Tell ya what, I'll be a nice guy (taken from one of my previous posts):
I'm just going to say this. If you have no idea what you're doing, don't do it. You can seriously damage your vehicle if you don't go about doing this correctly.
If you were looking for a complete write up for Seafoaming your car, here it is.
2 cans Seafoam motor treatment (liquid)
1 can Seafoam Deep Creep (spray)
Pliers (pretty much any type will work)
3/8" ratchet extension
Spark plug socket
This write up is intended for those of you wanting to "Seafoam" (as it's commonly referred to) your motor. This process is used to remove carbon deposits from your throttle body, IACV, intake manifold, intake ports, piston tops, and exhaust ports - basically the entire intake and exhaust system for your vehicle. It will also clean out deposits from your gas tank and fuel lines, as well as cleaning your fuel injectors. As long as you follow the directions closely, you won't have any problems during this process.
Please note - I do not recommend this on very high mileage motors (200k+). Depending on how well your vehicle was taken care of, it's possible that the sludge and carbon inside your motor is all that's holding it together yet. The two vehicles I ran this process on both had around 120k. I didn't run into any problems with this many miles, but I've heard of people with very high mileage motors doing this and having problems with burning oil afterwards. Basically as long as your motor isn't beat to **** and in terrible shape you should be fine.
I started first of all with a full tank of gas and poured one full can of Seafoam motor treatment into the gas tank. I ran through this tank of gas before starting the process listed below.
1. Warm your vehicle up to operating temperature, then shut off vehicle.
2. Remove air cleaner tube to gain access to throttle body plate.
3. Start vehicle and allow to idle.
4. Begin slowly spraying Seafoam Deep Creep onto throttle plate, spraying small amounts every 5-10 seconds. Do not allow vehicle to bog down or die out.
5. Be sure to spray into the IACV which will be small hole just before the throttle plate.
6. Make sure to spray larger bursts onto the throttle plate while revving up the motor using throttle wheel.
7. After using around 1/2 the can, shut car off and soak the throttle plate, IACV, and intake manifold with the Seafoam spray and let sit for 15 minutes.
8. Restart vehicle (will probably be a little harder to start than normal) and allow the Seafoam to completely burn off. Shut car off.
9. Reconnect intake tube, then locate brake booster vacuum line (will be a long black vacuum hose running from intake manifold to brake booster located on the firewall).
10. Use your pliers to remove the hose clamp and pull the vacuum line off the brake booster. Start vehicle. You'll notice the vehicle idling higher and/or have a surging idle.
11. Begin slowly pouring the Seafoam motor treatment into the open vacuum line, pouring in approximately 2 tablespoons at a time. Do not allow motor to bog down or die out.
12. Be sure to rev vehicle up and down while adding the liquid. Do not add too much at a time or you'll run the risk of hydrolocking your motor. This won't be a problem if you stick with the small amounts (2 tablespoons) at a time.
13. After running approximately 2/3 of the can through the system, reconnect brake booster vacuum line and allow vehicle to burn off all of the liquid.
14. Turn off vehicle and let sit for approximately 15 minutes, making sure that it has cooled down throughly (warm to the touch, NOT hot).
15. Remove all 4 spark plugs, then pour approximately 2 tablespoons of Seafoam motor treatment into each cylinder.
16. Pour the remaining 1/3 can of Seafoam liquid into your oil system using the oil fill cap.
17. Let sit for 15 minutes, allowing the Seafoam to soak on top of the pistons.
18. Replace spark plugs and start engine (will be harder to start than normal).
19. Go for a sprited drive, making sure to rev vehicle up and down. Do not drive for more than 5 minutes or lay on the rev limiter during this time.
20. Change oil, spark plugs, and fuel filter.
21. If your vehicle threw a CEL, it's more than likely a code for the IACV or a misfire. To reset it, simply disconnect the negative battery terminal for a few minutes then reconnect it and it should be gone.
Make sure that you change these 3 items after this process. I've seen a lot of people that didn't change their oil and ran the car with for many miles with the Seafoam in it and damaged their motor. This is because the Seafoam cuts through the oil and lowers the viscosity. Like I stated in my steps, I only ran it through the vehicle for less than 5 minutes, allowing just enough time for it to circulate through the system to clean things out and then changed the oil afterwards to remove it from the system. Also as I stated above - do not add too much of the liquid into the brake booster at a time or you run the risk of hydrolocking the motor. I've done this two times now on two seperate vehicles and haven't had a problem. This process works well as long as you do it in moderation.
It's amazing the difference it will make once you burn all the Seafoam off and change the oil, plugs, and fuel filter. It'll make your vehicle idle smoother, run smoother, and gain a slight bit of power all through the RPM range. Obviously you shouldn't be expecting a 20 HP increase, because all this will do is gain you back the HP you've lost due to carbon build up and aging parts.
I hope this clears everything up for anyone wanting to do this. If you have any more questions, feel free to post them.