power for injectors
 

I'm thinking about idea to create four switches for injectors. One for each.
So I can switch off as many as i need when I'm driving.
I have straight-4 1.8 66kw engine and I think that if I drive with constant speed, then I need only three cyl or even 2 to keep speed.
But question is: Is it somehow dangerous for my engine or for other components?

Hi atsik,
its a good concept but im not sure you will get the affect your after. The amount of fuel used will reduce but also the power output will reduce in line. stopping the fuel going into a cylinder from a 4 cylinder engine wont make it as efficient as a 3 cylinder engine unfortunately. This is because the losses come from moving the piston up and down the shaft and all the friction involved.

I have read from other threads that cutting fuel to one injector is likely to cause the other injectors to compensate because the O2 sensor will see more air coming in compared to petrol and the ECU will compensate accordingly.

If you are after less fuel coming in you can adjust your idle control which will reduce the fuel used when your foot is off the pedal (will also make your car slow down accordingly) Alternatively you can cut off all the injectors which will effectively give you engine breaking I think (someone feel free to correct me here).

The best solution I have come across for what i think your after is pulse and glide as the pulse uses all the available engine power then when you glide the engine isn't using much when idling or turned off.

Regarding your actual question, i personally dont think it will cause damage to the engine other than maybe unbalancing as you wont have the force of one piston. maybe less lubrication on that piston shaft due to the lack of petrol. Maybe someone else can give a better idea here if you still want to pursue the idea.

Good luck

well... as soon as i can afford a mpguino or something similar I'll find out what's mpg with 3 cyl and with all 4.
if it's not working then maybe I can figure out how to switch off injectors and somehow kill compression at the same moment. Or cheat ecu or o2 sensor.
Killing compression requires hard mechanical work,
cheating electronic is a lil easier i guess

You should really read up on the forums. We've had a few good threads on cylinder deactivation. There is a good reason nobody here has done it yet.

well... I'll do it.

Good attitude. Maybe you'll be the first.

Be sure to tell us how it goes for ya.

If you lived by me I would help, but when you do it I would recomend getting access to a scanner and see what the difference in Millivolts for the O2 sensor as you do it. Then trick the output of the sensor so it will not see the difference in O2.