I'm not a mechanic but it sounds like there has been a mixup involving your spark plug wires , either at the coil pack or at the spark plugs
Replace the spark plugs.
replace spark plugs and wires
the transmition ,is probably not adjusted to the spark plugs,or their not the right spark plugs
You probably mixed up the firing order.
Have you checked that the coil packs are all plugged in? Replace your spark plugs? Heck I would replace the plugs just to rule them out as the fault. I would need a little more information to answer this fully.
water in the fuel bad spark plugs bad plug wires bad coil
Check/replace Rotor Check for spark at plugs
I would replace the spark plugs after 50K, the wires and plugs again at 100K.
The spark plugs on a 1999 Mercury Cougar are located under the cover of the engine. The spark plugs should be changed approximately every 60,000 miles.
The manufacturer recommends that the spark plugs are changed every 30,000 miles. Many individuals have experienced a much longer life for the spark plugs.
30000 miles
The spark plugs on a 1999 Mercury Cougar are located under the cover of the engine. The spark plugs should be changed approximately every 60,000 miles or so.