RPM’s Jump between 1000-3000 rpms after start

[Jonathan Floyd]

  Hey guys and gals I was hoping y’all could help me with something. I have a 2019 trail boss with the 5.3  6 speed and recently just got over 10,000 miles on it and now when I start the engine rpms Jump for a few Seconds but then it does go back  down under 1,000 rpms and stays there like normal and it’s happen more often now. Any ideas what might be causing this? 

Edited February 6, 2020 by Jonathan Floyd

[tlaw91]

Take it to the dealership, you paid good money for your truck and it is under warranty.

You need a specialist like myself to inspect this and determine why it is happening.

-GM Tech


Sent from my iPhone using Tapatalk

[steelerdude15]

I had an issue similar to what you're experiencing. When I would start my truck cold, the idle would slowly surge between 1000 rpm to 1500 rpm for a few seconds. I cleaned the throttle body, mass air flow sensor and made sure all of the tubing was on tight. The problem went away for me after that.

[Jonathan Floyd]

18 hours ago, tlaw91 said:

Take it to the dealership, you paid good money for your truck and it is under warranty.

You need a specialist like myself to inspect this and determine why it is happening.

-GM Tech


Sent from my iPhone using Tapatalk

Yeah I took it today and the dealership said they couldn’t find anything wrong no codes were popping up and everything looked fine.

[Jonathan Floyd]

17 hours ago, steelerdude15 said:

I had an issue similar to what you're experiencing. When I would start my truck cold, the idle would slowly surge between 1000 rpm to 1500 rpm for a few seconds. I cleaned the throttle body, mass air flow sensor and made sure all of the tubing was on tight. The problem went away for me after that.

If it happens again I’ll do that