TLUZLS1

iTrader: (6)

Every time I start up my car when it's cold and I let it warm up, at about ~100 degrees there is a really loud slapping/tapping/knocking (however you wanna describe it) and you can even hear it with the windows up and radio on. It lasts for only about 20 seconds then goes away and the rate of tapping will increase with rpms. It is coming from the driver's side of the engine. I think it might be a lifter. Im not too concerned with it since it goes away pretty quickly and doesn't affect performance. It has been going on since the summer. I changed from Mobil 1 0w-40 to Amsoil 5w-30 to see if there was a difference but there was none. I even made a couple passes at the track last night and everything is still ok. Does anybody have any ideas and is this anything to really worry about? Thanks.

CAMAROZ28SS

iTrader: (5)

it seems like there are alot of cars that do that. my car is loud in the same spot. i guess alot of people call it lifter slap. its like a ticking.

formula87

iTrader: (2)

same here........... It has been doing it since 8 - 10.000 miles has 36k on it now hasn't gotten better or worse. It has been refered to as cold start knock piston slap ect. it is just an annoying noise I may see if I can get it on vid and post it

99HorseSlayer

iTrader: (1)

its been posted before vid wise, piston slap happens just be patient and let the car warm up it'll go away

and to answer the op its nothing to worry about they all do it if its cold enough just let it warm up

Gregory

iTrader: (4)

I once had that problem in a car of mine with 60k+ miles. I used that auto parts store engine cleaner for $1.50 just before I changed the oil and everything was fine afterward.

Grimlock

iTrader: (5)

Mine sounds like a sewing machine.

CAMAROZ28SS

iTrader: (5)

hahah same here. the ford guys i know all are like OMG your engines so loud whenever i start it.

TLUZLS1

iTrader: (6)

Ok thanks guys, I just needed some reassurance. I didn't think it was piston slap just because it just recently started doing it out of nowhere, but guess it sounds like it's no big deal.

angel71rs

You might be right about it being a lifter. Used to be that regular flat tappet style lifters would sometimes have the internal workings get gummed up. The use of Rislone was typically the thing to try and free things up. Since hyd rollers have the same type of internal workings, same thing could happen, but is probably not nearly as common with todays better oils.

Did a google search and seems they still make the stuff:

http://www.autobarn.net/ch100-qr.html

LS1Silverado05

iTrader: (41)

My car made exactly the noise you describe. I was hoping it was maybe a bent pushrod, but its not, so I am puting new lifters in along with my cam swap. However, the lifters that came out seemed to be in fine shape unless the internals were gummy, but I doubt it the rest of the motor was really clean. I guess Im saying, just live with it.

Dex

iTrader: (5)

Same here i've had alot of people tell me there is something wrong with my engine i just smile and keep going

Grimlock

iTrader: (5)

Tell them it's a new brand of hybrid techchlorabate lifter set that sets off minute explosions to raise the ratio 1/1000 to where our cars perform better with the optimum pydanomide tune with the latest software not available to the public.

TLUZLS1

iTrader: (6)

Cool thanks man, that sounds like it might be the solution. I'll keep my eye open for that stuff.