My oily '01 which burns a quart every 1000 has been pinging since I bought it a year ago. I took it to the dealer and they charged me $44 (half-hour labor) and told me that it was cheap gas and nothing could be done. I always run premium.

I asked about the decarb procedure but was told that it would cost $250, and involved removing all the plugs, leaving the car overnight, etc., and the ping would come back in a month or two. They recommended flushing the fuel injectors for $140. This didn't make sense so I decided to pass and paid my $44. While I was there I picked up two cans of top end cleaner for $16.

Next I referred to the seemingly difficult to find but excellent tech tip on how to perform the decarb here:

http://www.corvetteforum.cc/techtips...=212&TopicID=1

I had a hard time keeping the engine running at the right speed with the PCV disconnected as it wanted to run at 2000 or 400 RPM. I ended up using a club to hold the throttle at 1500 RPM which I discovered was too high.

I poured in the cans and tried to stall the engine on the last can but it just swallowed it up and kept running so I had to run and kill it.

I let it sit overnight and fired it up the next morning.

The guy that said there would be a lot of smoke was understating. I had a complete and total smoke screen for 5 mins while I held it at 2000 RPM. I've never seen so much smoke out of a car. Should have taken a pic. It ran very rough during this time before clearing up.

After that I drove it and the ping was gone! Also, there is a noticeable improvement in performance.

So the moral is, if your C5 pings on premimum gas, decarb it!

 

Ive been trying to tell people for years about ping with an LS1 engine at 10.5:1 compression. AS the car gets older , or in your case eats oil on a regular basis.. the cylinders are going to see higher compression..
and with that cmes pre-ignition.. The car will carbon up again.. but with the GM engine cleaner.. the carbon is not completely gone from your car..but it will be in about 1000 miles.. the chemical is absorbed by the hardened carbon, and is safely burned off while you drive.. the smoke you saw initialy was the oil and the soft carbon of the last few months of driving.. You did good.
Wait until the C6 motors @10.9:1 compression start to see some carbon build up.. (all cars get carbon build up) and they live in a state where they can only get 91 octane... I can see down the road.. problems and dealership nightmares. Heads being pulled and double thick head gaskets.. and with that a loss of advertised HP.

 

thanks for sharing you experience and ET, thanks for the clarification as to why this works. i'll be sure to do the decarb when it's time for my next oil change. thanks again for the info.
Walter

 

Does this cleaning procedure harm the cats ?

 

No the cats are not harmed in this process

 

Assuming we can get high quality gas, wouldn't the increased compression add horsepower?

 

Is there a product that I can pour into the gas tank
that will perform the decarb while I drive ?

 

make sure you change the oil right after that. Maybe even twice. That is VERY important.

 

Berryman's B-12 carb/fuel injection treatment is a great, inexpensive fuel additive. I run it through all my cars on an annual basis, but primarily to clean the varnish off the fuel injectors. Secondarily it also helps erode some of the soft carbon buildup.

ET,

Are you saying that the amount of smoke you get on initial startup after letting things soak is mainly due to the soft carbon and oil in the cylinders, as opposed to the cleaner itself?

I've always wondered why I never got much smoke after doing this procedure.

Have a good one,
Mike

 

Very true, Evil. The 10.9 CR is too high for a street motor and the gas is not getting better with all the smog additives. With 91 octane the LS1 barely makes it.

 

Sunoco has a good 94 octane gas. It should be available pretty much everywhere. That might help some Forum members if they are only getting 91 or 92 octane.

 

No Sunoco out West. Does not comply with smog regs.

 

Not in TX either, Sun Oil is an East Coast Company.

Hey E-T, want start a de-carbon business? Sounds like it will be the wave of the future with all the Hi-comp engines being produced.

 

I think people could do alot better dumping their GMPP stock.. I have a feeling its going to take a big hit in the next three years.

 

You should have pulled into the street and acted like you were doing a massive burnout.

 

Another good product is BG44K fuel/oil additive and SeaFoam. I de-carbed with seafoam and my ping went away. My car only has 7000 miles.

 

BG44K is the best.Save the Wave.>George

 

FYI - I just went to my chevy dealer to purchase the GM top engine
cleaner and the guy behind the counter said that they make both a
pour can as well as a spray can. So now you can remove your airbridge
and just spray it in the throttle body instead of dumping it down your
intake with a funnel.

 

Here are some pics, if you need some!

http://forums.corvetteforum.com/showthread.php?t=910635