Why does the oil pressure light come on when the car is put into gear from idle then go off when accelerating?
Oil pressure lights work off the pressure of oil in the engine. When the car is idleing and out of gear the engine is turning a certain RPM (Rounds Per Minute). The speed that it is turning is fast enough to keep the oil pressure at a level high enough not to trigger the light. When you place the car in gear, the engine slows down and thus the oil pressure drops to a point low enough to trigger the light. Once you accelerate, the speed of the engine increases and brings up the oil pressure. Now, the cause of this could be numerous. First make sure you have plenty of oil as this is the least expensive to fix. The oil could be too thick and needs to be changed to solve this change the oil if it's been a while. Finally there could be several mechanical reasons for low oil pressure such as a bad oil pump (not likely), clogged oil lines/ports, worn main bearings, clogged return oil ports from the heads. None of these last things are cheap to fix. However, if it's a motor with clogged oil ports (thick oil, gunk on the inside of the valve cover, etc) there are products that will disolve it that you can flush the motor with and then change the oil. This 'fix' can sometimes cause more problems to crop up and should be used as a last resort. Good luck.
Why does your automatic car jerk when accelerating and coming to a stop and the dash display shows that it is not in any gear?
Well, the daytime running lights are on whenever the car is running and in gear. They're off when you have the headlights on. So, your service light Doesn't come on when the headlights are on?? If you switch the headlights between on and off (with the car running and in gear) does the service light follow?
If by slipping into 3rd gear you mean that it is hesitating to go into third gear you may have an accumulator piston seal broken or a clutch that is getting severely worn out. If you mean that it slips while it is in third gear you need to have the transmission pressure tested to make sure you have the proper fluid pressures in all gears. This should be done by a qualified mechanic on…
What would cause your automatic car to sputter and jerk bad when accelerating in first gear but be okay once it gets to second?
The Trac Off light will come on if you push the traction button located below the automatic gear shifter. If driving and the light comes on, as well as the check engine light, then there is a malfuntion with the system. If low trac comes on, it means just that. You have low traction! Hope this helps :)