Engine knocking LOUD
#1
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Engine knocking LOUD
Took the car to the track last night and ran a couple of 11.60's.
Then I let my dad drive it [big mistake].
He missed a gear and pegged the rev limiter.
Well, now it knocks pretty loud.
It also makes a 'chirp' 'chirp' 'chirp' sound.
I am hoping that all I did [or he did] was blew a lifter and/or a push rod.
Could also have spun a bearing or threw a rod
I am thinking the chirping sound is the collapsed lifter and the knocking sound is the gas trapped in the cylinder not able to get out causing that cylinder to predetonate. I am hoping and praying this is all thats wrong. It will be a no brainer to fix and not cost much.
What do you guys think?
Then I let my dad drive it [big mistake].
He missed a gear and pegged the rev limiter.
Well, now it knocks pretty loud.
It also makes a 'chirp' 'chirp' 'chirp' sound.
I am hoping that all I did [or he did] was blew a lifter and/or a push rod.
Could also have spun a bearing or threw a rod
I am thinking the chirping sound is the collapsed lifter and the knocking sound is the gas trapped in the cylinder not able to get out causing that cylinder to predetonate. I am hoping and praying this is all thats wrong. It will be a no brainer to fix and not cost much.
What do you guys think?
#4
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Just got done fixing a loud knock on my car, 01 Z. Mine had a loud knock when I started it up one morning, took it to the dealership, under extended warranty, and it turns out that I had a bent rod hitting the piston skirt. niether the dealership or the warranty company could come up with an answer as to why it happened, some guesses were hydrolock, which they ruled out with just one bent rod as opposed to multiple bent rods, and a faulty fuel injector, but nobody knows for sure. Just a little food for thought is all. Hope it's nothing to serious, mine ended up costing the warranty company 4,200.00, most of it labor of course!
#5
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Since it hit the rev limiter, I'm pretty sure its a bent push rod. Are your push rods stock? I know the factory push rods come pretty weak in the sense that overreving causes bent push rods quite often. I would take something like a long screwdriver and hold it to the valve cover above each cylinder with the other end to your ear. (Trust me this works). You will then go from cylinder to cylinder to find out which one is bent. You may even have multiple bent rods (more than likely) but only one that is pretty bad. I would replace all since the rods that are slighly bent are weak and will bend at the next 6k rpm. Don't even worry about the expensive work to the harder-to-get-to stuff. Just do the push rods first. If that doesn't fix the problem, then move on to other parts.