under neth the coil packs middle back of engine 3 bolts you will need a 10 milimiter 12 milimeter and 13 i did mine 4 TIMES !!!!
The 1990 Chevy Celebrity engine is distributorless, the ignition is handled by a combination of the engine control module(computer) and the ignition control module. You did not mention which engine the car has. If your car has the 4 cylinder engine the ignition control module is below the intake manifold at the rear of the engine. You can follow the spark plug wires to it. The coils are mounted to the ignition control module. If your car has the V6 the ignition control module is near the starter and again you can follow the spark plug wires to it. Again the coils are mounted to the ignition control module.
Which engine does your car have?
All 1987 to 1990 Chevy Celebrity engines use distributorless ignition. Timing is controlled by the engine control module in conjunction with the ignition module. There is no provision for adjustment.
On the V6 the ignition module is under the distributor cap.
The coils are bolted to the ignition control module, there is no coil wire as such.
I would suspect a failing ignition control module.
the ignition control module is operated by the pcm,the pcm tells the ignition control module when to energize the coils to enable spark
You can replace the ignition control module and the crankshaft position sensor as required.
The 1987 Chevy Celebrity has distributor less ignition. The timing is controlled by the engine control module and there is no provision for adjustment.
The 1994 Ford Aerostar ignition control module is located on the firewall in the engine compartment. The ignition control module will be on the drivers side of the firewall.
Remove the wiring harness from your 1995 Chevy Blazer ignition control module. Remove the ignition control module retaining screws. Reverse the process to install your new ignition control module.
You can find the Ford Focus ignition control module beneath the drivers side dashboard. The ignition control module will be above the accelerator pedal.