Hey All,

When I start up cold, after about 20 seconds there is a very noticeable ticking / clicking that varies with engine speed. This continues, constantly, until oil temp gets over 130 (sometimes longer) while I let it sit warming up. Clicking disappears at full operating temp (oil temp ~180) Not sure how long it has been doing this since I just bought it used about 1.5k miles ago.

Car is a 2002 coupe, 50K miles, stock.

 

Sounds like you may have a bad lifter.

 

Welcome to the small block chevy. Low ticking noise at start up is normal util there is enough oil circulated. The only why to eliminate this is to add an accu-sump to cirulate oil BEFORE you start the engine

Still may want to check your lifters.

 

What oil filter are you running? I had this problem with the more restrictive flowing filters like the UPF44 Ultra-Guard Gold. When I changed to a less restrictive filter the problem went away.

 

I just changed oil last night - was an AC/Delco on there, now there's a K&N. not sure how those filters flow, but this morning it was still ticking like a bomb until the oil temp came up. I have MajorGuard protection so think I'll take it in - thanks for the responses

 

I have an 02 as well. Based on your description mine has the exact same sounds. Does yours do it on every (cold) startup? Mine only seems to do it every now and then. Mine has 60k on the clock.

I always use M1 5w30, and ACDelco filter, pf46

 

K&N is one of the best flowing filters out there, so that would eliminate that theory. I would be interested to hear what they find, my 02 did it as well, but now I have changed a few things including the lifters. I have Morel lifters now and they tick for about a minute starting 30 seconds after startup, but all the Morels seem to do this.

 

It could also be piston slap...especially since it does it when cold.

 

From your description, I have EXACTLY the same sound and results on my '02. At first I thought it was the extensively discussed "piston slap" issue. However, being the car didn't do it before, I'm thinking it's a lifter issue. As in your case, the noise completely disappears when the engine reaches ~130+ degrees. I didn't notice the noise until a short while after switching to a K&N oil filter, however, switching back to the AC Delco filter made no audible difference. I don't think the K&N was the reason, just coincidental timing.

I figure I'll leave it alone until I do a H/C upgrade, when new lifters will be installed.

 

I thought it could be piston slap also (had that on a 97 trans am) but that would disappear when coolant temp came up, maybe after 3 minutes, and was really only noticeable when driving if the revs went over 2500 or so and it was still cold. The vette sound continues for a lot longer, and can be heard at idle.

Got the appointment at the dealer for Wednesday am - I'll let you know...

 

Okay so, the tech at the dealer hears the noise too and checked if there was lifter leak-down (amongst other things). Apparently there is not, but to progress to the next step, the dealership has to tear into the engine more. Since I have MajorGuard warranty protection a representative from GMPP has to come out and take a look before they'll authorize more work. 48 hour turn-around on the GMPP guy means I won't have more info until Thursday, but I'll keep you posted...

BTW, the dealer had heartburn over me using a K&N oil filter instead of the AC Delco, so they did an oil change (which I may have to pay for) as the first step. They said they've had problems with drain-back on some oil filters. I guess a word to the wise is to use stock replacement parts if you're still under warranty.

 

If they try to pin it on you, tell them to prove to you the filter cause the xxxx failure. Read up on this and arm yourself. *Most* dealers will try and screw you at every turn.

http://www.semasan.com/Main/Main.aspx?ID=60128

 

That's my thoughts too. Why would it be quiet for a minute right after startup and then get noisy if it was a bad lifter? IMO, there are all kinds of things going on as the motor warms up, and the piston skirt to cylinder wall clearance must increase some during the warm-up period ... hence the "cold piston slap" issue.

My 2002 Z06 does it also. Ticks for the first 3 minutes after a cold start up and then gets quiet after some warm-up. It takes it about a full minute after startup to start ticking, so I don't think it's a lifter. If it was a lifter it would tick the second it was started.

Also, I've seen a few threads on the other site where the lifter body clearance increases with time or was just sloppy from the factory, and that can cause ticking even when the engine is warmed up.

 

Where are you located at? (filling in profile will help).

Exactly what is the GM rep gonna look at that the mechanic can't see right now? (rhetorical question). I would be really loathe to have the dealer handle this, but I guess you dont have that warranty for nothing. My own experiences with dealers is just traumatic, but I will spare you the sob story.

If money isn't too tight, I would pay someone with LS1 experience that you trust to do this. On the other hand, this is the perfect excuse to do a heads/cam upgrade, as that is all but gauranteed to cure it.

Look on my web page to see my failed lifter. the back passenger side lifter (#8 intake) is a usual suspect, because it tends to get a little less oil than the others.

So hopefully they have already pulle the valve covers and inspected the pushrods, rockers and valves. Next step would be to pull the heads and check the lifters and plastic (sic!) lifter guides. Depending what they find there, they may or not need to pull the cam also.

If you are anywhere near the mid-atlantic let me know, I would be glad to help or point you in a good direction.

Oh, the pictures of the failed lifter and the wear on the cam lobe are on the "h/c tear-down" page off the nav menu.

Hope that helps... Good Luck!

 

My 02 Z06 has always done it. As stated above, maybe it comes with small block Chevy's. Let us know what you find out.

My money says the GMPP guy will say it's normal.

 

Quite a difference in noise between a bad lifter and piston slap. The dealer would have to keep it overnight and start it when cold to hear piston slap. A bad lifter will usually make the noise when it loses oil pressure hot or cold. So when you first start the engine and the oil pressure is low you will hear the lifter. As you know the cam is turniing half the speed of the crank so the piston slap sound will be twice the speed of the lifter. Good luck dealing with these wonderful GM service and warranty types, I feel for you. BTW my 02 has piston slap.

Rick

 

I checked at work on my dealer connect site (mechanic shop) and there was a recall about noise lifters on 02-03 vettes that has a oil pump O-ring problem with is sucking air up in the pump. You might want to check that since i was having the same issues and i repaced the pump with a high volume pump and changed the oil and lifter noise fixed. Also if the lifters were ever removed the oil hole on each lifter needs to go in the direction of on coming flow of oil.. Thats if you removed the lifters before..Seems there is a pocket of air that builds up by the oil hole if they are put in wrong.. Just some info..

 

I have a similar noise when cold and isolated it to noisy injectors using an auto stethoscope. They quiet down when warmed.

 

I keep reading about this and have a question. With pistons CNC machined exactly alike and bore diameters exactly the same, why is it that only one piston slaps instead of all eight of them?

 

My '02 is noisy for about 10 seconds, 33500 miles. My wifes '06 Impala was making a ticking noise and when I complained to the dealer they told me it is noisy fuel injectors. Sounds just like a lifter. Good Luck!