Where is number 3 cylinder - 2000 Mercury Sable

Dodge use a system called a "Lost Spark Ignition". Basically each coil fires two spark plugs on two different cylinders at the same time every time. One firing for the ignition stroke and the during the exhaust stroke on the other cylinder. Simply, a spark fired every other stroke on every cylinder. That means it only needs 3 coil packs on a V6 engine.
Your firing Order is 1, 2, 3, 4, 5, 6. Cylinder numbers are set as Odds and Evens. Stand with the belts and pulleys nearest to you. The cylinders on the Left side are the Odd numbers and the cylinders on the Right side are the Even Numbers. The cylinder on the LEFT side nearest to you is number 1. The middle one is number 3 and the one furthest away is number 5. The cylinder on the RIGHT side nearest to you is number 2. The middle one is number 4 and the one furthest away is number 6.

On some French engines they number the cylinders backwards compared to everyone else. Citroen cylinder 1 nearest the gearbox/Transmission end So number 3 will be nearest the belts and pulley at the opposite end. Almost every other manufacturer does not use this numbering system.

There should be a coil pack for each spark plug so you should have 6 in total, 3 each side. If the coil packs are numbered that number will most likely refer to the cylinder it is for. Coil pack Number 1 is for Cylinder 1, Coil pack Number 2 is for Cylinder 2 and so on.
The cylinders are numbered like this. Stand with the engine beltsand pulleys nearest to you. The RIGHT side of the engine is the ODD numbers and the LEFT side of the engine is the EVEN numbers.
Number 1 is the cylinder nearest to you on the Right side. Number 3 is the middle cylinder on the Right and cylinder Number 5 is the one on the Right that is furthest away from you.
The LEFT side is number 2 nearest to you, Number 4 in the middle and number 6 furthest away from you.

Firing order is correct, (1, 3, 4, 2). Cylinders are numbered as 1, 2, 3, 4. Number One cylinder is nearest the belts and pulleys and number 4 is nearest the transmission/gearbox end. Stand in front of the car and face the rear of the vehicle. Cylinder 1 is to your left and Cylinder 4 is to your right.

Since you don't say if you have 4 or a 6 cyl, I will give you both.On a 4 cyl count from the front of the engine. The belt pulley is the front.On a 6 cylinder, one bank of cylinders is more forward that the other. On the forward bank the the front cylinder is number 1, so the front cylinder on the other bank is number 2. So number 3 is next to number 1. The second cylinder on the forward bank.

One thing you didn't say you replaced was the plug wire. That could also be the problem.

STANDING IN FRONT OF CAR.CYLINDERS FACING YOU FROM LEFT TO RIGHT IS 1 2 3 THIS INFORMATION I GAVE YOU FOR THE 3 CYLINDER 993 CC ENGINE. DRAW A CIRCLE ON PAPER WRITE DOWN THE NUMBER 3 ON TOP OF CIRCLE AND NUMBER 1 AND 2 UNDER THREE THATS YOUR DISTRIBUTOR WIRE LOCATION.NOW IF YOU HAVE THE 1295CC 4 CYLINDER ENGINE.STANDING IN FRONT OF CAR CYLINDERS FACING YOU LEFT TO RIGHT IS CYLINDERS 1 2 3 4 DRAW CIRCLE ON PAPER WRITE NUMBER 4 TOP OF CIRCLE WRITE NUMBER 1 BOTTOM OF CIRCLE.ON LEFT CIRCLE WRITE NUMBER 2 AND FROM RIGHT OF CIRCLE WRITE NUMBER 3 THATS ALL SPARK PLUG WIRES LOCATION ON DISTRIBUTOR WHILE STANDING FACING THE FRONT OF THE ENGINE.

Firing order and cylinder numbering - all 3.0 and 3.8 engines:


Firing order:

1-4-2-5-3-6


Cylinder numbering:

• Windshield side
  1--2--3
  4--5--6
  Frt. Of vehicle

Coil numbering:

• • --4 PIN--
    ----------------
    --1--- 2--- 3--
    ----------------
    --5--- 6--- 4--
    ----------------
    
    
• NOTE the irregular sequence on the 5-6-4 side. Weird, but that's the way it is.

Cylinder numbering for your engine is 1-3-5-7 on the left hand bank and 2-4-6-8 on the right hand bank (passenger side). To be sure where number 1 is look across the cylinder heads number 1 cylinder is always the head that is furthest ahead towards the front of the vehiclek, then count 3 cylinders back on that side, should be left, and that should be number 5. pull the spark plug first and check it and at the same time pull number 3 's plug and swap the coils from 5 to 3. If the plugs are bad replace them all. Then run the vehicle and see if the misfire code followed the coil to number 3, if it does you know you have a bad coil, they usually run about 90 - 100 bucks each, that is if the plugs or wire wasn't the problem. hope this will help you. good luck.

For the 3.0L on the 1998 Mercury Sable:

Cylinders:
........(back)
1.........2.........3
4.........5.........6
........(front)

Ignition Coil:
(back)
5.....1
6.....2
4.....3
(front)

Let me know if this helped, or if you have additional information or questions. Feel Free to contact me at FixYa.com!