A little story of water cleaning gone bad.
In the summer months I would get a ping or a knock with the A/C on. I figured it was a carbon build up problem. The vehicle is a 1999 Dodge Grand Caravan with 340,000 miles on it. Yes, you read that right, 340K Miles. Original engine and tranny, niether of which has been opened up. As the original owner, I know this to be true.
Oh, ARX on both engine and tranny since 200K. A full clean/rinse cycle every 75K and maintenence doses in between.
Anyway, in an effort to get rid of the carbon in the cumbustion chamber I have tried all of the usual cleaners like Regane, B-12, Seafoam and many more using all of the different ways to remove carbon written about here at BOTIG like soaks and flooding the intake and putting it in the gas. Nothing seemed to cure the pinging.
This spring I decided to do the water method. I was considering getting a water injection unit, but then, right before I was going to change my oil, I decided to fill the 2 gallon pump up lawn and garden sprayer with 1 gallon of hot water and spray it right into the intake via the throttle body when the van was hot and see if it would get rid of my carbon problem.
I removed the rubber boot that connects the throttle body to the air filter, started it up and revved it up a bit as I sprayed water into the throttle body. It ran rough to say the least, but I kept at it until the whole gallon of water was gone.
I then changed the oil and took it for a drive. The ping was now almost gone. I was pleased. Finally, after years of trying everything, the water seemed to do the trick. I decided that from now on I would use the water technique before each oil change to keep the carbon from building up again.
A few thousand miles went by and the weather was getting hot and the A/C was on all the time. The ping was still almost gone, but I wanted it completely gone, and I wanted to run 87 octane as prices were nearing 4 bucks a gallon by this time (July). I was itching to try the water trick again and change the oil.
But this time I was going to go even further, I would use two gallons of water and really clean the carbon out!
Sounds good so far right?
Went out and bought new oil and a filter and set about on my de-carboning mission. I sprayed and spayed and I held the throttle open to keep it from stalling. After I'd sprayed in about a gallon and a half I noticed a whole lot of steam coming out of not only the tailpipe, but the breather hose on the valve cover. Hmmm....Somehow I correctly surmised that this was NOT GOOD and quickly shut off the engine.
When I pulled the dipstick, what was once oil now looked like chocolate milk!!
Oh No!!
I drained the oil and pulled the filter. I then refilled it with some used oil and a used filter that I had and started it up.
It still runs! Whew.
I pondered the error of my ways and decided there wasn't much I could do about it now except to drive it a bit and hope I can burn off any water that might still be in the engine.
I drove it with the used oil for a couple of days and then changed it out for fresh oil and filter. That was ablout 10,500 miles ago. (Yea, I drive a lot.)
As for the ping, it is still there, but very very slight with 87 octane gas. No ping with 89 and 91 octane. Not bad. Lucky for me I didn't destroy the engine.
Moral of the story, BE CAREFUL!
Go easy on the water as I think it does have it's uses in removing carbon build up, but you have to make sure you don't drown the engine in it.
Biron
