2003 Mitsubishi Eclipse HEAVY RAPPING NOISE

SEANRANEY

MEMBER
2003 MITSUBISHI ECLIPSE
6 CYL
2WD
MANUAL
85,000 MILES

WHEN I START IT WHEN ITS COLD THE MOTOR SOUNDS LIKE ONE GEAR IS SITTING STILL AN ONE IS GRINDING OFF THAT GEAR BUT THEYRE NOT GEARS ITS COMING FROM MY VALVES IN THE BACK SET SOMETIMES IT GOES AWAY WHEN IT WARMS UP IT ALSO GOES AWAY WHEN I GET THE RPM'S OVER 2-2500 BUT LATELY ITS BEEN A PAIN AN DOESNT GO AWAY AT ALL I WAS TOLD MAYBE A VALVE WAS STICKING AN I USED NUMERUS FLUIDS AN TEATMENTS BUT NOTHING SEEMS TO WORK JUST WANTED TO NO YOUR SOLUTON BEFORE I GO SPENDING STUPID AMOUNTS OF MONEY AGAIN

1 Reply

TYLER3G

MEMBER
17 POSTS

A deep rapping noise from the engine is usually "rod knock, " a condition brought on by extreme bearing wear or damage. If the rod bearings are worn or loose enough to make a dull, hammering noise, you're driving on borrowed time. Sooner or later one of the bearings will fail, and when it does one of two things will happen: the bearing will seize and lock up the engine, or it will attempt to seize and break a rod. Either way your engine will suffer major damage and have to be rebuilt or replaced.

Bearing noise is not unusual in high mileage engines as well as those that have been neglected and have not had the oil and filter changed regularly. It can also be caused by low oil pressure, using too light a viscosity oil, oil breakdown, dirty oil or dirt in the crankcase, excessive blowby from worn rings and/or cylinders (gasoline dilutes and thins the oil), incorrect engine assembly (bearings too loose), loose or broken connecting rod bolts, or abusive driving.

Bearing wear can be checked by dropping the oil pan and inspecting the rod and main bearings. If the bearings are badly worn, damaged or loose, replacing the bearings may buy you some time. But if the bearings are badly worn or damaged, the crankshaft will probably have to be resurfaced -- which means a complete engine overhaul or replacing the engine is the vehicle is worth the expense.