gsx knocking on decel

[decateur]

I have a 95 gsx with a 1g swap i have a knock on decel and low idle, it sounds just like this.
YouTube - Eclipse Knocking
If any one can help that would be great. thanks.

 

[SmoochDarling]

Do you have your EGR disabled? Some people (with logs to prove it) say a functioning EGR valve can actually reduce knock as the unburnt exhaust helps reduce predetonation.

In your case I would think it could be a sensitive knock sensor picking up some vibrations as you deaccel…

Is your knock sensor leaking?

 

[haswesley]

I think you are asking about a knock that you can hear with your ears, and not the knock that the knock sensor picks up. So, it sounds like a rod is knocking. You can tell if its a rod by stepping on the gas and then releasing quickly and listen to the knock while the rpm's drop. If the knock is much louder while the rpm's are dropping, it is a rod knocking. You may only need new rod bearings. But, while your in there, I would suggest changing the main bearings, also. Continuing to drive with a rod knocking may result in throwing a rod (either through the side of the block of just breaking). Also, a worn rod bearing will be copper on the inside of the bearing.

 

[SmoochDarling]

Hmm I guess I had predetonation "knock" on my mind... +1 to rod knock.

 

[DSMopar]

Nice lawnmower ya got there... time to pull that thing... where'd you get it from?

 

[decateur]

Thanks to all that replied, I did not have a knock when I picked up the car It just started today the youtube vid is not my car I just used it as the sound is verry close to my sound. I hear no knock when accelerating only on decel. wouldnt a rod knock all the time?

I talked to the owner of the car in the video the knocking was broke flywheel bolts hitting the flywheel. So i will be looking into that to see if that is my prob.

 

[haswesley]

A rod doesn't always knock all the time. When under acceleration, the knock is usually quieter since the bearing is under pressure to turn the crankshaft. When you let off the gas, the bearing is no longer under the load and is allowed to slop between the crankshaft and rods. That's why rod knock is usually much louder when decelerating. A broken flywheel bolt is extremely rare. A broken flywheel bolt should make a sound ALL the time, not just decelerating. And, the noise should get faster as you increase the rpm's. Is this happening?

 

[decateur]

Ok all fixed when the last owner put the new flywheel on they must not of torqued the bolts they all were loose, the only thing stopping them was the clutch so now i can put in the ACT 2600 i have.