Idle bogs on deceleration to stop

[Lftwfls]

Hello All,

 

Problem: The idle feels like it bogs down when rolling to a stop, and applying the brakes firmly. (that last 10 feet of braking) I believe it may be when cold only.

 

Background: I bought a used 2018 Silverado 1500 double cab LS 4x4 with 100,000 miles. I drove it without issue for a few months, and then started doing the 100k miles services myself. So far I have changed the oil, the differential fluids, the trans fluid, and transfer case fluid. I have not yet changed the spark plugs.

 

I saw online that it might be the Idle Air Controller? If that is the case should I purchase a scanner to see if there are air/fuel mixture codes? It is also possible that this is not a flaw and just a random hiccup.

 

 

[steelerdude15]

My truck does this too and I’m only at 35k miles. My guess is that it does it because of how these trucks are tuned, but I could be wrong.

[Lftwfls]

@steelerdude15 I also forgot, it could be an excessively dirty intake butterfly? My truck was used on lease roads in Texas. The dust was so thick in the interior I had to use rubbing alcohol to get it off the plastic.

 

I will take that apart today to see.

 

Edited October 25, 2021 by Lftwfls

[Salsa De Piña]

You're on the right track.  Pull the throttle body and give it a good cleaning.

 

I had a Canyon that did this every few years, and it got worse in the winter time.

Edited October 25, 2021 by Salsa De Piña

[steelerdude15]

6 hours ago, Lftwfls said:

@steelerdude15 I also forgot, it could be an excessively dirty intake butterfly? My truck was used on lease roads in Texas. The dust was so thick in the interior I had to use rubbing alcohol to get it off the plastic.

 

I will take that apart today to see.

 

I’m not sure, but it could be.

[steelerdude15]

6 hours ago, Salsa De Piña said:

You're on the right track.  Pull the throttle body and give it a good cleaning.

 

I had a Canyon that did this every few years, and it got worse in the winter time.

I clean my throttle body every 12,000 miles when I change my air filter. I have less than 1,000 miles to go before it has to get cleaned again. I’ll clean it and report back if it took care of the issue.

[rlcole321]

Seafoam makes a good product for that, it has a special tube that can be routed under the intake tube where you can start the vehicle and clean the whole intake system

 

Sea Foam SS14 Cleaner and Lube - Walmart.com

[steelerdude15]

@Lftwfls I cleaned my throttle body and MAF sensor this weekend. It took care of the issue.

[diyer2]

Regular use of a fuel system cleaner should help. All my motors get it.