Greeting Everyone, I'm new here and recently have been reading various parts of this forum. I noticed the hot topic here is Knock Retard ~ no pun intended.

I have not read anything about the glowing carbon particals in everyones combustion chamber, so here is a quick, cheap and easy way to give the inside of your engine a bath.
There are many ways and treatments available, but the most effective one I've ever used is GM'* "Top Engine Cleaner". Get it from your local GM dealership ~ costs around $10.

To use: Start your engines! Find an intake manifold vacuum hose (ex. fuel pressure regulator hose on the fuel rail). Raise the idle slightly to avoid stalling. Put the vacuum hose into the can of top engine cleaner and let the engine draw in the entire contents of the can.

Immediatly turn off the engine and let the cleaner soak in for a minimum of a half hour. If you can let it sit for 2 hours or more, you'll be doing yourself a favor, and an overnight soak would reap the best results.
When your ready to start the engine, make sure your not in a garage! Start, raise the RPM'*, and blow all that pesky garbage out. Enjoy the white billowing smoke that follows and pray for the ozone layer while your there.
This will clean the intake, valves, pistons....

Don't forget to service your throttle plates, esp if your pedal gas pedal sticks a little (happens more than you may think). And the IAC restricts with build up too. Might as well clean your EGR pintle while your in the mood.

Top engine cleaner also works great for cleaning injector fuel deposits. Use 10% cleaner and the rest gas on the newer multi tech fuel injectors. This is a max mixture and anymore will cause a stall and no restart until removed and system cleared. If you do clean your injectors, remove the fuel pump relay or unplug the pump and block off the fuel pressure regulator when cleaning.

I have seen decent performance gains after servicing injectors. This is a good idea for those of you with higher mileage/ older cars.


Good Luck

Sea Foam does this too

Welcome aboard Speeeeedy, many have used the GM top end cleaner or Seafoam as an alternative and we have seen some rather good results. Always a good reminder on the carbon deposits.

yeah i did mine last month lots of smoke and a better idle and throttle response did nothing for KR

FYI, GM No longer carries the Top Engine Cleaner as we used to know it.

The new stuff is called Upper Engine and Fuel Injector Cleaner part #88861802 and most of the techs in the local area think it doesn't work as well as the old stuff.

I picked some up and will tell you...I agree with the techs.

well here in canada iits call combustion chamber cleaner come in spray (part no 993026 ) or liquid call combustion chamber conditionner (part no 992872 )

Not suprised to hear it is no longer available. I knew it was not allowed in CA, and oh yea that stuff is wicked! I better hold on to what I have left like liquid gold.
I

wow do we have something in canada that the us don t the GM top engine clean is also cheaper than seafoam like 5$ for the liquid one and 8$ for the spray can

We have been using plain ordinary kerosene for years. We pour it into the oil and run it for 20 mins before we change it...........to using it the same way the Gm crap works, let it suck off from the vaccum line. Way cheaper and way more many uses.
Kerosene.....who knew.