3100 SFI Engine Knock???

[97loudcut]

So I recently aquried an engine knock.

 

I have a 2 dr. 97 Cutlass and it runs phenominal.

 

I have noticed that when the engine is cold and first started up the engine has a slight knocking to it until the car warms up and then it goes away. I tried fixing it by adding some LUCAS oil treatment but I was a dummy and added 10w30 instead of 5w30 comletly ruining my whole purpose. Does anyone know what this knock is and how to fix this?

[jdcutty]

Yep, really cold, thick oil takes time to make it's way through the motor. How long has it been since you did an oil change?

[AWeb80]

Piston Slap

[ToroToro]

Lifter tick. The lifters get old and dont hold oil as well anymore, so after it's been sitting for awhile it takes some time for the lifters to pump back up.

 

Normal, and completely annoying. Mines probobly about 10X worse than yours too, if yours just started doing that.

[SigEpCutlass]

lifter tick is a recognized issue from GM in one of their TSB's. It's okay & you don't need to worry unless it does that when the engine is warm/hot.

[19Cutlass94]

yeah, like others said, dont worry about it.

 

 

BTW, are the lifters solid or hydualic (sp)? Just wondering because when I tear into my engine in the spring Im gonna replace em and hoping get rid of that annoying tick...(since mine still seems to do it a little bit when warm)

[DaveFromColorado]

they're all hydraulic lifters - if you had solid lifters, you'd have to adjust the valve lash manually before the tick would go away, no matter the tempature of weight of the oil.

 

--Dave.

[5speedz34]

Yeah, don't worry alot of our motors have piston slap of somekind.

[94CutlassSLCoupe]

It the transmission!!!! my car has done the noise from day 1 as does the 3.4 DOHC cutlass we have AND the 3800 Series II GP (97 so it has a 4t60e)...its front pump cavitation...its a TSB for all 4t60-e cars.

 

Piston slap is much louder than the noise i have and you're describing. Plus my noise (present on 4 cars my family owns) won't go away unless you drive it for a block, no matter how warm the engine is (meaning its the trans)

[chadz34]

It the transmission!!!! my car has done the noise from day 1 as does the 3.4 DOHC cutlass we have AND the 3800 Series II GP (97 so it has a 4t60e)...its front pump cavitation...its a TSB for all 4t60-e cars.

 

Piston slap is much louder than the noise i have and you're describing. Plus my noise (present on 4 cars my family owns) won't go away unless you drive it for a block, no matter how warm the engine is (meaning its the trans)

I also have that, is it normal?

[SigEpCutlass]

It the transmission!!!! my car has done the noise from day 1 as does the 3.4 DOHC cutlass we have AND the 3800 Series II GP (97 so it has a 4t60e)...its front pump cavitation...its a TSB for all 4t60-e cars.

 

Piston slap is much louder than the noise i have and you're describing. Plus my noise (present on 4 cars my family owns) won't go away unless you drive it for a block, no matter how warm the engine is (meaning its the trans)

 

wtf are you talking about? this is the first time i've ever heard of that.... :?

[ToroToro]

I've heard of it, but I know my car has nothing of the sort at 102K miles. I guess if it goes away without moving, it's the lifters. If you need to drive before it goes away its the front pump. :?

[Brian P]

if it were the transmission making that noise on all the cars, my car would have still made it after I swapped engines. It didn't. The most common form of this noise is the lifters. Some are "piston slap" and maybe some are the tranny. Anyone with solid knowledge of diagnosis should be able to tell them apart.

 

edit: My old tranny made a hell of an odd whining sound when the pump shaft started to fail. Such a common problem on these tranny's it's unreal.

[19Cutlass94]

There is a different sound for each one, if you know what your trying to listen to, and like Brian P, said, the most common noise is the lifters. Which can be fixed.