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The firing order for a 1990 Cougar 3.8 is 1-4-2-5-3-6. The number one cylinder is the front one on the passenger side.
8 spark plugs
arnt all spark plugs just below the valve covers on all engines ???
how the sequence of spark plugs goes on the engine of 1990 Toyota cressida
They are right there on the top of the engine.
The 2.3 liter 4 cylinder engine has ( 8 spark plugs ) , twin plug ignition system The 2.9 liter and 4.0 liter V6 engines have ( 6 spark plugs )
you are not getting spark. this could be from a bad alternator, bad spark plugs, bad spark plug wires, or bad engine coils. The spark plugs and wires are the cheapest so try putting in new ones of those first.
The only time I've seen cracked spark plugs was putting them in or taking them out with the socket not perfectly straight.
5/8
check/replace spark plugs
To replace the spark plugs on your Celebrity requires a 5/8" spark plug socket, short extension and either a ratchet or breaker bar. First remove the spark plug wire then use the socket to remove the spark plug. The spark plugs should have a .045" gap. Replace the spark plug and reattach the wire. Continue until you have replace all of the spark plugs.
Right up under the tank.