I have a `96 Cougar with the 3.8L V6. I am getting what sounds like
valvetrain noise from the number one cylinder. When the engine is cold
there is no noise, the car idles well, and it accelerates amazingly well
(or at least better than what you think a car with 217K miles should).
Once the engine reaches operating temp, a steady clacking noise that
changes tempo with engine speed comes up; it is audible from in the car,
and seems louder when I take my foot off the accelerator and let the car
coast. Under the hood the noise is constant. Also when the noise is
present, idle with the transmission in any gear is slower than when
cool, and the engine vibrates. Eventually idle drops to 500 rpm and
stays there with the engine shaking the car; my scan tool shows that
even at 500 rpm, the computer isn't trying to raise the idle speed at
all. Also when the engine is hot and that racket is going on, the car
loses a lot of power, just won't accelerate for crap, and slams hard on
the 1-2 shift. It feels like it takes twice the amount of accelerator to
get the car moving than it does when it's not rattling. If this is from
a sticky or collapsed lifter, could one problem lifter be causing all
I just bought the car from a guy that picked it up from an auction, so
ihave no clue about its service history. All i have done so far was a
complete tranny fluid and filter change (about 13 quarts of new fluid).
Any insight at all is appreciated!!!