3.5 Engine Knocking

[kyleo51]

I have a 2001 with the 3.5L V6, and just last weekend, i noticed a knocking in the engine! Dont' know what the deal is, had it to a few service shops, and none of them want to tear into the engine to find out what it is! Anyone have any similar problem or have an idea's. I've gotten so many possibilities, i could write a book. I've heard the wrist pin, the rod bearing, however i was told that if it was a rod bearing, that it would've done locked up by now, but i've also been told possible broken valve spring, lifting lever, main bearing, something in the valve train! Lots of possibilities! But no one knows for sure! Some think its coming from the bottom of the engine and some think it's on the top! No one really knows! Any Idea's i need some help, FAST!! Thanks

[kyleo51]

and if this ain't fixable, anyone know the cheapest way to get to get it fixed or know of a place to get another engine!

[GTP Dad]

Try this to find a used engine: cherry-auto.com or car-part.com. Cherry-auto offers warranties with all their engines and car-part.com will give you information on where to find an engine at a wrecking yard in your area.

As for the knock, it sounds like the folks you are listening to are really confused. A rod bearing can go for a long time before the bearing will totally fail or the rod break. As for the upper part of the engine if you dropped a valve it would be a heavy metal to metal knock and you would have significantly less power than before. If you punched a hole in the piston you would see or smell fuel in the oil. If it were a lifter it would sound like a rapid tick tick tick, rather than knock. Just a few possibilities.

[GMMerlin]

A bottom end noise will be a knock
A top end end noise will be a tick

When does it happen, cold, hot, idle, driving

[zephram22]

Originally Posted by kyleo51

I have a 2001 with the 3.5L V6, and just last weekend, i noticed a knocking in the engine! Dont' know what the deal is, had it to a few service shops, and none of them want to tear into the engine to find out what it is! Anyone have any similar problem or have an idea's. I've gotten so many possibilities, i could write a book. I've heard the wrist pin, the rod bearing, however i was told that if it was a rod bearing, that it would've done locked up by now, but i've also been told possible broken valve spring, lifting lever, main bearing, something in the valve train! Lots of possibilities! But no one knows for sure! Some think its coming from the bottom of the engine and some think it's on the top! No one really knows! Any Idea's i need some help, FAST!! Thanks

I had a knocking noise. I threw some 94 octane in and for the most part the knocking stopped. I've switched back to 87 sinces though, since 94 is still about 3.50 a gallon here.

[kyleo51]

Originally Posted by GMMerlin

A bottom end noise will be a knock
A top end end noise will be a tick

When does it happen, cold, hot, idle, driving

IT isn't as loud when it is cold, but when but it warms up, it gets louder! And it possibly could be a tick, i've never dealt with this stuff before and i'm not the mechanic type, i mean i can do maintenance and stuff to my car, but when it comes to engines i don't know much! I'm just taking it for what a guy i work with who is constantly rebuilding engines and works alot with cars, and my uncle who knows quite a bit about cars! I just found out today, the guy i work with, he figured that by how fast the ticking/knocking noise was, that is has to be in the valve train somewhere, cause he said if it was in the lower part, that is should be ticking/knocking a lot faster than what it is!! But i'm taking it in thursday to have it checked but until then any other ideas, and i'll post when i find out what it is, incase anyone else has this same problem! Thanks for the help guys!!

[kiway22]

Check the simple stuff first. Make sure you have the proper amont of oil in the engine. And maybe try a full tank of premium gas.