Question, I have a loud knocking noise coming from my engine but it isn't continuous I'll hear it at start up once every minute or so until the car starts getting warm and when I shut the car off. Just a singular knock sounds as if it's coming from the back, recently changed the spark plugs a 1,000 miles ago, wondering if it could be that?
>using 87 octane garbage on a race enginr
>>27951024That's just a stock photo, I have a 4.6L V8
>>27951022A "knock" every once in awhile sounds more like a loose component or you left a socket somewhere and it's getting bounced around when its cold and not running as smoothly as when it warms up.
Piston slap or you got a rod bearing about to self yeet. Piston slap goes away once the piston warms up and expands, rod noise goes away after the oil pressure comes up immediately after initial start up. If you got a savvy ear you should be able to tell if the noise is crank shaft speed or cam speed, if it’s cam speed you got valve train issues but those do t usually go away once warmed up.
>>27951135i kneel
>>27951022that's Mopar, baby!
>>27951022Did you make sure the car has gas in it?
Measure the oil pressure. Oil pump might be dying.
>>27951022Is piston slap common for your engine?
>>27951022>>27951024>>27951029>>27951929It's probably the type of fuel you are running or the oil.New plugs means it's injecting the fuel better than it was before they went out. >>27951135>>27951938I don't think so.
Everybody seems to be missing >I'll hear it at start up once every minute or soIf that's an accurate statement then it's not a bearing or piston slap.
>>27951995yeah that sounds like maybe a loose piece of metalsome car companies have been having quality control problems with machining chips left in the oil galleries lately, maybe one came loose on you
>>27951939>New plugs>Injecting fuel better
>>27953035yes? spark injectors inject burning fuel into your manifold.
>>27951938>>27951135Piston slap isn't common I have a panther, I'm OP
>>27951995>>27952281OP hereThat's why I'm curious and stumped, because I saw engine knock videos, piston and valve and it sounds nothing like that, it does sound like something is banging but there is long periods in-between this sound
>>27951022Probably the exhaust manifold gaskets, they get thin and old with age and they are likely loose when your car is off the headers and block are cold. Then after several minutes of driving the noise goes away after heat from the headers expands the metal and it seats nice and flat against the block. The gasket is cheap itself but you have to unbolt your headers to install it.
