Need help figuring this out
Thread Starter
Melting Slicks
Joined: Jun 2006
Posts: 2,064
Likes: 1
Cruise-In 9-10 Veteran
St. Jude Donor '07-'08-'09
Need help figuring this out
I have a 2004 vert that is my driver. The car has been trouble-free and I absolutely love this car. I installed a cam a few months ago, which made it that much better. 
A couple of weeks ago when I went out to start the car in the morning, I could hear a "chirp", which would sporadically come and go. The sound never varied speed, regardless whether it was stopped or going at highway speeds. The car ran fine other than the sound. I thought perhaps it was the belts, so I changed out the belts and the tensioners, checked the fans and shrouds, but still had the same chirp.
Metal has been discovered in the oil filter. I know this is not good.
Further diagnostics are being performed on the car to try to figure out what went wrong.
I've got some knowledge about the runnings of my car, but want to take this opportunity to learn even more.
What else could it be?
A couple of weeks ago when I went out to start the car in the morning, I could hear a "chirp", which would sporadically come and go. The sound never varied speed, regardless whether it was stopped or going at highway speeds. The car ran fine other than the sound. I thought perhaps it was the belts, so I changed out the belts and the tensioners, checked the fans and shrouds, but still had the same chirp.
Metal has been discovered in the oil filter. I know this is not good.
Further diagnostics are being performed on the car to try to figure out what went wrong.
I've got some knowledge about the runnings of my car, but want to take this opportunity to learn even more.
What else could it be?
Last edited by NikiQ; Nov 23, 2010 at 07:06 PM.
Drifting
Joined: Oct 2005
Posts: 1,944
Likes: 24
From: Hurst Texas
St. Jude Donor '07-'08-'09
Beth
Could be valve spring related issue? Recall Jim's problem...started as valve spring issue.
Metal shavings in oil pan...possibly from push rod/spring(s)/stems/retainers/seats?
Generally not good regardless of source...
Did you change springs with the cam?
I'd run it by whoever did the work.
Since its a DD, how many miles since the cam work?
Could be valve spring related issue? Recall Jim's problem...started as valve spring issue.
Metal shavings in oil pan...possibly from push rod/spring(s)/stems/retainers/seats?
Generally not good regardless of source...
Did you change springs with the cam?
I'd run it by whoever did the work.
Since its a DD, how many miles since the cam work?
Drifting
Joined: Sep 2007
Posts: 1,283
Likes: 7
From: Hurst (Fort Worth area) Texas
St. Jude Donor '09
Does it 'chirp' whether sitting or driving?
Could it be a noise from the heat-A/C system?
What is the frequency of the 'chirp' (once a second, ten times a second, whatever)?
Is the 'chirping' frequency constant?
Does it sound 'electronic?'
How loud is it?
Could it be a noise from the heat-A/C system?
What is the frequency of the 'chirp' (once a second, ten times a second, whatever)?
Is the 'chirping' frequency constant?
Does it sound 'electronic?'
How loud is it?
Thread Starter
Melting Slicks
Joined: Jun 2006
Posts: 2,064
Likes: 1
Cruise-In 9-10 Veteran
St. Jude Donor '07-'08-'09
I eliminated the heat/a/c, so it's not that. The sound is constant whether I'm not moving, or at highway speed. The sound has gotten louder over time, but at infrequent times but when I hear it, the frequency is about couple of times a second. I haven't been able to determine any one thing that will get it to occur. Not an electronic sound. I thought the sound was coming from the belts, but I changed them and it still happened.
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Drifting
Joined: Sep 2007
Posts: 1,283
Likes: 7
From: Hurst (Fort Worth area) Texas
St. Jude Donor '09
Le Mans Master
Joined: Nov 2007
Posts: 7,683
Likes: 3
From: La La land cali
St. Jude Donor '09
I had the same thing. Replaced both tensioners (one at a time about a month or so apart)-- it ended up being the idler pulley.
Thread Starter
Melting Slicks
Joined: Jun 2006
Posts: 2,064
Likes: 1
Cruise-In 9-10 Veteran
St. Jude Donor '07-'08-'09
I finally had it taken to a very reputable shop. They heard the sound, and were the ones that found metal in the oil filter. Now I'm just waiting for final diagnostics for a cause. With the holiday weekend, I won't be able to see it until next Monday. I'm wondering if it had anything to do with the cam install.
Melting Slicks
Joined: Aug 2006
Posts: 2,866
Likes: 45
From: Tampa Bay, Go BUCS!!!Go Rays!!!Go Lightning!!!
St. Jude Donor '12-'13-'14
I"d send an oil sample out to be analyzed. That may tell you where the metal is coming from.
I just find it odd that the chirp doesn't vary with speed. It is possible that the chirp and the metal in the oil are unrelated and that you simply found the metal while looking for the chirp. Without the oil information I would have said look at the headers/cats/exhaust and see if it is rubbing.
Has the oil been changed since you did the cam work? I don't mean that same say, I mean days or weeks after? It is possible the metal is from the cam work.
GL
I just find it odd that the chirp doesn't vary with speed. It is possible that the chirp and the metal in the oil are unrelated and that you simply found the metal while looking for the chirp. Without the oil information I would have said look at the headers/cats/exhaust and see if it is rubbing.
Has the oil been changed since you did the cam work? I don't mean that same say, I mean days or weeks after? It is possible the metal is from the cam work.
GL
Melting Slicks
Joined: Dec 2008
Posts: 2,070
Likes: 5
From: N.Richland Hills Texas
Any new metal part introduced to the engine will have "sharp" edges from machining... Even parts that are deburred or camfered will have some little pieces that will stick out and be worn off from rubbing... Changing oil and filter after engine work is a good idea, maybe a couple of times...If your "chirping" is not changing with RPM look for "constants" with the engine running...
Le Mans Master
Joined: Nov 2009
Posts: 6,119
Likes: 156
From: Huntington tx
No change with RPM's eliminates engine related causes. Stop looking in the engine, unless you don't care how much money is wasted. If a shop is now telling you there is metal in the engine filter(where it belongs) and you get a rebuild and the chirp is still there....you may feel violated in an obscene way. Especially if your engine runs as smooth as butter now.
