My car is a very stock 93. I was checking around engine, looking for boost leaks. The car seemed to be running fine at the time. I happen to notice some aire coming out from the airbox out the bottom right side (when looking at it from the front of the car). There is a hose with a check valve that should be there. This is near the stock intercooler and ast. My hose is missing (took it into shop one time and it is no longer there) so that is why I noticed the air.

Being the brillian mechanic that I am, i put my hand over the leak and revved the engine. One the third rev, the engine made a "pop". Not an apex seal going, but something else popped. Now the car make a weird sound that is directly related to speed and load of the engine.

The attached picture is where the noise is coming from. Under boost and idle, the car sounds and runs fine. Under light load from above ~2400 rpm to maybe ~4000 or so, a noise comes out of the hose that I circled. It sounds similar to a fartcan on a civic. I thought it was the airpump was the culprit, but I am not certain.

I normally drive with all airbox connections in place. I took them apart to figure out where the noise is coming from.

 

The hose you have marked is the discharge from your air pump and it will make the infamous "moo" sound when it is disconnected from the airbox. You can do a search for "moo" or air pump or reconnect it to the airbox and it will be gone.

 

Double post.......................

 

moo! Yeah, I guess I broke something in the airbox. I disconnected the plug on the airpump and the noise is gone. One of the few parts on my car that is not stock is the catalytic converter. It lacks the air line going in so I don't think it will hurt anything with the pump unplugged.

 

Hook that hose back up, retard

Ron should have a few air boxes laying around at the shop.

Or...... I know someone who has a pettit cold air intake that he'll sell for $50.

 

Do you mean the hose the shop lost? And I fixed the airbox. The pcv filter cover popped off.

I'll pick up that CAI for $50 on friday of next week. I will be by the shop.