2014 Yukon slow acceleration

[AWP84]

Hello new here not sure if this is where to go for this but here it goes. Yesterday I was running errands and at a stop light I noticed a lack of acceleration through 2nd gear. Once it hits third it starts accelerating normally also noticed a rattling sound while accelerating until it hits third then I don’t hear it anymore. In park I hit the gas and engine revs up like normal but not when in gear. Not sure if it’s related but about a month ago a couple times my abs light came on along with stabletrak off and traction control off lights and message no check engine light for any of my issues. Can someone please help don’t want to go to the mechanic unless I have to. I have also cleaned throttle body and maf sensor. Thanks

 

[Doubeleive]

Hello new here not sure if this is where to go for this but here it goes. Yesterday I was running errands and at a stop light I noticed a lack of acceleration through 2nd gear. Once it hits third it starts accelerating normally also noticed a rattling sound while accelerating until it hits third then I don’t hear it anymore. In park I hit the gas and engine revs up like normal but not when in gear. Not sure if it’s related but about a month ago a couple times my abs light came on along with stabletrak off and traction control off lights and message no check engine light for any of my issues. Can someone please help don’t want to go to the mechanic unless I have to. I have also cleaned throttle body and maf sensor. Thanks

I would start with the historical issue of the ABS/stabiltrac, it's possible if a hub or abs sensor is going out and it is not seeing the wheel speed corectly it might cause your issue. Usually that only affects braking though. At any rate those codes should be stored if not currently lit up unless you have cleared them or disconnected the battery.
you need a scanner that can specifically read ABS, bottom of the barrel scanners do not.

 

[gooffeyguy]

I've also heard on here about some people having problems after cleaning the throttle body and not performing a reset or relearn. Not sure what that entails though.

 

[mikez71]

WOW!, that sounds like my problem exactly!

(rattling sound you hear is probably setting off your knock sensors which will retard timing)

In my case, the sensor readings look good, plugs and wires look good. Getting to the coils and knock sensor..
I also have severe knock retard (upto 16 degrees timing pulled!) Not sure if ignition miss is causing knock or what...

 

[AWP84]

I've also heard on here about some people having problems after cleaning the throttle body and not performing a reset or relearn. Not sure what that entails though.

I cleaned it as a possible solution to the issue not before having issue.

 

[AWP84]

I would start with the historical issue of the ABS/stabiltrac, it's possible if a hub or abs sensor is going out and it is not seeing the wheel speed corectly it might cause your issue. Usually that only affects braking though. At any rate those codes should be stored if not currently lit up unless you have cleared them or disconnected the battery.
you need a scanner that can specifically read ABS, bottom of the barrel scanners do not.

Would autozone have that scanner?

 

[Doubeleive]

Would autozone have that scanner?

I am sure they have one for sale, the one they use for there "free" scan might not read abs, depends on the store
they should carry the "innova" brand for sale and it's probably around $300, you could probably get a half-way decent autel off of amazon for the same price, the better autel's are closer to $500 there are so many models hard to pick-n-choose. kinda gotta just weigh the pros & con's of what best suites your needs. a scanner is a investment, some higher upfront cost but pay's off in the long run because you can diagnose stuff and each time you do that is money back in your pocket that you didn't have to fork over to someone else.

 

[Joseph Garcia]

As @Doubeleive stated above, if you plan to keep the truck for a while, get yourself a quality bi-directional scanner to add to your tool box. Then, you will be able to read ALL codes, along with a brief explanation/pointer to the source of your issue. You will literally save thousands of dollars in diagnostic and repair costs over the life of your truck, and you will most likely recoup the cost of the scanner within 1 year.

 

[Foggy]

Check your starter/ flexplate. The starters on these will start to rattle badly
but not cause a starting issue.
This may be setting off the knock sensors.
Check this for mikez71 as well on his problem

 

[mikez71]

Leaning towards checking the cat converters myself.. 3rd cat was fine, but that's way downstream..

You're not kidding about the starters rattling. I removed mine for motor mounts and have never felt such a loose jangling part in my hands before!
That was one of the more obvious preventative maintenance items. Cheap and easy to boot. One knock sensor is right near the back end of it..

Curious if the OP's truck drives like mine. Seems to feel normal immediately after startup, but once it warms up in a few seconds, bog...