So I have a '99 accord LX coupe, that was running fine up until a few days ago when I changed the spark plugs just for preventative maintenance. As soon as I started up the engine afterwards, it made a noticeable "ticking" that sounded like valve lash. It didn't do this before I changed the plugs. So my brother adjusted the valves for me, and it didn't help at all. Yesterday I took it to a reputable honda mechanic to have it redone and it still hasn't changed. So I took it by a honda dealer and they told me it sounds like piston slap, and the cheapest way to get rid of it is to get a new engine.

What the hell? All I did was change the plugs. I tried putting the old plugs back in and that didn't help. It seems like more than a coincidence that it started immediately after changing the plugs. Is there anything I could have done to cause this?

 

unless you dropped something down into the cyl through an open plug hole, it's more likely that you just never noticed it before.

 

You MAY have broke loose some carbon within the combustion chamber. It normally flushes out the exhaust with the first start-up; but sometimes it lodges on top of the piston. If it lands in an area with tight clearances with the head, you can get not only a tick - but a knock as well.
Before you go all ^%&^$# over this; I'd suggest grabbing a 2' length of 3/4" heater hose and use it as a stethescope. Remember:
Injectors can tick as well as
The Exhaust can tick (particularly at the manifold.
The hose can help determine which.

If you need it, I'll give you the treatment for carbon buildup.

P

 

i've had 2 people listen to it with a stethoscope and its definitely coming from the bottom end, not the top, so we know its not valve lash. Do you think running seafoam through it would help? I've never done it on this car but I've done it on 2 others and it helped them both run smoother.

 

I would not recommend seafoam for your particular problem, however a good product to try for you situation would be lucas oil stabilizer, it sticks to internal engine components and prevents many tics and tocks. just drain part of the oil and pour in.

 

I wouldn't suggest anything until such time as you come back with the results of an Oil Pressure test. Mechanic In'na Can isn't the route to take and seldom works with worn components. in most cases:
Main bearings sound like a dull rythmic thud
Rod bearings sound like an audible knock during light loads and when feathering the throttle.
Piston Pins sound like faint double knocks as the piston changes direction
A collapsed piston skirt sounds like a chirping sound which diminishes as the engine heats up.

P

 

my 02 accord has the same problem.It's piston slap. mine sounds like a diesel.nothing you can really do about it,unless you rebuild your bottem end or just change the motor.at the dealer they replace the short block.couldn't do mine because i had no records of oil changes i do them myself.stupid on my part. but it sill runs I just change the oil more often,and eventually will change the motor.basically your piston skirts are scrapping the cylinder walls.i've seen engines with this problem on tl's and mdx's. the cylinder walls were scored.