Hello there!
When was the last time the engine was tuned up? No, not just plugs, but a full tune up! The whole nine yards! Any part of the secondary ignition will do this including the ignition coil or coils! This sounds like a classic ignition misfire! They usually go bad under a load like under acceleration, but can be noticeable at any time. It is very important to have your engine equipped with good tune up parts or you may be causing damage to other components of you car like the catalytic converter which can be expensive!
Possible causes:
Ignition misfire causes by any bad tune up part and or ignition coil or coils.Bad spark plugs, spark plug wires and cap and rotor (if equipped)Wrong tune up parts spark plug, wires etc...
Insulator cracks. Wear. Improper gap. Burned electrodes. Heavy deposits.
The quickest way to check the ignition components, is by looking closely for leaking secondary voltage. Visual look at all the tune up parts to see if you can see any sparks coming from any of the wires or coil (or coils) when the vehicle is running. If not, you can put your hand on the coil/coils and wires when the engine is running and see if you feel any small voltage leaking form the tune up parts. Check spark plug wires by connecting ohmmeter to ends of each wire in question. If meter reads over 30,000 ohms, replace wire(s). ALso, with engine running, spray coils and plug wires with fine water mist to check for shorts.
It will leak secondary ignition voltage from the tune up parts caused by high resistance from carbon tracking if they are bad. This is very common if the tune up parts are not changed regularly!
If any is found, the tune up parts are simple bad an will need to be replaced! If none is found than you can spray a mist of water on the tune up parts when the engine is running and see if that causes the engine to stumble or run rough at all. Again, if it does, the tune up parts are bad and will need to be replaced!
Well, if its more than just one cylinder, I would be willing to bet that its not the fuel injectors. WHat are the chances that two or more of the fuel injectors went bad at the same time.
If its just ignition (which is sounds like to me) all you have to do is replace the plugs, wires, ignition coil or coils, and module. THis is a very simple procedure. Just replace the entire module/coil assemble and plugs all at once.
FUEL INJECTORS The fuel injector assembly is a solenoid device controlled by the control module that meters pressurized fuel to a single engine cylinder. The control module energizes the high-impedance, 12 ohms , injector solenoid (4) to open a normally closed ball valve (1). This allows fuel to flow into the top of the injector, past the ball valve, and through a director plate (3) at the injector outlet. The director plate has machined holes that control the fuel flow, generating a spray of finely atomized fuel at the injector tip (2). Fuel from the injector tip is directed at the intake valve, causing the fuel to become further atomized and vaporized before entering the combustion chamber. This fine atomization improves fuel economy and emissions. The fuel pressure regulator compensates for engine load by increasing fuel pressure as the engine vacuum drops.
Just be sure that all cylinders have good compression.
NO... like I said earlier, if it was just one cylinder misfiring, then I would say that it is more likely to be a fuel injector. However, you said that there is a multiple cylinder misfire code in the computer. This means that multiple cylinders are misfiring. WHat are the chances of two or more fuel injectors going bad at once?... not good.
ASE MASTER TECH
ADVANCED LEVEL SPECIALIST