Which engine do you have in the vehicle? They fitted them with an in-line four cylinder and a V6. The firing orders are different for each version. I'm assuming the distributor has NOT been removed and is set correctly!
**Note, Take your time to make sure you get this right!**
The Four cylinder is the standard 1,3,4,2, firing order with number One being the nearest cylinder, (spark plug), to the belts and pulleys on the engine. Use the plug leads as a guide as they should be four different lengths. The longest plug lead to the spark plug furthest away, shortest to the nearest spark plug.
With the distributor cap removed make sure the engine is at Top Dead Centre for cylinder One. Check where the metal tip on the rotor arm is pointing as this is where the plug lead for Number One should go.
Refit the the distributor cap and insert the lead for the Number One spark plug into the hole nearest where the rotor arm tip was pointing. Now refit the remaining 3 plug leads in the Correct Order, (1,3,4,2,) into the remaining 3 outside holes in a CLOCKWISE direction. The centre hole should connect to the coil pack lead.
A V6 engine uses the same setup BUT a different firing order. (See photo). 1,4,2,5,3,6. In the photo numbers 1 and 4 are nearest the belts and pulleys.
Set your distributor as you would for the four cylinder engine, fit plug lead one and going CLOCKWISE fit them as the 1,4,2,5,3,6 sequence.