Hello everyone. I have a 2000 Coupe with 32K miles on it. Upon cold start up, I get what sounds like a lifter not pumping up, for about 30 seconds, then it goes away. I can get it to go away immediately by speeding the engine up to about 1500 RPM and letting off. Is there an easy fix, like adding something to the oil?
Thanks for any and all replies. Tom Woodgeard - Sarasota, Florida

 

its verry common my 99 is the same way

 

Could be the well-known, but dreaded LS1 piston slap. My '01 does if for about a minute or so, after the initial fire-up.

 

valve train noise, likely a lifter(s) pumping up,by the symptoms you describe and as you speculate. Never worried me at all.
I have a pristine low mileage 05 Mercury Grand Marquis Ultimate that does the same thing. The difference is that it has so much cabin insulation that I have to be out of the car to hear it. Piston slap usually produces a heavier knock, not a ticking sound. The valve train and lifter noise is more likely to occur after the car sits for longer periods between uses . If mine sits for 2-3 days, it is more pronounced. It also seems to me that the plastic valve covers seem to transmit the sound more than metal covers on earlier Vettes I have owned, I have splash shields, and when I fire up my 350/350, "71 without the covers, it sounds like a thrashing machine. When I put the metal covers on, it sounds normal.

I would stick with the the recommended Mobil 1 or equivalent. If it gets real bad,or doesn't go away after a minute or so, I might try to isolate what may be a weak lifter and replace the offender.

Many of us Vette owners, me included, tend to be perfectionists and hyper-alert to sounds and feels from our babies. My dad had a machine shop, and we used to build dirt track racing engines. Made me real sensitive to deviant noises. Ruined me for life!


Dave

 

normal LS1 quirk.

 

my '04 has been doing this for 157K miles without any engine problems.

 

Thanks for all the replies....I wonder, is there a product to add to the oil to free up the lifter, or do I just not worry about it?
Thanks...Tom Woodgeard - Sarasota, Florida

 

If there was, there would be a lot of happy LS engine owners.

The time to start worrying is when it doesn't go away.

 

Mine does that except when I pre-lube with accusump. I don't pre-lube every time I start so I do hear it occasionally.

 

""GM death rattle " LOL--although GM says the piston slap won't hurt the engine--Just old school thinking makes me let it warm up and allow it to stop before driving--

 

If the noise is piston slap, oil selection can sometimes lessen it. What oil and filter are you running?

If it's a lifter bleeding down overnight, I've had good luck with Valve Medic in two cases using it according to the directions. Pour into oil filler, run ~200 miles, change oil. One case was my '02 Silverado that had noisy lifter(s) at startup, other case was a neighbor's 03 Z06 that had lifter tick at hot idle.

In both cases we then switched to Mobil-1 High Mileage 5W-30 instead of the regular M1 for the added zinc & phosphorous antiwear additive package. No more lifter noise.

My '01 LS1 had a nasty piston slap noise at cold startup since new. I tried different oils and ended up with Red Line 5W-30 as the quietest...can barely hear any slap even with the hood open.

 

I'm running Mobile 1 5W30 and the AC Delco 44 filter. I'll look in to the H-M Mobile 1......Thanks for all the help everyone!!

 

I'd run a bottle of Valve Medic through it, and then go with Red Line 5W-30 just to take the oil completely out of the equation though.

Good luck and let us know how it goes. Don't expect immediate results, put some miles on it and keep observing.

 

I hope you only have a noisy lifter. I have a 2001 and I had a lifter come apart. The needle bearings came apart an thus wipped out the cam.

 

Great point, but those make noise constantly in my experience...lifter bleed down is transient, and piston slap goes away at operating temp.

 

I firmly believe,IMHO, that pre-lubing is the best way to extend motor life. This is even more true in colder climates. Estimates as high as 80% of engine wear occurring upon cold start and warm up are common. Of course using and changing a good synthetic oil is equally critical.

A good pre-lube system goes a long way to reduce overall engine wear. I have seen pre-lubed motors easily go 300,000 miles with nominal bearing and ring wear.

 

That's what I'm talking about. Mine taps too at start up. Whenever I try to be a perfectionist, I end up with more problems. Just drive that sucker till it has real problem. Whether a Vette or a chevette. They are just cars. Mine is a daily driver with 103,000. I tune it, change the oil, all other regular maintenance and clean the hell out of it. I was never one to be a garage queen. I met a guy recently with the same vette as mine, a 2000 convertible, but his had 13,500 miles on it and his vette has been in and out of the shop many times, last time was to replace the computer. I told him the worst thing he could do is let a car sit. More problems arise from sitting than driving, in my humble opinion. Case and point I work with many people with beater cars for running back and forth to work and some guys put 100+ miles a day on them and they NEVER do any maintenance and there cars have 2-3&400,000 miles on them and they keep there nice cars home in the garage and guess what, those nice cars at home that they baby have issues for more often than the beaters..... Weird,but true.