engine reving at startup
 

Recently I have been trying to find a small oil leak . Which I assume is coming from the remote filter lines. No suprise. I was under my truck and with simplesimple green and hosed it down. Then sprayed the entire oil pan where the nuts are with brake clean. Nothing else was recently done.

This morning when I started it. It started fine....then went from 500 to 1500 rpm...and kept doing it....then I was driving and stopped and it seemed fine

Any reason why its doing this? TIA!

The computer controls the idle speed, You may just have carbon building up which can effect the idle speed.

The IAC is the idle air control valve on the throttle body. It is held in place with 2 screws. Remove the IAC from the throttle body and clean the IAC pintle and the bore in the throttle body with carburetor cleaner spray. Then disconnect the battery for at least 30 seconds to clear the computers idle speed memory and start the engine.

https://blazerforum.com/forum/attach...ine=1406045220
https://blazerforum.com/forum/attach...ine=1406045220

awesome visuals! will give this a try tomorrow when i pick up a can of carb cleaner. will post if this was the fix, after work today it didnt do it, so maybe its not too bad of a build up in there
i recently cleaned the egr valve and replaced the gasket with the screened version, didnt know if this would have affected it