1991 S-10 w/2.5L engine, know the firing order but do not know which connectors on the distributor cap is number 1,2,3,4

Assuming you know the basics of how an engine works the firing order is 1, 6, 5, 4, 3, 2.
Standing in front of the vehicle, facing the rear of the vehicle, the cylinder layout is this. Left side is the EVEN numbers and the right side is the ODD numbers. Number One is nearest to you on the right side. Number Two is nearest to you on the Left. Number 3 is the middle right, Number 4 is the middle left. 5 is back right and 6 is back left.
At the distributor the leads should be fitted in the firing order sequence moving in a CLOCKWISE direction. On some distributor caps the terminal for cylinder One is marked with a number on the top of the cap.
The cylinders Don't fire as pairs they fire in sequence alternating right to left.

need to know what year, make, model and engine is in your car to help.

Firing order 1-3-7-2-6-5-4-8 --------- front ' 1 2 3 4 ' of ' 'distributorless ignition vehicle ' 5 6 7 8

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FIRING ORDERS NOTE: To avoid confusion, remove and tag the wires one at a time, for replacement. Fig. 1: 2.2L and 2.5L engines Firing order: 1-3-4-2 Distributor rotation: Clockwise
Fig. 2: 2.6L engines Firing order: 1-3-4-2 Distributor rotation: Clockwise
Fig. 3: 3.0L engines Firing order: 1-2-3-4-5-6 Distributor rotation: Counterclockwise
Fig. 4: 3.3L and 3.8L engines Firing order: 1-2-3-4-5-6 Distributorless Ignition System
Fig. 5: Distributor cap terminal routing (view from top of cap) - 3.0L engines

I do not have a breakdown diagram for a distributor, but just the firing orders and description of ignition system for the Dodge Colt and related models (based on Chilton manuals) if that's what you're looking for: FIRING ORDERS Fig. 1: 1990 1.8L SOHC Engines Firing order: 1-3-4-2 Rotation: clockwise

Fig. 2: 1.6L DOHC Engine Firing order: 1-3-4-2 Distributorless Ignition

Fig. 3: 2.0L Engine Firing order: 1-3-4-2 Rotation: clockwise

Fig. 4: 1.5L Engine Firing order: 1-3-4-2 Rotation: counterclockwise

Fig. 5: 1993 1.8L Engine Firing order: 1-3-4-2 Rotation: counterclockwise

Fig. 6: 2.4L Engine Firing order: 1-3-4-2 Rotation: clockwise

To avoid confusion, replace spark plug wires one at a time. --- Distributor REMOVAL & INSTALLATION Although the distributor can be removed from the engine no matter which cylinder is about to fire, it is a good idea to have number one cylinder at TDC before distributor removal. 1.5L, 1.8L, 2.4L SOHC Engines

1. Disconnect the negative battery cable.
2. Disconnect and tag the spark plug wires from the distributor cap.
3. Disconnect the distributor harness connector.
   Fig. 1: Ignition system for the 2.0L engine
   
   Fig. 2: Ignition system for the 1.5L engine
   
   Fig. 3: Ignition system for the 1992-93 1.8L engine
   
   Fig. 4: Ignition system for the 2.4L engine
   
   
4. Loosen the distributor retaining bolt and remove the distributor from the engine. To install:
   
5. Rotate the engine until No. 1 cylinder is at TDC on its compression stroke. NOTE: Be careful not to turn it to the No. 4 cylinder TDC on its compression stroke by mistake.
   
6. Align the distributor housing and gear mating marks.
   Fig. 5: Ignition system for the 1990 1.8L engine
   
   Fig. 6: Distributor installation for the 1990 1.8L engine
   
   Fig. 7: Distributor installation for the 1992-93 1.8L engine
   
   
7. Install the distributor into the engine, while aligning the fine cut (groove or projection) on the distributor flange with the center of the distributor mounting stud.
8. Install and tighten the distributor retaining bolt.
9. Reconnect the distributor harness connector.
   Fig. 8: Distributor installation for the 2.4L engine
   
   Fig. 9: Distributor installation for the 1.5L engine
   
   Fig. 10: Distributor installation for the 2.0L engine
   
   
10. Install the distributor cap and spark plug wires.
11. Reconnect the negative battery cable.

For the 2003 Dodge Caravan (and Grand Caravan) ALL 3.3L V6 Engines (including the Flex Fuel): Also for 3.8L V6 Engines:

Firing Order:
1-2-3-4-5-6

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

Ignition Coil:
.......(back)
electrical connection
...........|
..........V
5........1........3
2........4........6
.......(front)

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

You didn't post your engine size so please use the appropriate diagram:




GM (Cadillac) 250 (4.1L) V8 .GM (Cadillac) 273 (4.5L) V8 .GM (Oldsmobile) 307 (5.0L) V8 .GM (Oldsmobile) 350 (5.7L) V8 w/EFI.Engine firing order: 1-8-4-3-6-5-7-2 .Distributor rotation: counterclockwise





GM (Buick) 252 (4.1L) V6 .Engine firing order: 1-6-5-4-3-2.Distributor rotation: clockwise





GM (Cadillac) 368, 425, 472, 500 V8.Engine firing order: 1-5-6-3-4-2-7-8.Distributor rotation: clockwise





GM (Cadillac) 429 V8.Engine firing order: 1-8-7-2-6-5-4-3.Distributor rotation: clockwise

For all Dodge V8 truck engines, the firing order is 1-8-4-3-6-5-7-2. For all Dodge V6 truck engines, the firing order is 1-6-5-4-3-2. For Dodge inline 6 cylinder engines, the firing order is For all Dodge 4 cylinder engines, the firing order is 1-3-4-2 All dodge distributors rotate clockwise.


look at your distributor cap while standing on the driver's side of the vehicle.
Start at number 1, which is labelled on the cap, and go
clockwise

Good Luck

Firing order is 1-8-4-3-6-5-7-2 Cylinder numbers looking at engine from front Left Bank 1-3-5-7 Right bank 2-4-6-8 Distributor has clockwide rotation,