.
I cleaned the MAF last night(with MAF cleaner), didn't seem to make any difference.

Plugs are 10k old
Changed the oil about 3 weeks ago.
Ran through two tanks of gas, problem persists.

Hard to track something like this down from scratch without any CEL, so I was hoping someone else has had this issue themselves, and resolved it.

Thanks for any help.

 

Could the cats be clogging up? I had a similar issue long ago but once mine clogged they stayed that way. It wasnt intermittent. Do you hear any strange engine sounds like it could be missing or stumbling? Is it automatic or manual

 

I thought about that, but the cats only have about 20k miles- I installed new ones when I made my custom exhaust.

No weird engine noises. Manual 4.0

 

Not sure if this is your problem, but I had the exact same symptoms on my truck. It would come and go, but it felt like the truck was starting off in 3rd gear when leaving a stop. Long story short, I had one bad VVT solenoid and both VVT screens in the heads were nearly clogged. Either problem will prevent the cam in that head from advancing at low RPM and make it run like shit. The VVT solenoids are at the front of the head on the intake side. The screens are at the front on the outboard sides of the the heads. I posted pics in another thread asking about similar issues. As soon as I cleaned the screens and replaced the solenoid it ran great and the problem has never returned.

Oddly enough I had no CEL's and torque scan showed nothing. Hard to believe a problem like this doesn't trip a code, but it doesn't - at least for me. Anyway, if you run out of ideas you might want to check these issues out.

 

That would make a lot of sense.
Any link to that thread?
Are those screens easy to clean? How do you go about checking those solenoids?

 

Passenger screen is easy as pie to get out. Driver's side requires unbolting the alternator and moving it out of the way. Spray the screens off with brake cleaner and blow them with compressed air and they're good as new. To test the solenoids, pull them and apply 12V across the two pins. The pintle on the inside (you can see it through various windows or holes) should move fully up and down with no hesitation. One of mine had a burr or something else wrong, because it would stick 3 out of 4 times when I applied power. I actually just ended up replacing both. They're available on Amazon by Dorman. I recall them being around $100 each.

 

Awesome! I'll go ahead and clean/check those when I next get a chance.

Even if it's not the issue, wouldn't hurt to clean those screens.

 

LH solenoid is part number 15340-0P010

RH solenoid is part number 15330-0P010 (these are the Dorman updated part numbers. The OEM ones have a different number)

Both on Amazon right now for $116 each

 

This will give you an idea of where the screens are. This pic is leaning over the passenger side fender:



And this is what the VVT solenoid looks like. It's about 4 inches long. You can see the pintle inside the valve that moves up and down when 12V is applied:



Again, not sure if this is your problem. You'll have to test the solenoids AND check the screens to be sure. But I chased this problem for a year before figuring it out. Based on my significant amount of research chasing this problem a few years ago, this appears to be a pretty rare problem. But hey, it happened to me so it's not impossible.

 

Awesome, thanks @Fullboogie
I think I'll have some time on Thursday to give this a shot.

Weather should be about 25* cooler by then, so I hope my issue isn't temp related.