Valve clatter
#1
Administratus Emeritus
Certified Car Nut
Thread Starter
Valve clatter
Almost since the engine was new (and before nitrous injection) every so often immediately at startup, I get a loud what sounds like a multi valve clatter. This summer it is happening more often. Anybody else with a Northstar has this condition? It only happens for like a second.
#5
Senior Member
True Car Nut
Join Date: Sep 2006
Location: Somewhere south of Ottawa with your girlfriend driving faster then you.
Posts: 3,277
Likes: 0
Received 0 Likes
on
0 Posts
yup i have the same... but mine isnt just one start up...
I think the new engine is on order... gotta love warranty.
I think the new engine is on order... gotta love warranty.
#6
Administratus Emeritus
Certified Car Nut
Thread Starter
Done some researching through the Cadillac forums and came up with that it sounds like what they describe as "cold carbon rap". Rather than steal another forums text I am linking here to a nice read on the problem. The only solution seems to be a good injector cleaner and some real WOT'* after the engine is hot. After reading the thread I realized without my license my car hasnt seen much upper RPM exercising lately. Northstar tolerances are so close that they build up carbon very easily.
http://www.cadillacforum.com/m_2400/tm.htm
http://www.cadillacforum.com/m_2400/tm.htm
#7
Senior Member
True Car Nut
Join Date: Sep 2006
Location: Somewhere south of Ottawa with your girlfriend driving faster then you.
Posts: 3,277
Likes: 0
Received 0 Likes
on
0 Posts
all without creating a spectical of yourself and attracting the attention of cops. You can do it on most any freeway and stay within the 70-75 MPH range allowable. Once a week like this will keep the engine cleaned out and healthy and is DEFINITELY recommended for the Northstar in particular.
I do notice after a good **** run she is quieter and sounds healthier. I will sometimes coming off the Highway shift in to 2nd to create what he refers to as over run.. But on a engine as sophisticated as the LD8 is this really necessary ?
Thread
Thread Starter
Forum
Replies
Last Post