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Car runs perfect for a few miles. Then the valves will get very loud, but it does not lose power.. I can turn car off and wait about 15 minutes
and start it back up. It will be quite and running perfect. The I can drive it again and it starts doing the same thing. Please help.
 

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Sounds like maybe it's an oil viscosity issue, making noise when the oil gets warm and thins-out. Everything under the front cover is hydraulic in one way or another on both 2.5's and 3.5's. The IVT valves and phasers and chain tensioners are all hydraulically operated, they depend on proper oil pressure and good seals. If the tensioner(s) are worn or out to the limits, you may be hearing chain clatter and not valves. First thing, make sure your oil level is right and put a stethoscope on the valve cover(s) and front cover to determine where the noise is really coming from. Also stream the EOP sensor with a scanner (or put a mechanical gauge on it) and make sure your oil pressure isn't falling way off. Depending what you find, go from there.
 

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Car runs perfect for a few miles. Then the valves will get very loud, but it does not lose power.. I can turn car off and wait about 15 minutes
and start it back up. It will be quite and running perfect. The I can drive it again and it starts doing the same thing. Please help.
It does sound like you may be losing oil pressure once the engine warms up. Does your oil light on the dash ever come on? What type of motor oil are you using and how often are you changing it and the oil filter? You can check the pressure very easily by installing a temporary mechanical oil pressure gauge. You would remove the oil sensor which is located next to the oil filter and install a mechanical oil pressure gauge in it's place; you may need to get an 1/8 BSPT to 1/8 NPT adapter to hook up the gauge.
With the engine fully warmed up, the pressure should be as follows:
idle - at least 14 psi
2000 RPM - 43 psi

If you find the pressure to be extremely low at the higher rpms, it could be due to a plugged up oil filter, plugged up oil pickup, bad oil pump or worn rod/main bearings; don't let it go for too long or else your engine will end up going to heaven.
 

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It does sound like you may be losing oil pressure once the engine warms up. Does your oil light on the dash ever come on? What type of motor oil are you using and how often are you changing it and the oil filter? You can check the pressure very easily by installing a temporary mechanical oil pressure gauge. You would remove the oil sensor which is located next to the oil filter and install a mechanical oil pressure gauge in it's place; you may need to get an 1/8 BSPT to 1/8 NPT adapter to hook up the gauge.
With the engine fully warmed up, the pressure should be as follows:
idle - at least 14 psi
2000 RPM - 43 psi

If you find the pressure to be extremely low at the higher rpms, it could be due to a plugged up oil filter, plugged up oil pickup, bad oil pump or worn rod/main bearings; don't let it go for too long or else your engine will end up going to heaven.
I use Mobil One 5w/30. Have used since car was new. Change oil and filter every 6000 miles. Sometimes I can drive 30 miles or more and nothing happens. Car stays quite and runs perfect.
As I said earlier, I can turn it off for about 10 to 15 minutes and start it back up. It will run perfectly at idle and high speed.
 

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Sounds like something is sticking hydraulically when warm and gets un-stuck when you shut it down. IVT solenoids, IVT phasers, hydraulic chain tensioners, and various oil pump components can all cause this. It would be really helpful to let a stethoscope tell you whether the noise is from somewhere under the front cover or valve cover, and approximately where on those parts.
 

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Car runs perfect for a few miles. Then the valves will get very loud, but it does not lose power.. I can turn car off and wait about 15 minutes
and start it back up. It will be quite and running perfect. The I can drive it again and it starts doing the same thing. Please help.
At this point it's worth following VSTAR's recommendation for using a stethoscope; you can even use a very long screwdriver putting the handle to your ear. When this noise starts up, then at that point - Is the noise only present when you're driving the car or do you also hear it if you pull the car to the side of the road and without shutting the engine off, letting the engine idle. Also does the oil pressure light on the dash come on?
 
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