Hey guys/gals. Just back to reading some threads. I had the intake manifold valve cleaned last November from the carbon buildup. My check engine light has come on a few times since then and I took it to Advance Auto for the code, but was able to make the light go out after some hard driving. Unfortunately, it's back on again and the cold temps in Ohio is making it hard to get the engine hot enough to burn it off. Since I was quoted a cost of over $2000 to get it cleaned, I'm trying to avoid that. Seems to me that there should be a recall to fix this. Anyway, I've read some of the threads giving instructions to clean it (thanks Jon for the video) but not sure my husband will be willing to do this. I've seen some threads mentioning Seafoam, but not sure what that is. My car's a 2004 manual with over 80,000 miles. I'm not experiencing any performance issues (and hope I won't) but want to find a way to avoid the buildup.

As a side note, I'm wondering if the automatic transmissions are having this problem. How would they keep the RPM's high enough to burn it off?

Can anyone tell me what the Seafoam is and how to use it? I love driving this car and would like to keep it for another five years. Any other tips would be appreciated.

 

Seafoam is a decarbing liquid/spray. It was historically more used for nautical outboard motors (hence the name) but has become the preferred decarbing spray for automotives as well. Mazda has their own spray which is similar in formulation. You can follow the Mazda decarbing procedure for significant carbonation, or use in the gas tank as a preventive measure.

In an automatic you can use the paddle shifters to hold the transmission in a lower gear to facilitate higher rev's, noting that it still won't rev as high as a manual trans, but high enough.

I'm sure in your reading here you've seen "a redline a day keeps the carbon away" and it really does help. Periodic additions of a fuel system cleaner to the gas tank, like Lucas or STP or aforementioned Seafoam, are also helpful as is use of a quality gasoline that has added detergents, e.g. Mobil and Shell. Winter gasolines in our colder climes tend to be 'richer' as well.

Additionally ensure that your ignition system is operating properly. A lot of carbon comes from lack of proper spark (caused by worn sparkplugs, coils, 'plug cables and even low output battery/alternator).

You may also want to get an engine compression check done now to baseline your vehicle and to use to compare against in the future.

 

Seafoam will not clean out your intake - that seems to be what you are concerned about .

Best way to stop that gunking up is to fit a catch can .

 

Thanks for the info! I'll pass it on to hubby and see what he can do. This is only thing I've had problems with in the five years I've owned the car and probably wouldn't be dealing with this now if I had been told to keep the RPMs up. I was using the higher gears to save on gas and do a lot of highway driving.

 

You don't have to spend long periods of time at high rpm. It's the opening and closing of the valve that keeps the stickies away.