Hesitation at full throttle, normal power at partial throttle

[Bsgiffor]

2002 Yukon
313000 miles
Brand new plugs, wires last week
Tried 91 octane fuel and no change
Tried seafoam no change
Check engine light on
Check engine light will stay off if I unplug battery, and stay under 50mph(ish)- usually turns back on if I get on the freeway

Hey guys my truck listed above falls on its face when starting from a dead stop going right to full throttle. What's weird is if I push the accelerator to 3/4 or just a hair before full throttle the truck has power and accelerates harder than if I were to floor it. After a few seconds( literally), the truck will take off and rev thru the range and bang off ever gear and accelerate as one might expect from a slightly worn motor as I have.
It's dangerous at times when trying to turn into a road with traffic or other situations when I need power right off the bat. Anyone ekes have this issue? I was thinking O2 sensors next.


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[kaoticx]

Yea, O2 sensor.
Or maybe Throttle Position?

 

[afpj]

Did you clean TB and MAF? Check fuel pressure, fuel filter.

 

[08grey]

What's the code?

 

[Bsgiffor]

I don't know what the code is. I guess I'll go go auto zone and get it read. I haven't checked the throttle body, or maf, but fuel pump and filter are new.
I've been reading up and I was thinking a bad knock sensor may need to be changed. A knock sensor pulls timing out if it's faulty or senses specific things? I will check the throttle body, and maf snd figure out the code. What are the chances it is the knock sensor?


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[08grey]

Definite get the code and we can help from there

 

[Bsgiffor]

P0332- knock sensor. Holy cow the Delco sensors are 70 dollars a piece and I need two, plus the intake manifold gasket is 75 bucks. Didn't expect to be spending 230 bucks to fix this but I hope it makes the truck accelerate like normal. It feels like it's got a v6 in it now. Especially on hot 100 degree days here in Arizona.


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[08grey]

There are lots of threads and how to for changing the knock sensors. They mention sealing the top with silicone and I think I remember you should get oem sensors. Search the interwebs for it

 

[Bsgiffor]

Well that's why I mentioned the Delco sensors. Are they not oem? The other option was the autozone duralast sensors which are like 50 bucks each but why not do it right, right? I will check out the web for sealing the sensors with silicon and other tips as you suggest. Thanks for the tip


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[jp.maritz]

Try rock auto.com for your parts and sensors they sell acdelco too for a lot less than autozone


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