engine noise
Thread Starter
6th Gear
Joined: Aug 2004
Posts: 6
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engine noise
have noticed that if my car sets for more than a few days without being started, i get a rattel/ knocking sound that is more severe the longer the car goes without being started. this also occurs at shut down sometimes, also have a constant ticking sound. wondering if this is a ls1 thing or should i take it in too the dealer - which i hate to do!
only 1600 miles on it and never abused.
only 1600 miles on it and never abused.
Race Director
Joined: May 2000
Posts: 14,542
Likes: 5
Rattle at shutdown could be the clutch (if it's in neutral and the pedal is not depressed). Normal.
Ticking and knocking could be piston slap or carbon buildup (not likely at 1,600 miles). Both are normal for the car.
I would drive it until something worse happens, but those both sound "normal" given your mileage.
Ticking and knocking could be piston slap or carbon buildup (not likely at 1,600 miles). Both are normal for the car.
I would drive it until something worse happens, but those both sound "normal" given your mileage.
Pro
Joined: Mar 2004
Posts: 653
Likes: 0
It's presumable that the lifters bleed down while the engine sits, and it takes a few revolutions to re-pressurize them...during this time, you have slack in the valvetrain which causes rattling noises.
My old Nissan truck did this for its entire 90K mile existence. First start each morning was a rattling fiesta. I tried different oils, different filters, no effect.
In the case of my LS1 and the 4.8L iron version in my truck, I get no such noise no matter how long they sit. Both run the same oil most of the cold months...German Castrol 0W-30. In the warm months, the truck gets Amsoil 5W-30 and the car gets Mobil-1 15W-50 (lots of track time). The car has minor audible piston slap type noise on cold startup and for the first few miles (it's an '01).
My old Nissan truck did this for its entire 90K mile existence. First start each morning was a rattling fiesta. I tried different oils, different filters, no effect.
In the case of my LS1 and the 4.8L iron version in my truck, I get no such noise no matter how long they sit. Both run the same oil most of the cold months...German Castrol 0W-30. In the warm months, the truck gets Amsoil 5W-30 and the car gets Mobil-1 15W-50 (lots of track time). The car has minor audible piston slap type noise on cold startup and for the first few miles (it's an '01).
Safety Car
Joined: Jul 2002
Posts: 3,874
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From: Fishing Somewhere Cold
St. Jude Donor '11-'12-'13, '15
Ticking and knocking could be piston slap or carbon buildup (not likely at 1,600 miles). Both are normal for the car.
I would drive it until something worse happens, but those both sound "normal" given your mileage.[/QUOTE]
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First off Piston Slap is NOT NORMAL especially for a 04 model! The ticking you may be hearing while engine is started and idling is possibly the sound of your injectors firing. This IS NORMAL. It is possible that the louder sound you hear at start up is the lifters pumping up after not being started for awhile and bleeding down, but I also go for long intervals without driving my car and have not noticed this condition. I would monitor the condition and if it worsens take her in for a checkup!
I would drive it until something worse happens, but those both sound "normal" given your mileage.[/QUOTE]
________________________________________ ____________________
First off Piston Slap is NOT NORMAL especially for a 04 model! The ticking you may be hearing while engine is started and idling is possibly the sound of your injectors firing. This IS NORMAL. It is possible that the louder sound you hear at start up is the lifters pumping up after not being started for awhile and bleeding down, but I also go for long intervals without driving my car and have not noticed this condition. I would monitor the condition and if it worsens take her in for a checkup!
