knock (again)
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Team Owner
Joined: Apr 2001
Posts: 22,267
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From: Dallas TX
knock (again)
Backgroud: 11.55:1 CR, 2 brand new knock sensors, LT4 knock module.
If there is real knock, the computer should be picking it up, right? I don't care about flase knock as long as it's at least picking up real knock.
If there is real knock, the computer should be picking it up, right? I don't care about flase knock as long as it's at least picking up real knock.
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: knock (devons88vette)
i'm not really sure i have a problem.. i tried to get some race gas today to see if it goes away, but they were all out! :eek: :nonod:
I'm getting knock counts sometimes, but not when I hear a mettalic rattling noise, which i'm wondering if it isn't real knock the computer isn't picking up.
I'm getting knock counts sometimes, but not when I hear a mettalic rattling noise, which i'm wondering if it isn't real knock the computer isn't picking up.
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: knock (devons88vette)
I don't know. That's what i'm trying to figure out with mine. It's either something like the cover to the flexplate/torque converter rattling at a certain harmonic, or it's donation.
Mine is around 3500rpm
Mine is around 3500rpm
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Joined: May 2002
Posts: 63
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From: tyler tx
Re: knock (Glock'94)
i would guess it's false knock since it's isolated, it's so low in the power band, and you're not making a shift... but it just a guess. I'd ad a similar problem once my '93 TA. The motor mounts had deteriorated and let the engine drop. The headers hit the frame/body and the KS was picking it up.
If the datamaster isn't picking up knock through the sensors, then I wouldn't think you have knock. Does the engine feel like it's loosing power at that point or do you jnut notice the sound?
Sorry I can't lend any useful advise.
If the datamaster isn't picking up knock through the sensors, then I wouldn't think you have knock. Does the engine feel like it's loosing power at that point or do you jnut notice the sound?
Sorry I can't lend any useful advise.
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: knock (rguy)
oh, any advice is great :)
I don't feel loss of power when i hear the metallic rattle. The reason for wanting to get race gas is so i can be sure it's not knock. It'll also allow me to see if the knock datamaster IS picking up is false or not.
I don't feel loss of power when i hear the metallic rattle. The reason for wanting to get race gas is so i can be sure it's not knock. It'll also allow me to see if the knock datamaster IS picking up is false or not.
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: knock (Glock'94)
Glock,
Hey guy. You should NEVER really hear the knock. The sensor should pull the timing back before it ever becomes audible. Now if the knock is so bad that it exceed the parameters of max pull out then you will hear it.
Sounds to me that something is just rattling. I would try to find out what it is. Not sure on your car, but there are several heat shields on the L98s that could make the noise you describe. If the knock sensor is not pulling time at that point, then it is not knock.
How is the overall picture looking for your tuning. Get the BLMs straight and most of the knock out?
Let me know.
Hey guy. You should NEVER really hear the knock. The sensor should pull the timing back before it ever becomes audible. Now if the knock is so bad that it exceed the parameters of max pull out then you will hear it.
Sounds to me that something is just rattling. I would try to find out what it is. Not sure on your car, but there are several heat shields on the L98s that could make the noise you describe. If the knock sensor is not pulling time at that point, then it is not knock.
How is the overall picture looking for your tuning. Get the BLMs straight and most of the knock out?
Let me know.
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: knock (ski_dwn_it)
ski,
yes, it seems to be running very well besides that odd noise. I still haven't completely figured out why I'm getting a little knock. But, like I said, when I get some race gas I'll find out if that's false knock or something I need to work on. You've been a great help ski, thanks! Tuning is a never ending venture with these cars the second you start modifying them. :crazy:
yes, it seems to be running very well besides that odd noise. I still haven't completely figured out why I'm getting a little knock. But, like I said, when I get some race gas I'll find out if that's false knock or something I need to work on. You've been a great help ski, thanks! Tuning is a never ending venture with these cars the second you start modifying them. :crazy:
Former Vendor
Joined: Jun 2001
Posts: 7,204
Likes: 6
From: St Marys PA
Re: knock (Glock'94)
ski,
Tuning is a never ending venture with these cars the second you start modifying them. :crazy:
Tuning is a never ending venture with these cars the second you start modifying them. :crazy:
I would se if the car make the *noise* while sitting still and at that RPM. If so then you can put it up on a lift or secure it VERY good on jacks, etc and crawl under it and have a buddy rev it so you can see it. Or better yet, if you have friends like mine, send one of them under to look :lol:
My dust cover for the TC had a bolt or two stripped on it, so I just deleted it. It really serves no purpose. I just have to be careful when I have it on a lift and the engine is running. That flywheel could do some serious damage to the scalp! :eek:
Check all the heat shields too.
Do you have headers?
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: knock (ski_dwn_it)
yeah, i'm still thinking it's the dust cover .. because that's around where the noise is... and i can hear a little bit of a buzz when sitting still and revving it.
no header, just stock manifolds right now.
yeah, i'll check my heatshields.
no header, just stock manifolds right now.
yeah, i'll check my heatshields.
