Engine Knocking loudly: need ideas
Thread Starter
Racer
Joined: Mar 2005
Posts: 362
Likes: 0
From: Simpsonville SC
Engine Knocking loudly: need ideas
My engine started knocking loudly the other day. I drove leausurely to work all was well. Started-up and sounded horrible when trying to go home. Oil pressure is perfect, no codes, sounds like a rod is trying to come through the block though. It seems like it gets better at certain rpm's when in gear, power seems ok but didn't hit gas hard. Checked all pulleys and for anything loose. Maybe a clutch problem? Any ideas would be great before I have to remove engine or drivetrain to troubleshoot.
Le Mans Master
Joined: Oct 2007
Posts: 6,149
Likes: 11
From: Greater Detroit Metro MI, when I'm not travelling.
My engine started knocking loudly the other day. I drove leausurely to work all was well. Started-up and sounded horrible when trying to go home. Oil pressure is perfect, no codes, sounds like a rod is trying to come through the block though. It seems like it gets better at certain rpm's when in gear, power seems ok but didn't hit gas hard. Checked all pulleys and for anything loose. Maybe a clutch problem? Any ideas would be great before I have to remove engine or drivetrain to troubleshoot.
1- Change the oil and inspect it carefully for metal shavings.
2- Purchase a mechanic's stethoscope and identify which cylinder that noise is coming from.
3- Pull the ignition wire or fuel injector plug from that cylinder and see if the noise quiets down. If it does, you've found your problem cylinder.
4- Run a compression test. If one cylinder is down, run a leadkdown test to figure out where the compression is being lost.
5- Start figuring out where I want the engine rebuilt.
Is your car modded?
Corvette Stories
The Best of Corvette for Corvette Enthusiasts
150 hp to 1,250 hp: Every Corvette Generation Compared by the Specs That Matter
Joe Kucinski
8 Coolest Corvette Pace Cars (and Replicas) of All Time
Verdad Gallardo
Top 10 Corvette Engines RANKED by Peak Torque (70+ Years of Muscle!)
Joe Kucinski
Corvette ZR1X Will Be Pacing the Indy 500, And Could Probably Race, Too!
Verdad Gallardo
Top 10 Corvettes Coming to Mecum Indy 2026!
Brett Foote
Top 10 C9 Corvette MUST-HAVES to Fix These C8 Generation Flaws!
Michael S. Palmer
10 Revolutionary 'Corvette Firsts' Most People Don't Know
Joe Kucinski
5 Reasons to Upgrade to an LS6-Powered Corvette; 5 Reasons to Stay LT2
Michael S. Palmer
2027 Corvette vs The World: Every C8 vs Its Closest Competitor
Joe Kucinski
Le Mans Master
Joined: Oct 2007
Posts: 6,149
Likes: 11
From: Greater Detroit Metro MI, when I'm not travelling.
Might be valvetrain related too... Bent pushrod, bent valve... Again, get the stethoscope and start troubleshooting. If it was my car I'd be posting compression test results by now and calling up some shops for price quotes...
Drifting
Joined: Sep 2008
Posts: 1,630
Likes: 3
From: Aiea Hi.
