i have no spark at the plugs
Maybe you should replace them.
Replacing the spark plugs will not cause the spark to magically reappear. Have the ignition module tested at a local auto parts store. This is a free service at O'reilly Auto Parts.
Have the coil tested also. Check the distributor cap and rotor to see if there are any burn or carbon marks at the center electrode of the cap and rotor.
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