While drving my 89 towncar, its starts to break down like its bucking. Seems like a spark plug is not firing or a wire is bad. I just had it uned up about 3000miles ago and don't know what the issue is. can you help me?

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I would check for spark first with a spark plug tester. They are about $10 bucks and very easy to use. Then check all spark plugs for massive wear, and then check all spark plug wires for breaks or burn holes from motor. If not any of these, then I would check to timing belt. Once you diagnose these things, get back to me and we'll go from there. Good luck. P.S. Did the check engine light ever come on?

Have you checked cam timing?If it has jumped a tooth or two it will not start.

I don't have enough info to give you a specific answer so I've listed a bunch of possible problem that could cause your engine to roll over but not start.
Check the battery and connections, a weak battery or bad connections can cause a weak spark and stop the engine from firing.
Fuel pump or fuel filter, low gas pressure can cause to lean of a air/fuel mixture for the engine to start.
Bad gas, old gas or water in the gas can stop the engine from firing.
Bad or fouled spark plugs, could be caused by bad gas.
Ignition wiring problems, can cause weak or unreliable spark.
Bad, poorly connected or misconnected spark plug wires. Even 2 wire out of order can stop the engine from firing.
Oily spark plug wires, can cause the spark to fire at the wrong cylinder or misfire.
Worn, damaged or wet ignition components.

You might want to check the coil after the engine has wormed up to see if it is breaking down and not fireing the spark plugs. Use an in line spark tester to check between the coil and the spark plug wires to see if it is firing the plugs after the engine has gotten worm. Have someone to turn the engine over while you watch the tester for fire. Hope this will help you.

there are several possibilities. by bogging down do you mean the engine runs smooth but looses power? or does the engine/car start shaking and doesnt want to go any faster? if the engine runs smooth and doesnt seem to be shaking...can you hear a noise from the engine compartment? or a hi pressure noise from the rear of the vehicle - like a vacuum cleaner? if so then you probably have a plugged catalytic converter. if the engine seems to shake the van and looses power until you let up on the throttle slightly then you have a misfiring condition which can be caused by bad plug wires,plugs or a coil breaking down. as you shift up in gears the spark needed to each cylinder is increased and if you have bad plugs,wires or coil the spark wont get to the cylinder when it is needed. see if any of this sounds similar to your condition and request more info from me if ya like. good luck. carefull the converter can cause a fire if it gets too hot!

Check the spark plugs and wires. If the wires are breaking down, the spark can short to ground, and you don't have enough spark to fire the plugs well. You may not be able to see the cracks in the wires. It is better to find a dark place. Raise the hood and start the engine. Spray a little windex or soapy water on the wires. If you see little blue sparks jumping out of the wires, you know they need to be replaced.

Check a spark plug wire fire spark (Autozone has a tool to do this safely for around $10) if no spark test the input wire at the coil, if there is power at the input plug (red wire) Replace the coil!

I had an 85 Bronco II that started bucking sometimes when I shifted into drive or reverse right be for the rear driveshaft went bad.

fuel pump, bad spark pluck, bad plug wire, ignition wires maybe