Broken Air Filter Discovered

[RH77]

About 5000 miles (3 months) ago, I changed out the air filter (got rid of the failing K&N).

It's a canister-type similar to this:



The basic replacement didn't fit snugly, so a hose clamp was attached to the intake coupling. Some lithium grease was applied to arrest any possible dust leakage. All was for naught, since apparently the hose clamp was too tight.

The hard plastic coupling broke, allowing unfiltered air into the engine. I discovered it since air intake temps were around 140F+, so something was up.

Now we have a problem. There's dust in the intake hose, and the break wasn't clean. A 1 cm x 3 cm shard of hard plastic is missing.

I cleaned the hose and sprayed the throttle body and intake as best as possible with carb cleaner and seafoam -- then changed the oil/filter and installed a higher quality air filter (with a slightly snug clamp).

The Question:
The intake hose was mildly dusty. How bad is this for the engine?

The mystery plastic piece: I've had redline runups to clean the SeaFoam through, so the piece would have had to have either made it upstream or fallen harmlessly to the ground. What would happen if this gets drawn into the combustion chamber (dare I ask)?

It runs great. So far.

All of this because of a precaution to prevent exactly what happened. Yeah.

RH77

[Johnny Mullet]

Now that you found it, whatever dirt is left in the hose would be minimal compared to the amount of dirt you already sucked through the engine. Good thing you changed the oil and got the air filter taken care of now! Just clean it the best you can and run it. The air filter will pick up the rest if any comes loose, just check it more often.

If the plastic piece somehow made it into the combustion chamber, it would have melted and been shot out the exhaust causing no damage. If it did not make it to the combustion chamber, it could be lodged somewhere in the intake manifold or stuck in an intake port. Worst case scenario is that it could cause a valve to stick, but the heat from combustion would melt the plastic anyway.

I would not worry about it if it were mine.

[RH77]

Originally Posted by Johnny Mullet

I would not worry about it if it were mine.

Thanks man. I was hoping that it wasn't a huge deal. I'm slowly learning to wrench on this car myself. Having a professional assessment is really a comfort.

Seriously -- we're lucky to have you here

Best FE to you and your Metro...

RH77