Just though I would quickly review a product I have been hearing about for a while but never tried until today. Subaru Upper Engine Cleaner is sold through your local Subaru parts dealer, and costs about $16 a can.
This products is used by Subaru to clean carbon buildup, and other crap from your intake manifold, and head. After reading a few good reviews I tried it out on the MX5.
Here is the can.
These are the instructions on the can, bring the car up to running temp, then turn it off. Spray half of the can into one of the lines going to the manifold.
Let it sit for about 5-10min, and start it up. This is what should happen..
It'll run like crap so keep the revs high, so it doesn't stall.
When the car is running alright and most of the smoke has cleared, unplug that same vacuum line again and empty the other half of the can into the manifold with the car running. Make sure to keep the revs high or it will die doing this.
Once the can is empty turn off the car, and let sit for another 10min. Then start it up for more smokey action. Then once its running clear go for a 15min drive.
After my exhaust had finished smoking up the street I went for a spin, and immediately I could feel a difference in the engines response. Its feels soo much better than before, it idles smoother, revs alot faster, and goes harder (butt dyno). I though this stuff wasn't going to do anything other than empty my wallet, but I was proven very wrong.
I highly suggest getting a can from Subaru and trying this stuff out, for $16 you cant go wrong. Im making it a permanent part of my servicing regime.
