High Idle only after engine has completely cooled down

Tiny
JAMMIE64
  • MEMBER
  • 2003 CHEVROLET IMPALA
  • 3.4L
  • V6
  • 2WD
  • AUTOMATIC
  • 113,000 MILES
I start it drive 25 minutes to work and it's fine. After it sits all day it's fine.
If I go out and restart it before the engine completely cools down, it will idle way too high. Seems to be heat related. I replaced much of the cooling system last year (head and lower gaskets, radiator, water pump) as it ran hot. That problem solved now this high rpm. Perhaps it's a vacuum leak? I might have put the hoses back on wrong after disassembly. Any ideas? Hose diagram or photo of another 3.4 might help? Thanks!
Do you
have the same problem?
Yes
No
Thursday, June 25th, 2020 AT 1:45 PM

1 Reply

Tiny
JACOBANDNICKOLAS
  • EXPERT
Hi,

I attached two pics for you to review. They are the vacuum routing schematics. Let me know if they help. Also, here is a link that explains how to check for a vacuum leak:

https://www.2carpros.com/articles/how-to-use-an-engine-vacuum-gauge

Let me know what you find.

Joe
Was this
answer
helpful?
Yes
No
Thursday, June 25th, 2020 AT 7:29 PM

Please login or register to post a reply.

Sponsored links