What is the timing order for a 91 Pontiac Transport?

The firing order for a 1991 Pontiac Transport depends entirely on the engine it has. Pontiac Transports of that year used several different engines. You must know the engine size (e.g., 2.5L, 2.8L, 3.1L) to determine the correct firing order.

Once you know the engine displacement, you can find the firing order in your owner's manual or by searching online using the engine code (often found on a sticker on the engine itself). A reliable source for this information would be a repair manual specific to your vehicle's year and engine.

Without knowing the engine type, I cannot provide you with the firing order.