MY FRIENDS CAR IS SHAKING REALLY BAD AND THE ENGINE LIGHT IS ON. SHE TOOK IT TO AUTO ZONE AND THEY SAID ITS A CYLINDER 1 MISFIRE. SHE ALREADY HAD HER FRIEND CHANGE HER SPARK PLUG WIRES AND IT HELPED FOR A LITTLE BIT BUT AFTER LIKE A HALF HOUR OF DRIVING IT STARTED SHAKING AGAIN REALLY BAD AND THE LIGHT CAME BACK ON. WHAT ELSE COULD BE WRONG. DOES IT NEED TO BE RE TIMED OR IS IT AN IGNITION COIL??

You have an engine misfire and I can't read the picture, the code indicates the cylinder that is misfiring, for instance a P0302 means cylinder #2 is the problem cylinder. As to the cause it can be a lot of things.

Most likely it is the manifold converter. If 4 cylinder, you have 1, if 6 cylinder you have 2 manifold cat. converters and probably 1 under car. these do NOT go bad by them self. A misfire in the engine due to spark plugs (motorcraft only) ignition coil, etc....If check engine light on, take it to Auto Zone, etc... and they will scan it for free. Get scan codes.. Po420 and po430 are codes for bad converter. Good Luck

Could be the ignition coil. Also could be a compression problem. Work on the misfire then see if the bad sensor goes away.

the engine light blinks when the engine has a misfire the large auto parts stores will scan it for free a code p0301 is cylinder one misfire a p0306 is cylinder number six

a number one misfire means that the number one cylinder is no longer working as good as it should or is not working at all. The number one cylinder is on the back side of the engine on the passenger side. 1-3-5 are the three cylinders in the back.

Three basic things can cause a misfire.
1. a bad spark plug wire
2. a bad spark plug.
3. a bad injector.

Remove the sparks plug wire from the spark plug and remove the spark plug. Inspect the inside of the wire and the outside of the plug to see if there is any carbon tracking. it will look like black lightning bolts. If there is any carbon tracking replace the plugs and wires.

Check the spark plug gap. It should be around .060". if its over .080" the plug is worn out.

Check for spark with a spark tester.

the fuel injector is a little trickier.

Start with the things above and let me know what you find and we'll go from there.

I’m happy to assist further over the phone at https://www.6ya.com/expert/jeremy_d728a59f986299fa

Misfire could be a number of things:
a) spark plugs - change them if used over 15K miles - inspect/regap.
b) spark plug wires - change them if over 15K miles - inspect
c) ECM (electronic control module) - test with HEI (high energy ignition) tester.

The shaking tells me that the engine is running on less than its normal compliment of cylinders - the shaking is produced by the imbalance caused in the engine by one (or more) cylinder(s)
not firing at all.

The "Check Engine" light probably is coming on due the the misfire condition. Go to Pep Boys or
Advance Auto Pats, where they'll tell you (free) your codes causing the "Check Engine' light to be
lit - the code coming from your truck's computer will probably be one or more of:
P0300 - Random/Multiple Cylinder misfire detected
P0301 - Cylinder 1 misfire detected
P0302 - Cylinder 2 misfire detected
P0303 - Cylinder 3 misfire detected
P0304 - Cylinder 4 misfire detected
P0305 - Cylinder 5 misfire detected
P0306 - Cylinder 6 misfire detected
P0307 - Cylinder 7 misfire detected
P0308 - Cylinder 8 misfire detected
P0313 - Misfire detected with low fuel

Misfire means you need spark plugs replaced. Or spark plug coils.

That's why the whole car starts shaking because its running basically on 3 cylinders and not 4 as supposed. There is no gas compression on the 3rd cylinder because once again the spark plug is "misfiring"

There also might be even a bigger problem which could be the distributor cap where the coils are connecting outside the engine.
once you fix the problem the check engine will turn off immediately

hope that helps.

A P0304 OBD2 code is "cylinder #4 misfire detected". The first place to start is your spark plugs. 1. Check condition and for wear. 2. check the spark plug wires or coil packs(depending on which you have).

I had the shaking problem too, had the #5 coil replaced and the shaking instantly stopped.