Home | Contact Us | FAQ | Search & Site Map | Link to Us
Sign In | Join | Other 45 Sites in Network
HomeAnnouncements
Discussion Groups
By Brand
BMWChevroletDodgeFordGMHondaLexusMercedes-BenzNissanPeugeotToyotaVolkswagenOther Brands
By Topic
4x4 CarsRVsDrivingMaintenance & RepairCar AudioCollectible Cars
Country Specific
Australian ForumsUK Forums
ArticlesAuto InsuranceBuyingCars & TechnologyMaintenanceMiscellaneousSafety
DMV Resources
Related Topics
MotorcyclesBoatsMore Topics ...

Car Forum / GMC Cars / January 2006

Tip: Looking for answers? Try searching our database.

knocking when truck starts and at certian rpm

Thread view: 
Enable EMail Alerts  Start New Thread
Thread rating: 
weltz - 14 Jan 2006 21:03 GMT
Every time that I start my truck and it hasn't been running for a while it
eill knock when I start it.  within about a min. or so it will fade
away.But then it will also nock at about 1500 rpms.  What the heck is
wrong woth my truck?  Wil I be ablr to fix it?
Shep - 14 Jan 2006 21:28 GMT
What heck is the truck, we are suppossed to guess that too?
> Every time that I start my truck and it hasn't been running for a while it
> eill knock when I start it.  within about a min. or so it will fade
> away.But then it will also nock at about 1500 rpms.  What the heck is
> wrong woth my truck?  Wil I be ablr to fix it?
TheSnoMan - 14 Jan 2006 22:25 GMT
> Every time that I start my truck and it hasn't been running for a while it
> eill knock when I start it.  within about a min. or so it will fade
> away.But then it will also nock at about 1500 rpms.  What the heck is
> wrong woth my truck?  Wil I be ablr to fix it?

You may be dealing with tow different kncoks. One sounds like piston
slap/knock when engine is cold and the other sounds like rod knock when
engine is warmed up. It could be a very loose piston the knocks all the
time too. A rod knock and startup would not fade away after a minute or
so but piston slap can as it swells from heat.

Signature

-----------------
www.thesnoman.com

weltz - 16 Jan 2006 13:39 GMT
Thanks for the help snowman!
The Adams Family - 14 Jan 2006 22:57 GMT
I got an idea go to tools, options, click on the tab (spelling), check the
box that says always check spelling before sending!!

Now to answer your question, if it is a 5.7 or 6.0 V-8, or 4.3 V-6, and it
was build on or after 1994 you probably just have piston slap. This gets
noisier at about 1500 rpm, but it usually goes away when the engine is
warmed up. If yours doesn't go away, or gets louder it is probably a rod
bearing.

> Every time that I start my truck and it hasn't been running for a while it
> eill knock when I start it.  within about a min. or so it will fade
> away.But then it will also nock at about 1500 rpms.  What the heck is
> wrong woth my truck?  Wil I be ablr to fix it?
 
Sign In
Join
My Latest Posts
My Monitored Threads
My Blog
My Photo Gallery
My Profile
My Homepage

Start New Thread
Enable EMail Alerts
Rate this Thread



©2008 Advenet LLC   Privacy Policy - Terms of Use
This website includes both content owned or controlled by Advenet as well as content owned or controlled by third parties.