Mechanics

ENGINE KNOCKS WHEN COLD

1994 Honda Civic

Engine Mechanical problem
1994 Honda Civic 4 cyl Front Wheel Drive Manual 255000 miles

1994 honda civic 1.5 L. 255000 kms Bought new. Engine has been knocking when cold. After warmed up 5 minutes later all noise goes away and engine runs like a top. Never burns oil and lots of power still. Changed oil religiously every 6k kms. Checked valves and in perfect condition and perfect gapping. Any ideas? Piston slap in a Civic? Anyone?

THX
Avatar
Chinslip
February 2, 2009.



Hi there,

I would be checking the oil pressure on cold start up with a mechanical oil pressure gauge, this will show if its a pressure issue or a mechanical issue, start here.

Mark (mhpautos)

Mhpautos
Feb 2, 2009.
Oil pressure is good all around. How likely is it to have piston slap?

Tiny
Chinslip
Feb 4, 2009.
Hi there,

This is a possibility, or a cracked piston skirt or a gudgeon pin problem, it sounds as if you may have to pull it down to be sure, needless to say the knock is not good and if not rectified it may destroy the engine.

Mark (mhpautos)

Mhpautos
Feb 4, 2009.
Remember that the noise goes away once warmed up.

Tiny
Chinslip
Feb 4, 2009.
Hi there,

It well may be piston clearance problems, have you done a leak down test to see how the rings are preforming, often you really need to listen to the noise first hand, have you had a mechanic listen? Most engine knocks have a distinct sound and can be pin pointed with a trained ear,

Mark (mhpautos)

Mhpautos
Feb 4, 2009.