stevesrl

On 11/15/09 I did the Seafoam cleaning treatment to my 2005 RL (96K miles, as far as I know it has never been done before). The treatment is to clean crud/carbon buildup in the gas system and engine compartment. I was a little apprehensive to do this Seafoam treatment. I’ve read up on this subject (3rd Gen TL Forum) and was afraid that since it probably had never been done on my car before; I may have too much carbon buildup that would be released at one time and would foul plugs, get gunk on oxygen sensor, etc., etc., and result in multiple codes being thrown and make my dash light up like a Christmas tree. I decided to do it based on others doing it with just as high mileage or higher than me without any problems.

3 Different Seafoam Treatments Are Provided Herein

1) Gas treatment.
2) Intake Treatment
3) Oil Treatment

GAS/INTAKE (1, 2)

These are both done at the same time.

2 oz/1gallon gas. I added a full 16 oz can of Seafoam to a ¼ full gas tank and then immediately filled up to a little less than ½ a tank. This gives me approximately a 2oz/gal concentration and a volume of approximately 8 gallons. It also allows the Seafoam to mix well in the tank.

Drive around for approximately 10 minutes as to get the engine/exhaust hot.
Seafoam will be added to the intake manifold by using the vacuum port directly after the throttle body.

You have to remove the intake manifold plastic cover to gain access to the needed vacuum port. The cover is held on by 4 fasteners. The front two fasteners require a plain screwdriver to remove. The back two fasteners are pressure fits. After twisting the two front fasteners, CC ¼ turn, simply pull up on the plastic cover and it will come off.

On top of the right side of the intake manifold and immediately after the throttle body you will see a port with a flex hose attached to it (This is the vacuum port you need). Use pliers and squeeze the retainer rings and push them off the flex tube. There are two retainer rings that I pushed away from the vacuum port. Then use a plain screwdriver and push off the flex hose from the port.

Connect a 12” length of clear flex hose to the port. I used some very small flex hose that was actually small enough to slide in the port. Did not slide over it as the flex hose I removed was attached. After I slid my very small flex hose into the port, I used electrical tape and wrapped a few rounds ½ on flex hose and ½ on metal vacuum pipe. I did this to make a good seal. If you place your finger over the hole on the other end of the flex hose you can feel the suction (car has to be running). You can also use ¼” size flex and connect to the outside of the vacuum pipe. Simply use same size flex as pipe already connected to it. I recommend using clear flex so you can see what is going on (How much you are adding) when you add the Seafoam to the intake manifold.

Pour 8 ounces of Seafoam into a cup and hold the cup at a 45 degree angle. I had my wife sit in the car and hold 1,100-1,300 rpm while I gradually let the Seafoam get sucked in the manifold by letting the flex end just touch the top of the fluid level in the cup being held at a 45 degree angle (This simply allows air to get mixed in with the Seafoam and limits the amount you are adding at one time). I did not submerge the hose in the solution. So I would let a little bit get sucked in, pull flex away from liquid level, wait 5 seconds, and repeat until all the 8 oz of Seafoam were sucked in. The car will run a little rough each time the Seafoam is sucked in, so that is where the wife comes in. She just mashed the gas a little as not to let the car shut down. We did not have any trouble at all. For kicks, I did submerge the hose one time and a good bit got sucked in at one time. When I did this, the car nearly shut off. Only did it once and the rest was gradual. The whole process took about 12-15 minutes to suck down 8 oz of Seafoam. Don’t do this in an enclosed garage…do it outside so the smoke can dissipate. Smoke is generated out the exhaust during the cleaning procedure (This is normal).

After 8oz were sucked in shut the car off and allow to sit for 15 minutes. This gives the Seafoan a chance to dissolve contaminants.

Restart engine. Note it has been reported that after restarting the car it will run rough, smoke, and CEL may come on. When I started the car it ran fine, smoked a little, and no lights. After 2 minutes and car was running stable, I headed for the road for the after drive step. Smoking is normal.

Drive 10 minutes at 4,000 rpm. Note this is about 65mph in third gear. If your cars smoking like mad you will want to be on a back road (Plan ahead).

After the 10 minute at 4,000 rpm drive, do 10 accelerations from 10 to 65 taking the rpm’s to 5,500 max before gear change. That is, accelerate in sport mode but don’t exceed 5,500 rpm.

What this is doing is blowing all the gunk out of the system.

Intake treatment is now completed and to finsh the gas treatment, simply run out the remaining fuel that has the concentration of 2 oz/gallon. Do not refuel until tank is empty.
Notes/Comments (1, 2)


Plenty of information on Seafoam on 3rd Gen. forum or go to Seafoam’s website. My write up is just a depiction of my experience so fellow RL owners could hear from one who actually Seafoamed an RL with high mileage.

Yes, I was scared to do the Seafoam treatment! I thought I might be asking for trouble with sensors and plugs. Specifically, I risk getting too much gunk on them and my vehicle throwing codes, and the check engine light coming on because my car has almost 100K on it. I introduced the Seafoam slowly into the preheated intake manifold and had no issues what so ever.

First timers repeat in 1,500 miles then treat every 15,000 miles. Also recommend gas treatment only every 5,000 miles. Seafoam cost approx. $10.00/can (16 oz) and is available at car stores (Advance, Napa, Autozone, etc.).

THE RESULTS:

Maybe it’s just me but my car does seem to have the slightest increase in throttle response after doing the Seafoam treatment.

Absolutely without a doubt my car runs quieter and idles more smoothly!

After, I run out the remaining 3/8 tank with the Seafoam, which completes the gas treatment, I will fill her up and check mileage with a full tank of premium gas (I always run the good stuff: 93 Octane BP/Amoco/Exxon). It has been reported that this cleaning can increase mpg. I will know by the end of the week and will advise what I experience.

Just because of smoother idling and quieter engine, I would recommend this. I have hopes that gas mileage will also increase. We will soon know.

3) ENGINE OIL TREATMENT (I will do next weekend)

For cars with 50K or less:

Simply pour in 8 ounces into the engine oil, drive 50 miles and change oil and filter.

For cars with 50K or greater and never been Seafoamed before:

Change the oil and filter.
Add 8 ounces of Seafoam to the oil.
Dive 50 miles
Change the oil and filter again.

Note: I will use cheap oil and filter for the first change and the second change I use my normal parts oil change parts (OEM filter and synthetic oil).

Note: I am simply changing the filter before the treatment as to make sure the filter has the capacity to hold all the contaminants being released. My car has high mileage so it could be bad and want to start off with a new filter to catch all the contamination.

After this initial Seafoam oil treatment I will repeat every 15,000 miles but will simply add 8 oz of Seafoam 50 miles prior to regular oil and filter change (Same process as listed for cars with less than 50K).

neuronbob

Thanks for posting this. I'll have to place this in the Garage in case someone else wants to Seafoam. I have no idea how much good the stuff actually does, but some people certainly swear by it.

woodek

I love Seafoam.
I Seafoamed my 98 CL (intake) and MAN! What a difference it was. It smoked like a dog for a little while, and that was the only down side. It DEFINATLY made a BIG difference. It had 85,000 miles on it at the time.

I want to do this with my RL but was a little worried about what vac hose to use. I assume the hose is obvious when the intake manifold cover is removed?

I JUST changed my oil (last Fri), so I'll have to wait until I get closer to my next change before doing this.

Thanks a bunch!

stevesrl

When you take the cover off, it is obvious what pipe you connect the flex hose line to. There is only one vacuum port on top of the intake manifold. It is on the right side (If your standing outside the car facing the windshield). This port is immediately after the the throttle body and mounted on top of the intake manifold.

Chas2

Ain't that the truth. I seafoamed my old Legend, and there was so much smoke my neighbor came running over thinking the house was on fire...I guess I need to find another place to do it besides the driveway. Like a windy parking lot on a weekend...

TampaRLX-SH

In my former Isuzu, I used Seafoam as a gas additive on a regular basis. I never did the full blown carbon blow out. I also added some to the crankcase before an oil change. The Isuzu's valves and injectors would get a bit clicky and one pet peeve of mine is any engine with a valve tap.

I sold that Isuzu to an associate whose son is an automotive restorer. He has broken the engine down and rebuilt it recently (with 257,000 original miles). He was amazed how clean the engine was internally and even called me to ask what type of regular maintenance I did on the Isuzu. I told him I used a half can of Seafoam in a full tank about once a quarter, somewhat like using Techron or some other high quality fuel system additive. Other than that, just regular maintenance per the manual.

I still am hesitant to use it the same way in the Acura. I keep reading where Honda does not recommend additives, and since I maintain my vehicles religiously from new, I don't have a need to 'restore' engine performance or recondition. Other than the Techron ever six months, I am by the book with my Acuras.

hugous

I want to do this soon, let see what will happen. I hope my car still survive.