Blue Puffs at
May indicate damaged valve seals.
The smoke, which in most cases disappears after a few seconds, comes from
motor oil that has seeped past the valve seals and into the combustion
chamber when the engine is turned off. This is more common in older
There's no cause for immediate alarm.
However, since you are burning oil, make sure that the engine oil is
filled to the proper level. Problems may occur, however, if a lot of oil
seeps into the combustion chamber. This can damage spark plugs and reduce
Blue Plumes when
The piston rings that seal the oil out
of the combustion chamber may be old, perhaps to the point that the piston
cylinder walls have been scratched and scarred. The problem is most
evident when the engine has been pushing hard and then decelerates.
There is little reason to worry unless
spark plugs are fouling or if the oil level is not checked regularly.
In most cases, fuel-related problems
will cause black smoke to puff from the tailpipe. With today's
sophisticated fuel-injection systems, you'd be hard pressed to find this
problem, but it does happen.
A certified technician should be
consulted if the engine is producing an excessive amount of black smoke.
For an engine to remain healthy, it needs a constant, correct mixture of
air and fuel.
White Vapors at
When first started,
every engine will emit some white vapors that quickly disappear,
especially in cold weather. These vapors are caused by condensation in the
exhaust system and are perfectly normal.
Blue & White
This may indicate a blown head gasket,
a fairly serious problem. If there is a problem with the head gasket, the
engine will run rough, if at all, and antifreeze and/or oil will reach the
combustion chamber. Antifreeze and water will cause white smoke. Oil will
result in blue smoke.
A sure sign that there is a problem is
if oil is in the water, or water in the oil. As in any case with heavy
smoke, a certified technician should immediately check your car to help
avoid costly repairs.
noise only while decelerating at any or all speeds is most likely caused by bad
pinion bearings or loose pinion bearing preload, and almost never by bad ring
and pinion gears.
howl or whine during acceleration over a small or large speed range is usually
caused by worn ring and pinion gears or improper gear set up.
or whirring at speeds over about 20 mph can be caused by worn carrier bearings.
The noise may change while turning.
clunking every few feet may indicate broken ring or pinion gears.
or clunking only on corners can be caused by broken spider gears, lack of
sufficient positraction lubrication, or worn positraction clutches.
while turning may indicate bad wheel bearings.
steady vibration that increases with the vehicle’s speed can be caused by worn
u-joints or an out of balance driveshaft.
only when starting to move or getting on and off the gas might be loose yokes,
bad u-joints or worn transfer case or transmission parts