car not cruising right

hi, i have a 06 corolla le 4 cylinders. when i bought it it was running good but nowadays it seems to slow down when i'm not pressing gas. When we bought the car, i used to go far without pressing gas and just slow it down on it's own. But now it slows down more than usual.
It seems like the RPM is making it slow down. Could this have anything to do with the transmission. ???thanks

Manual or auto transmission? But I assume an auto based on your thread.

Also need to know the mileage and if you were the original owner. Finally, any recent maintenance done...oil change, new plugs, transmission service? All this info helps us diagnose your problem.

A general sluggishness can be most easily caused by a change in the gas formulation. Those winter ethanol blends have less power than the full gasoline that you may be used to. Your fuel economy can go down as well...literally less bang for your buck! You also may have some fuel buildup and oil sludge buildup. Try running some fuel treatment such as Chevron Techron or Seafoam through the fuel and intake to help remove that buildup.

Another common cause is buildup on the spark plugs, or a problem with other ignition system components such as an ignition coil. Check the plugs for proper gap and wear. Since yours is an '06 I doubt you'll be due for a plug change...OEM plugs are typically good for 100k+ miles.

Your car has what are called "coil on plug" meaning each spark plug has its own electrical coil to make it spark. If one of these is getting old or doesn't have a good electrical ground to the engine (through the spark plug), it can cause a weak or intermittent spark. Have those checked for the correct resistance.

Finally, it is common in the colder months for a car's gas tank to accumulate some water from overnight condensation. This is especially problematic if the temperature drops alot and the gas tank is nearly empty. If the weather has been very cyclic lately, you might try some Heet fuel additive to reabsorb the water into the gas and get it out of the tank. Keep the tank full when you can to avoid this.

Hope this helps!

Before changing your engine or transmission lift the front end of you car and turn the wheels and feel the resistance, if you notice it takes more effort than usual to turn the front wheels you could just need a caliper service in which you would remove the pads and sliders and clean the bracket and lube the sliders. If your brakes cannot move freely it may cause exess resistance therfore when you take your foot off the gas it will start to slow the car and make it feel sluggish. Routine caliper service is allways a great idea on any model car it will prolong the life of your pads and discs and improve your fuel economy.

Many things can affect coasting distances..

if one or more of your tires are under inflated, or if you recently had installed different tires that aren't low rolling resistance tires..

brakes dragging

front end out of alignment

rear end out of alignment

CV shafts not turning freely

wheel bearings wearing out


I usually work my way from the least expensive potential cause up to the most expensive...