unknown engine noise
 

I just came back from a trip of about six hours driving. When I got into the city and back to normal driving speeds I heard a noise comming from the engine. Its comming from under the air box and it has a metallic shimmer to it. I thought it was somekind of flange or my alternator or something but I can't put my finger on what it is. The noise was never there before and I don't have the time or place to any repairs right now. What should I do...will it hurt the engine any more if I let it go for a bit? Also when I left for my trip, my output transmission seal went on me, there was oil everywhere under the car and some flew up onto the bumper and spoiler!..what luck

any advise would be great

thanx

I've been looking into a very similar noise, and the guys on this bb seem to agree that it could be the heat shield of the CAT, which is welded, but sometimes breaks and rattles against the exhaust ... around 1000rpm.

Good luck, and keep us posted.

Hi Bro , first dont drive the car until you get oil back into the trans.....you will burn up the syncros and the carrier bearings ,......I just rebuilt mine and that what happened.......... and i need more info on what type of noise your hearing .top of engine front or bottom ........rattle whine .........what?????? Stan

Under your airbox, you say. What year? Is it located on the front driver side? Above the alternator? When my hoses swelled from an oil/coolant mix, the main hose to the resevoir started contacting the alternator flywheel, and cut a hole in it. Trace your hoses to see if any are contacting any moving parts (alternator, fans, belts).

I have a 1984n/a. The airbox is on the drivers side, the noise seem to come from the top of the engine but I really can't pin point it. I'm not quite sure it is the cat heat sheild because the cat is on the other side of the engine compartment. What do I do. I'll look for the hoses but I don't have too many resources to do a detailed check for a while. Don't worry about the tranny, I changed the oil and fixed the seal.

I have a 951 with a similar noise. It was hard to isolate without a stethoscope. With the scope, we pinpointed it to a sticking lifter on no 4 exhaust. It makes a light ticking noise. I ran some top end oil through it and it seems to be dissapating. There also seems to be a heat shield rattle, very faint, but there at about 1-3k rpm. You can get a mechanics stethoscope at any auto parts store for about $10. I highly recommend it for occasions like this.

Dave951M