[mgh]

Originally Posted by dhanushs

Yeah, I was going to ask that question. "How does it decarb the engine?" .

However the ironic thing is, today when checked my car's mileage, (tank to tank) it gave me about 15.57kmpl, in 50%city conditions(1-2-3 gears), 50%highway for a distance of 110kms.(I usually get 14 in those roads/conditions) That is pretty coooolllll!!!..

Reminds me of something that happened long ago. I read in a technical magazine that adding a very small amount of water to petrol improved fuel efficiency. They said that water should be only added to the extent it can dissolve in petrol. What they added was that as the boiling point of water was lower, it would flash into steam before the petrol evaporated, and thereby cause bigger droplets to break up into smaller droplets, improving the atomisation of the fuel.

I mentioned it to a colleague of mine working in the chemical laboratory, who had a moped. One Saturday, he put 1 litre petrol in his moped, and brought it to the factory. He used a closed separating funnel to dissolve distilled water in the petrol, and then drained out the free water along with a couple of drops of petrol, to ensure no free water in the petrol. He put it back in his moped and went off to his in-law's place 20 kms away. He came back beaming on Monday, saying that normally he would barely have enough petrol for a kilometer after coming back. This time after coming back, he drove another ten kilometers, without the petrol running out. He also said that he checked his spark plug after coming back, and it was clean and shining like new. The roads in that area do not have traffic, so traffic conditions could not be responsible. I left the place soon after, so do not know whether he tried it again.

Now the solubility of water in octane is less than 1 ppm, but it has good solubility in the antiknock chemicals added to petrol these days. So, much more than 1 ppm can be dissolved in petrol! Also as water ppm increases, the solubility of the antiknock chemicals in petrol reduces, and if you add too much water, the antiknock chemicals along with water will separate out from the petrol. So there is a limit to the amount of water that can be added without causing problems. Since no data are available, telling how much is too much, it is dangerous to try and add water to petrol.

A bottle of soda in a 50 litre tank of petrol would not be more than one percent, and from what I had seen happening in the separating funnel that day, mere sloshing would not send up water droplets into the petrol, which could be why you did not face a problem

Would be interesting to know how much water they found when they cleaned your tank.

[echo77]

I wonder how many petrol pump owners are beaming at your post, mgh

[wildsdi5530]

And how many service stations are crying over it.
Free service done. No expensive engine decarb foams. Just 5 mins and your vehicle is new again.
Cost of service: Rs.10/-

[sgiitk]

In the early 80's water injection was the rage in the US. Then they found it reduced engine life dramatically.

[vijaycool]

I think the effect is similar to engine decarb. The water will not enter inside the chamber in the liquid state rather in vapor. After driving some kilometers the carbon is removed hence the knocking is reduced. This causes the ecu to sense and lean the petrol mixture which in turn increases the mileage. I may be wrong. CO2 in the soda will leave when its exposed to the bigger tank volume.

[mgh]

Originally Posted by sgiitk

In the early 80's water injection was the rage in the US. Then they found it reduced engine life dramatically.

A wikipedia article on water injection-purpose was cooling of engine
Water injection (engines) - Wikipedia, the free encyclopedia
This uses much less water. The purpose is to improve atomisation.
Even to try it, you must ensure that you add enough and not too much. It is very difficult without a separating funnel. I would not at all recommend trying it on a car, as the quantity of petrol involved is too large to handle in a separating funnel.

[KA18]

My 2CCs to the above posts:

If the water or any other liquid apart form petrol enters the tank, it may result in choking of fuel lines, blocked carburetors (if it is present), misfires, starting problems, loss of power, engine seizure and even damage of Catalytic converter.

However in practical situations, water does get into the tank (even if in a tiny proportion) somehow whether we like it or not.
Usually, the water drops are burned away in the cylinder's high temperature resulting in an occasional "bang" (misfire) from the engine thereby appearing to 'decarbonise' the engine. But as water also reduces the lubrication in the engine, causing wear and tear of the moving parts and shortening the engine life.

Obviously, as the temperature reduces, the problem will be more pronounced because the water starts flowing more in liquid form.

Anyway, a clean up of the fuel system is recommended for longer engine life.

Originally Posted by dhanushs

However the ironic thing is, today when checked my car's mileage, (tank to tank) it gave me about 15.57kmpl, in 50%city conditions(1-2-3 gears), 50%highway for a distance of 110kms.(I usually get 14 in those roads/conditions) That is pretty coooolllll!!!..

Originally Posted by dhanushs

Update:
Today the strangest thing happened to me and it is that my car traversed 238kms on 13.72 liters of petrol, 80% A/C on and in that about 40kms in Calicut city traffic(1&2 gears). 17.3kmpl fuel efficiency. Now is that explainable?

I think the basis on which you have calculated the mileage is giving you this error.

First, you had tanked up your car, which would be
Full tank = Fuel Consumed + Fuel Filled

and drove for some kilometers and then kids put Soda into your tank.
So, it will be the fuel in tank + Soda

When you do another tankful, it will be
full tank = fuel consumed +Fuel filled + Soda

So, you will have filled less fuel than it is actually supposed to be filled because Soda is occupying its place in the tank.

I hope you understood my point.

To find out if your car is actually giving more mileage, do another tankful to tankful test and then calculate to find out if there is an increase.I may be wrong in any of the points mentioned in this post and I would welcome Expert's opinion in the matter.

[dhanushs]

Originally Posted by KA18

I think the basis on which you have calculated the mileage is giving you this error.

First, you had tanked up your car, which would be
Full tank = Fuel Consumed + Fuel Filled

and drove for some kilometers and then kids put Soda into your tank.
So, it will be the fuel in tank + Soda

When you do another tankful, it will be
full tank = fuel consumed +Fuel filled + Soda

So, you will have filled less fuel than it is actually supposed to be filled because Soda is occupying its place in the tank.

I hope you understood my point.

To find out if your car is actually giving more mileage, do another tankful to tankful test and then calculate to find out if there is an increase.I may be wrong in any of the points mentioned in this post and I would welcome Expert's opinion in the matter.

Dude, all my calculations are done assuming there is not enough SODA left on my tank as my car has traversed atleast 1200kms(one week) after the incident and calculations. and on the first place the amount of SODA gone into the tank is just below half a liter. So I dont think half a liter in a tank of 50 liters and that too after 1200kms would make any huge difference in calculation.

P.S- No offense, I'm just making the situation clear.

[sfilinto]

I believe the Fuel Filter is toast. Hence the engine does not get enough fuel in high altitude. there was a post somewhere on this forum where a scorpio owner had a similar problem on a drive to leh. ( with adultrated fuel ).

If i were you i would flush the tank & fuel lines.

[dhanushs]

UPDATE:

I just got back my car after the fuel tank/lines flush, I had given it to my local maruthi guys. The reason I decided to give it to them, is that 1. I did not have time AT ALL, 2. Those guys seemed that they knew the mechanicals very well(they claimed to have done this several times, when petrol bunk boys accidentaly mix up fuel) . 3. I guess this is a 'low error' task, so I could afford to compromise the quality of work, if there was any.

Observation: Zero% of water or SODA in the tank, and fuel lines. I guess they got burned up. Engine and related parts are running perfectly fine. After the two time mileage calculation (15.57 & 17.3) I'm yet to check it the third time. I guess the car's doing pretty good - will let you guys know for sure. At last now I can breathe fresh air .

Lessons Learnt:

1. Never let kid's near your car when your away. If thats not possible, atleast LOCK the car. (This incident could have been catastrophic, if I dint know about this). Also I thank god that they only put in SODA, not some 'other' things.

2. Less than 500ml of SODA will not cause any harm to your engine when mixed with 50L(even more as I observed problems after about 500 kms) of petrol. Actually it has proved good in this case - mileage increase (not sure about the tech details)

3. If you get into any sort of trouble, get to the solution(atleast know the technical details from experts) immediately before cranking/using the car, or else you could end up spending much..much..much.. more than the actual repairs. Not that I came across any major problem's, but could have.

Finally, If you love your car as much as you do your wife, the car god's will definitely be on your side.

[sgiitk]

Originally Posted by dhanushs

UPDATE:

Observation: Zero% of water or SODA in the tank, and fuel lines. I guess they got burned up. Engine and related parts are running perfectly fine. After the two time mileage calculation (15.57 & 17.3) I'm yet to check it the third time. I guess the car's doing pretty good - will let you guys know

What did you expect. Water just got mixed up into the diesel. You would have seen the same after 100km!