Well, it appears that my original post with the same title was deleted for some reason, so I'll try this again.

My 2000 SS with 18,000 miles is getting close to the end of the warranty time period. So, I took it to the dealer to see what they would say about a minor case of piston slap that I get before the engine is up to full operating temperature and only between 2100 and 2400 RPM's. The dealer's solution is to suck in GM Top Engine Cleaner through a vacuum line while the engine is running. Then they shut it down for 4 to 5 hours, then they run the car hard to blow out the loosened up carbon.
The idea is that the carbon on one side of the top of the piston causes the piston to be unbalanced. This aggrevates the situation of the piston vibrating around in the excessive bore to piston clearance before the engine warms up and the piston to bore clearance decreases.

My question is, has anyone else had the GM Top Engine Cleaner service done to their LS1 to reduce or eliminate piston slap and has it worked? Also, can you think of any negative effects (such as hydraulic lock, bent rods, etc) from such a service? I'm trying to decide whether to let the dealer try this or whether they may do more harm than good.

Thanks in advance for any or all suggestions or comments.

 

I have never heard of a dealer using the cleaner for PS.....prolly because it won't work. Be prepared to deal with such BS because i'm about 99% shure they will not fix the car unless the PS lasts all the time, but some have gotten lucky and got their car fixed. If any thing they might extend the warranty....like they did for me at about 6000mi but now I can hear the PS even when the motor is at full temp and has been run for awhile at 11500mi, needless to sat I have to make another trip back to the dealer From what i've read if they use the cleaner they are supposed to change the plugs and oil after they run it through the motor. And I hope the orginal post didn't get deleted because this is a "sencetive" subject with some people.....that would be pure BS

 

bttt

 

I have the "piston slap" sound in my car and i took it the dyno yesterday. As we were pulling it up the dyno one of the guys asked me about it and I told him I though it was the "LS1 piston slap" so many people have. He said no it's probably a valve issue(if I'm saying that right). These guys pretty much specialize in LS1's too. When I have the money I'm taking my car to them to check it out, it's out of warranty, I'll repost here once I have them look at it.