horrible knock
#1
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Car: 98 z28
Engine: ls1
Transmission: t56
Axle/Gears: soon to be 3.73's
horrible knock
I have just recently finished my 350 tbi swap but not sure about a few things. I bought the car with a 350 in it. I assumed the car was given a new esc module and new knock sensor becasue it won't run without those. For some reason, after i got the chip tuned by Kevin91z, it still knocks like hell. what could be the problem? knock gone bad, just an overall problem with the engine? any help would be appreciated
thanks
brandon
thanks
brandon
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Car: 91 Camaro RS Convertible
Engine: 305 TBI
Transmission: 5-Speed
Axle/Gears: 3.42
The exhaust leak could definitely be causing it, if its loud enough. I would never assume that the knock sensor/ESC were replaced with 350 ones, the car would run with that, it would just detect false knock more often I think, and maybe not detect actual knock some of the time, due to different frequencies.
If this guy tuned your PROM and now it's knocking, make it his problem.
If this guy tuned your PROM and now it's knocking, make it his problem.
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Car: 98 z28
Engine: ls1
Transmission: t56
Axle/Gears: soon to be 3.73's
no it knocked before and i had hoped the tune would take it out. He is the one to tune every third gen in so cal so i doubt it was him. i am going to take out the exhaust manifolds and tighten up the air tubes and hope that will cure it. I know the engine shop that put the engine in put gaskets on the manifolds and from what i've heard that's not right. There supposed to match right to the heads right?
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Car: 88 Camaro SC
Engine: SFI'd 350
Transmission: TKO 500
Axle/Gears: 9-bolt w/ 3.23's
When does teh knock happen? Is it a metallic 'ping' under load, a metallic hammering sound at all loads at certain RPMs, or just all the time?
#6
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Car: 98 z28
Engine: ls1
Transmission: t56
Axle/Gears: soon to be 3.73's
It sounds more like a rattle after putting some gas into at any rpm, cruising there is no knock. When i get into it it sounds horrible. It's gets worse as i shift into a higher gear
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Car: '90 RS
Engine: 377 LSX
Transmission: Magnum T56
What is your base timing set at? How many chips did he burn for you and did he have access to your car when doing so? I would check to see that you have the 350 KS and ESC module.
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#8
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Car: 98 z28
Engine: ls1
Transmission: t56
Axle/Gears: soon to be 3.73's
Yeah he drove it, took numbers, and again and again until we got the least amount of knock, best air fuel ratio and so on. I talked to him and said it could be something in my valvetrain causing false knock. I was also told that the 350 and 305 knock sensor are the same part. I am not sure about the esc though. How can I check?
thanks
thanks
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Car: 88 Trans am
Engine: high comp vette engine.
Transmission: 700r4
Axle/Gears: 308
u know my car has a knock \ tap from the bottom of the engine and i dont even think i have a knock sensor i have a 88 t\a and swapped in a 350 tbi. Do i have a knock sensor and if i do where is it?
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Car: 88 Trans am
Engine: high comp vette engine.
Transmission: 700r4
Axle/Gears: 308
what does it look like what color is it like a little round thing with like a dawn liquid soap squirer for the conector.
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Car: '02 Z06
Engine: L33 5.7
Transmission: T56
Axle/Gears: Stock IRS
sounds right, maybe 1.5" diameter, single wire plugged into it, its in the center of the side of the block near the oil pan.
#16
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Car: 98 z28
Engine: ls1
Transmission: t56
Axle/Gears: soon to be 3.73's
i fixed the passenger side exhaust leak so today i will do the other side. hopefully my knock will go away then. if not i will change out the knock
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Car: 98 z28
Engine: ls1
Transmission: t56
Axle/Gears: soon to be 3.73's
The passenger side was real loose, i really used just a socket to remove them, the socket driver wouldn't ratchet back they were so loose. Hopefully this will cure it.
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Car: Red on Red 89 RS
Engine: LO3 305 TBI
Transmission: TH-700R4
Axle/Gears: 10-bolt / 2.73
I had the same problem on my stock LO3... now I run 93 octane and it's gone... I guess I was pinging from massive amounts of carbon built up...
#21
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Car: 98 z28
Engine: ls1
Transmission: t56
Axle/Gears: soon to be 3.73's
i didn't get to the driver side yet. I had the engine rebuilt two years ago. I have only run 91 since i bought it. I know that's not the problem. Hopefully tonight will tell.
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