Just did water decarbonization on Mazda 3

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WOW!!!!!

My 2007 Mazda 3i has 42,000 miles on it. I have owned the car 3 years next month. The car has seen a steady diet of FP60, Regane, Lucas UCL, and MMO (obviously not all at once). I decided to do a water decarb to see if there was any difference in the car.

Took her out for a short 15 minute spin first to heat the engine. Hooked up 8 feet of 3/8 inch fuel line to the brake booster nipple. Sat in the drivers seat with a gallon jug of distilled water and ran the open end of the hose to my location.

Started the engine and dipped the tip of the hose into the water. Kept the RPMs at 3000. Got into a rhythm....dip the hose for a split second...raise it for half a second or so.....dip it back up.....raise it instantly back up.

I went through about half a gallon of water in 3 or 4 minutes. I could see smoke out the pipe when I first started but near the tail end of the run I couldn't see anything.

Turned the car off and disconnected the negative post for a few minutes to reset the ECU. Reattached the brake booster line. Went for a drive to dry her off and WOW!!!!

Man she is unbelievably responsive now, just like the day I drove her off the lot. I always wondered where in the heck my power went as the years went by. At idle, you cannot hear or feel that the car is on. It's just crazy.

After a 20 minute highway drive I pulled back home. Looked at the oil filler cap and saw just a small amount of milkiness on the inside of the cap. I figure it's just some condensation. The oil on the dipstick is still good looking. I'm going to change the oil out tomorrow morning just to be safe.

I highly recommend this IF YOU GO SLOW. You COULD possibly hydrolock your engine if you suck in too much water too quickly.
 
I would love to do this with my 3 but I'm to afraid of Hydro lock ... any other safe ways to do it ...
 
Nice work...and you didn't have to pay $10 for a 16oz bottle! I figure that if I did this with my ford I would use San Pellegrino for it's exquisite mineral content.
 
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Originally Posted By: Ndx
I would love to do this with my 3 but I'm to afraid of Hydro lock ... any other safe ways to do it ...


Keep the RPMs at 3000 to atomize the water. Just barely dip the hose in the water for a split second and then take it out for a second. Repeat.

I wish I could see the internals. What blows my mind is how much a difference there is even after using a steady diet of fuel adds.
 
Originally Posted By: pickled
Nice work...and you didn't have to pay $10 for a 16oz bottle! I figure that if I did this with my ford I would use San Pellegrino for it's exquisite mineral content.


Yep....69 cents for a gallon and from what I understand water works better than Seafoam, GM Top End, B12, etc.
 
"any other safe ways to do it"

Get a metal needle one would use to fill a football or basketball. Put the end of the hose around that, and dip that in the water. It will slow the rate of flow obviously.

I'm not sure how far up the line the brake booster is, but obviously you want to be as far upstream on the intake as possible but after the MAF (if you have one, I don't know).

I might prefer seafoam, but it's hard to beat free.
 
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Originally Posted By: Ndx
I would love to do this with my 3 but I'm to afraid of Hydro lock ... any other safe ways to do it ...


Unhook/open your air intake tube. Use a spray bottle (ie, Windex bottle) filled with water. Spray water into the intake tube, while revving the engine manually with the throttle cable. That's what I do on my 2002 Cavalier, and it works well. I'll be doing this on my car vey soon, as I'm due for my emission test very soon.

Agree with the OP; you DO feel a difference in the way the car runs after doing this.....
 
No throttle cable. It's fly-by-wire.

The brake booster nipple is right after the TB and right before the manifold. Has a red lockdown ring on it. Can't miss it.
 
Originally Posted By: Greggy_D
Turned the car off and disconnected the negative post for a few minutes to reset the ECU. Reattached the brake booster line. Went for a drive to dry her off and WOW!!!!

Man she is unbelievably responsive now, just like the day I drove her off the lot. I always wondered where in the heck my power went as the years went by.

Please keep us posted in a few hundred miles when the ECU has had a chance to adjust. I'd be interested to know if just resetting the ECU had any effect.
 
I tried to spray water through cab using Windex bottle on my lawn mower; I could not find a vacuum hose. Unfortunately, it was a complete failure as the lawn mower promptly died and took lots of pulls before it fired up again. I was very careful in spraying the water. It was room temperature water though.

Generally, the engine is very difficult to stall when I spray carb cleaner or Seafoam Deep Creep through the carb. I really have to lean on that spray button before it will complete sputter and die. I was quite scared when the single puff of water killed the engine and was so hard to restart.

- Vikas
 
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Originally Posted By: d00df00d

Please keep us posted in a few hundred miles when the ECU has had a chance to adjust. I'd be interested to know if just resetting the ECU had any effect.


I tried resetting the ECU back in the Spring. No change. This procedure today did wonders.
 
The brake booster line is pretty large for this procedure.

I always used the smaller vacuum lines for the emissions system (something really small, like 1/8" ID) to keep the flow low.
 
Just making the vacuum draw it from the passenger compartment should limit the amount you can pull.

I've done this in the past while doing highway speeds. If you're using anything that's mildly combustible, you'll leave a plume. Central vac tap is critical.
 
Originally Posted By: KLowD9x
The brake booster line is pretty large for this procedure.

I always used the smaller vacuum lines for the emissions system (something really small, like 1/8" ID) to keep the flow low.


My dad rigged up a needle used for filling up footballs to a hose and uses that to draw water throught the brake booster. It seems to work well for us. My dad said locking up an engine would be very hard since the water is being drawn through a small opening. It just takes a little longer but it works.
 
I did something similar with my car, but I did it during the winter. This job bit me when some of the residual water in the vacuum lines froze and screwed up my MAP function for an evening.
 
I don't recall ever doing it in the winter time. We'd have any of that kind of work done before the real cold set in. Definately something worth remembering, thanks!

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