2004 Chevy Silverado wont idle

Tiny
ASUPINGER1
  • MEMBER
  • 2004 CHEVROLET SILVERADO
  • V8
  • 4WD
  • AUTOMATIC
  • 100,460 MILES
I was getting on the hiway and noticed a slight loss of power and acceleration unless I floored it then it was fine. When I stopped at the off ramp light it would not idle on its own. I can push the gas and it feels smooth over 2000 rpms. So ichanged the maf sensor, spark plugs, wires and even the catalytic converters. Still runs rough at low rpm and wont idle at all. But will start right back up. Can you help me. My check engine light is on and get codes P0300 and P0101. A garage checked it and said it was that cats. But it wasnt.
Monday, April 7th, 2008 AT 7:53 PM

4 Replies

Tiny
DENNYP
  • MECHANIC
  • 1,824 POSTS
The first step would be cleaning the throttle body out. If you have carbon buildup in the throttle body, it will cause poor or no idle quality. If this doesn't help, try to determine which cylinders show misfires. Let me know what you find.
Was this
answer
helpful?
Yes
No
Thursday, February 18th, 2021 AT 12:41 PM
Tiny
ASUPINGER1
  • MEMBER
  • 3 POSTS
I checked the engine compression and one cylinder had no compression at all so I removed the valve cover and that cylinder has a broken valve spring. The throttle body was fine.
Was this
answer
helpful?
Yes
No
-2
Thursday, February 18th, 2021 AT 12:41 PM
Tiny
DENNYP
  • MECHANIC
  • 1,824 POSTS
Was it the driver side rear cylinder? I have seen about 5 different silverados with broken valve springs in the same location. 4 of them just got valve springs, 1 of them had to get a cylinder head.
Was this
answer
helpful?
Yes
No
Thursday, February 18th, 2021 AT 12:41 PM
Tiny
ASUPINGER1
  • MEMBER
  • 3 POSTS
It was the second cylinder from the front on the drivers side. And the rear spring on that cylinder. If you had heard of that before then a clue might of saved me alot of time and money.
Was this
answer
helpful?
Yes
No
Thursday, February 18th, 2021 AT 12:42 PM

Please login or register to post a reply.

Sponsored links