Car won’t go, it shakes

 If a car shakes when the gas petal is stepped on and it won’t go fast, then you probably have an ignition problem. This is generally a problem caused by a spark plug wire arcing to the engine ground. The other possibility can be a bad spark plug. This is a 1996 pontiac grand am, 2.4 liter engine with a coil pack. This means that there are no spark plug wires but instead an intermediate plug that fits between the plug and the coil. If a car stumbles when the gas petal is stepped on it is because the spark is grounding to the engine instead of reaching the spark plug. If your car has not had a tune up lately now would be a good time to do that. To find the problem first the spark plugs need to be removed.

 In the first picture you can see the cover that says 2.4 L twin cam on it. There are four bolts that will need to be removed. When they are removed the cover will come off and looks like the picture below.

Be careful not to let the pieces that surround the bolts above and below the cover to fall in the engine valley. On the bottom of the cover is the large white coil pack. The four intermediate spacers that sit on the bottom of the coil pack replace the usual spark plug wires. The spacers are simply a rubber boot with a spring in the middle that connects the coil to the plugs. 

 The label below located under the hood tells the tune up specs and will have the spark plug gap on it. This 2.4 liter engine needs the spark plug gap at .060 thousands of an inch.

 Below in this picture is where the spark plugs are located. This is the valley below the coil pack. Simply remove the spark plugs from the engine then look at the bottom of them. The spark plugs should be clean or have light brown coloring on the electrode tip. If any of the plugs are wet or black they have been arcing and that is the cylinder to look at.

If the spark plugs look good and the spark plug gap is correct, remove the spacers from the coil pack. If you look inside the spacers you will see a spring. Use a pick or a needle nose pliers to remove the spring. It will only come out of the larger hole end. When the spring is removed stretch the spring out to make it a little longer. Over time the spring can compress and won’t snap over both the coil and plug. This will cause the spark to ground out and your car to stumble and not go. Reassemble everything and you car should be ready to run.