Marc Glasser

Noticed a loud knock coming from the engine that sounds like a rod knock or valve train issue and have been chasing down the source and finally noticed I left the throttle return spring off!!!

How bad is that for my engine? Never drove it like that and only gave it throttle once to see if the knock would increase volume or frequency with RPMS and it did...

In the process of re-assembling everything now, but has anyone ever heard of something like this? Broken or no throttle return spring = engine knock type sound? Or is it probably something else?

akdoggie

It's something else. Internal problem.

Marc Glasser

Yeah, I just put it back. Still doing it...

sounds like this...

and this when I put it into drive or reverse it changes tempo and gets a little quieter but still loud as heck.

Replaced: valve cover gaskets, intake manifold gaskets, EGR tube, and spark plugs. All wires are where they're supposed to be. Definitely feels like it's coming from the passenger side valvetrain and resonates throughout the whole intake and exhaust so kinda hard to pinpoint it exactly.

tcrote5516

Forget a wench in the valve cover?

But seriously, something is laying on a valve or was bent out of shape.

Holicori

Or accidentally drop a screw in a valve cover, intake or something?

Carcrazygts2

sounds like something drop and hit finger follower.

Marc Glasser

Hmm don't think it's the valve cover. Saw a lot of dirty oil but no foreign objects when I sealed em back up. All tools and nuts are accounted for as far as I know.

Blocked the ports while I did the job to make sure nothing crept in. Seems possible that some rubber or plastic from the gasket could have dropped down a port while I was taking off the intake and didn't realize. But would that be enough to bend something? Maybe if it was on it's way out already?

I thought maybe it could be a spark plug but the old one's all looked intact to me so I'm thinking there's a chance one of the new one's could have blown out or maybe some porcelain broke somehow? Feel like I would have noticed that.

either way, I guess I'm going fishing... unless there's another possibility?

Carcrazygts2

whatever is tapping will show wear. Use a stethoscope to pinpoint where the location might be on the right side.

akdoggie

I just listened to the audio, and was wondering if a lifter popped out and the tapping being the cam/arm making the double tap? Did you take or leave a lifter out? Sounds like it is right there. Not a lower problem, more an upper cylinder problem.