Got Knock ? I Do!!!

[boostmaster]

hi guys i went from 18 psi knock free to knocking your block off. i'm running a ta 49 with all the standard goodies jl 93 chip, tps set at .35v, static fuel pressure @ 40psi, 02's @ .870-900v @ wot. the knock counts go as high as 15* i can here it then disappears. the are also 2 things i'm concerned about 1: will a bad altenator cause knock, mines seems to be working some times and sometimes it does'nt. checked it on the sabre at work and it checked out fine but sometimes the light comes on dim and the car does'nt seem right. 2: i may also be getting some false knock from my torque convertor, seems to be some light but audible knocking coming from that area, yes the bolts are tight i checked and yes it is from the convertor area, had on the lift. HELP!!!!!

 

[Stephen Soulsby]

I can tell you when my alternator went bad it knocked very bad and ran terrible. I think it may be the coil isn't getting enough voltage to supply gull spark. Not to mention the fuel pump slows down when voltage drops.

 

[cool 84]

Yes, alternator will definately cause it. With my friend's T-type, with a fully charged battery and the alternator not putting out at all, it detonated horribly at 10psi. When my alternator went out on my way home one time at night, it would audibly knock at 3psi. You lose ignition voltage, injector, and fuel pump, all of which will make it knock. Even 12 volts isn't enough. It has to be above 13 to run right.

 

[Buick From Hell]

checked it on the sabre at work and it checked out fine but sometimes the light comes on dim

Sounds like just the voltage regulator. Mine acted this way after the car sat for a long time and it was the regulator. You can pull the regulator and get it checked for free at autozone (among others)

 

[cool 84]

The regulator is internal. Usually the whole alternator gets replaced. Believe it or not if the single wire that goes to the volt light is disconnected it won't charge. Also, make sure the belt isn't intermittently (sp) slipping.