Problem after cam installation!
Thread Starter
Intermediate
Joined: Jul 2009
Posts: 36
Likes: 0
From: South Texas
Problem after cam installation!
I have a 2006 LS2 manual 6. Just installed a 236/236 602/602 113ComCam last week. Having a few problems:
1. Hearing a loud, fast tapping sound coming from the engine. It comes and goes.
2. Whenever I push my clutch in to stop, RPMs drop down to almost 0 and then go back up to 800 and sits at idle.
Just wondering if anyone has ever experienced anything like this?
1. Hearing a loud, fast tapping sound coming from the engine. It comes and goes.
2. Whenever I push my clutch in to stop, RPMs drop down to almost 0 and then go back up to 800 and sits at idle.
Just wondering if anyone has ever experienced anything like this?
Moderator
Joined: Dec 2002
Posts: 40,882
Likes: 4,333
From: Lakewood Ranch, FL
I have a 2006 LS2 manual 6. Just installed a 236/236 602/602 113ComCam last week. Having a few problems:
1. Hearing a loud, fast tapping sound coming from the engine. It comes and goes.
2. Whenever I push my clutch in to stop, RPMs drop down to almost 0 and then go back up to 800 and sits at idle.
Just wondering if anyone has ever experienced anything like this?
1. Hearing a loud, fast tapping sound coming from the engine. It comes and goes.
2. Whenever I push my clutch in to stop, RPMs drop down to almost 0 and then go back up to 800 and sits at idle.
Just wondering if anyone has ever experienced anything like this?
Racer
Joined: Sep 2005
Posts: 279
Likes: 1
From: montrose colorado
A fast tapping sound might be something in the valve train, loose rocker, lifter not pumped up. Normal noise with larger cams.
The dropping idle is common with cams, however a good tuner can tune it out using something called minium idle air flow tables. Ask SpinMonster he knows. My tuner drilled a hole in the throttle plate this is NOT the recommened solution.
Hope this helps
Donald
The dropping idle is common with cams, however a good tuner can tune it out using something called minium idle air flow tables. Ask SpinMonster he knows. My tuner drilled a hole in the throttle plate this is NOT the recommened solution.
Hope this helps
Donald
Burning Brakes
Joined: Nov 2009
Posts: 1,023
Likes: 0
From: North Bay CA
Could be the wrong size push rods...I had that problem after installing a cam. After going back to a LS6 cam and the correct push rods the sawing machine sound went away. I agree that a good tuner will cure the the idle problem.
Last edited by FastGhost; May 10, 2010 at 10:55 PM.
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From: Now in God's Country, the Big Sky, Montana!
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St. Jude Donor '06-'07-'08-'09-'10-'11-'12
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From: Colorado Springs, CO
St. Jude Donor '08-'09-'10-'11
A fast tapping sound might be something in the valve train, loose rocker, lifter not pumped up. Normal noise with larger cams.
The dropping idle is common with cams, however a good tuner can tune it out using something called minium idle air flow tables. Ask SpinMonster he knows. My tuner drilled a hole in the throttle plate this is NOT the recommened solution.
Hope this helps
Donald
The dropping idle is common with cams, however a good tuner can tune it out using something called minium idle air flow tables. Ask SpinMonster he knows. My tuner drilled a hole in the throttle plate this is NOT the recommened solution.
Hope this helps
Donald
The idle is airflow table related and is easily fixed with a tweak.
The noise is from a lifter. What size pushrods do you have?
Safety Car
Joined: Feb 2008
Posts: 3,712
Likes: 3
From: TEXOMA
St. Jude Donor '08-'09
you need to measure in order to get the right ones, probley shoot for the 7.425. but only a pushrod lenth checker will confirm.
goto a speed shop and grab one.
then pull up ls1tech and do a search on howto measure.
goto a speed shop and grab one.
then pull up ls1tech and do a search on howto measure.
Race Director
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From: Now in God's Country, the Big Sky, Montana!
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St. Jude Donor '06-'07-'08-'09-'10-'11-'12
Thread Starter
Intermediate
Joined: Jul 2009
Posts: 36
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From: South Texas
The tapping sound started on one side of the engine and then seemed to move to the other side of the engine now. I drove the car today and the tapping was very loud at first and then it went away completely. After driving a few more miles, the tapping came back again.
If this is a lifter issue, would the tapping come and go?
Or is it maybe trash in the engine?
If this is a lifter issue, would the tapping come and go?
Or is it maybe trash in the engine?
Instructor
Joined: Jan 2003
Posts: 110
Likes: 0
From: Austin TX
I was under the impression the sewing machine noise was normal for big cams. The valves are opening and closing violently in comparison to a stock cam, and the springs are heavier(or should be).
Can't remember if you listed headers, but those will allow the noise to resonate right to the interior.
I have a moderate cam in my 08 C6, it makes a light sewing machine noise--but it sounds in harmony with the engine, nothing seems out of place.
Can't remember if you listed headers, but those will allow the noise to resonate right to the interior.
I have a moderate cam in my 08 C6, it makes a light sewing machine noise--but it sounds in harmony with the engine, nothing seems out of place.