I'll get to the title in a minute. After reading up on CGP about doing a GM Top Engine Clean I decided to go ahead and do it today. It requires an oil change afterwards and I'm due for one so why not do this as well.

Thanks to Jason Penneman for this information

First of all the goods you will need:

GM part number 1050002 – GM top engine clean
Full set of new spark plugs if current plugs are old
Oil and oil filter
2 feet of 9/32 inside diameter hose (Auto Zone or other parts store will carry this)
**The last step in this process involves an oil change, so you may want to wait until it is time to change your oil before doing this**

The actual operation:

1. Pull the middle vacuum line off the top of the blower by the throttle body.(There should be 3). Run a line from there into ¾ of the can and mark the hose your using to keep it ¾ submerged.
2. Start the car (Your car will need to be at operating temp before proceeding) and put the line into the bottle of top engine clean. Have someone hold the RPMs up because the car will want to stall. The car will smoke a lot during this part of the process. This is normal
3. After 3/4 of the bottle has gone in let off the gas and let the car choke on it and die. If it doesn’t feel like it is going to die, turn the car off anyway.
4. Let it sit for 20-30 minutes (soaks during this time) then start the car and let it suck the rest of the contents of the can.
5. Reattach the stock vacuum line.
6. After that, drive (Aggressively) to get the rest of the stuff out for a few minutes. Do this at night or away from everyone. It will smoke quite a bit.
7. Perform a fresh oil and filter change.

Now for the pics:

Here are the goods! You only need 1 can but I bought 2 just in case (was hard to find a dealer who stocked it). The carb cleaner I used to check for vacuum leaks.



The middle vaccum port is the I used. If you are NA then a suitable small vacuum line should work


The setup installed and ready to go:


2 things, this produced a TON of smoke, I think I had neighboors ready to call the fire department. You might need 2 people to do this as the car really wants to die upon initial start. Someone needs to hold the throttle open a bit to keep it running so it sucks the stuff in. I'm currently in the "let it soak" phase and will finish it up soon. A lot of people call this knock reducer in a can because it removes all the carbon buildup on the valves and in the cylinders reducing pressure buildup and hence KR. i'll get taps on the car once its done to see if it helped at all. The cleaner was about 6.50 a can, tube cost 1.50. If your high mileage expect some improvement for sure. I would say this should be part of a tune-up. Remember to change your oil aftewards as all the engine crap gets deposited into the oil.[/b]

Thanks, Todd! Let us know how it goes! My only concern would be on a higher mileage car. You'd think too much carbon would clog the cat or muffler? Any thoughts?

I had not thought of that but most of this gets vaporized in the cylinder. If you have an old cat than i would assume this could clog it depending on the amount of clog already present.

Finished letting it soak, sucked the last 1/4 can in and took it on an agressive run. 30 seconds later a cop had me pulled over. He wanted to know why I was driving a car with an obvious engine problem (smoke was ALL over the place). I explained to him what was going on and that it shouldnt smoke for more then a minute or two. I guess he was a car guy because he let me go but told me to open it up "on a back street".

I recommend either doing this at night, or in open country. I can't tell you how much smoke this put out. I have not got a chance to get a tap on it yet. I just finished changing the oil and have some work to do so it will have to wait. Here are some more pics from under the car (fram sure drain kit).

Car ready for minor surgery...


Oil after top engine clean (this oil only had about 3K Miles on it)


Fram SureDrain Kit



SLP Hi-Flo Cat

kinda of like "SEA-FOAM"?

Yeah seems like seafoam. My friend used seafoam on his lincoln LSC and he said it did wonders.

General consensus is that this is safe for all cats.

:runsofftothedealer:


I can't imagine what mine would look like with 10 years (100k) of buildup!

Yes its simillar to Sea Foam.

You can work the the throttle cable with your free hand while you hold the tube in the can of engine clean.

Also watch the spark plugs, they can get fouled up by the gunk. Sometimes its better to wait untill you are doing the plugs and go for a complete job?

Yea, I just put my plugs in about 2 weeks ago so I wasn't to worried about it, but plugs are listed in the parts to get just in case (so your not stranded if you do foul your plugs)

how does it run now? any noticable change?