Chrysler Repair: 99 Concorde rattling sound from the engine, chrysler warranty, chrysler concorde

Question
QUESTION: Hi,

I have a '99 Chrysler Concorde. Bought it a year ago with 88k miles on it, now it's at 105k running with no problems till now. Two days ago I started hearing a rattling sound coming from the engine. After looking under the hood having my friend push the gas pedal I was able to determine the sound is getting from the left part of the engine block, possibly from the valves. Its frequency changes with the engine RPMs. I made an appointment with the Chrysler dealer, but there was no appointment date available till tomorrow so I decided to drive the car without pushing it too hard till then.
This morning on my way to work I heard the sound getting much louder and more "metallic" for about 1-2 secs and then it went away completely. Now it runs as smooth as ever. There were no warning lights all the time and except for the sound the car did not misbehave. A friend of mine suggested that it could be just dirty lifters that had finally shaken the dirt up... but somehow I feel there might be some maintenance needed. I still have an extended Chrysler warranty - in case of a major problem it would probably cover the fix, if it's maintenance it won't for sure :-(
Could you advise what should be done?
ANSWER: Hi Martin,
It will be difficult to ID the cause of the sound after the fact. But if you have the 2.7L V-6 that engine has been prone to have problems with build-up of crud in the crankcase so it might indeed have been a temporary loss of pressure to the valve adjusters on the left bank. I would be inclined to change the oil more frequently than the the recommended 7,500 mile intervals particularly if you do a lot of short trips and stop and go driving. Under more severe driving conditions changes at a 3,000 mile interval are recommended. That engine too uses three timing chains and the main chain has a tensioner which might have temporarily had low oil pressure which could lead to noise from that chain. With all those chains I can imagine any oil pressure issue could lead to noise. So if it has been more than 3,000 miles since you last changed oil that might be in order now. Make sure the oil is changed when the engine oil is warmed up. The 3.2L uses a timing belt and doesn't seem to have the same propensity as the 2.7L. You may get more info at a site like Allpar.com or Dodgegarage.com where folks with more experience with the 2.7L may have posted suggestions.
Roland

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QUESTION: Hi Roland,
Thank you for a very prompt answer.
I forgot to add - I have a 3.2L V6 engine - according to what I've read they are not that faulty as the 2.7L ones. I do change the oil every 3000 miles - still 500 miles left till the next one, but maybe I won't wait and do it right away. Another thing that I should have added is that the engine is probably burning the oil a bit. Ca. 200 miles after the last change I noticed it was a bit low and took it to the oil service for a free refill. There are no oil stains in my parking place, so I assume it is being burned.
Do you think this may be connected?

Answer
It is hard to say unless you had verified the level shortly after the last oil change. You might want to check the actual level of the oil at your regular parking place when the engine is cold so that all the oil has returned to the pan and thus get a good idea of how much oil usage you are experiencing. If you hear the noise again that would be a good time to check the oil pressure gauge for any signs that it might be low. Of course if there were accessive wear of the engine bearing surfaces that could cause noises and lower oil pressure but that would not seem to be the basis for an engine with only 88k miles.
So keep you eye on the level and the pressure reading until this has not occured again for a while.
Roland