Have a 1990 cutlass supreme and was going to do a coil replacement. Easy right? Well no. They are on the under the coolant reservoir and easy enough to reach the top bolt, but how to get to the bottom bolts? More important, once out what is the trick to getting them back in? I am going from the top of the motor. Do I need to go under? It doesn't seem like that would work either. Is there a trick to it? Thanks in advance for any help.

 

Can you remove the coolant reservoir to get to them ?

 

Yes I took off the reservoir however the bottom screws are still out of sight. There also is part of the wiring harness in the way.

 

Update. Looks like it is best to remove the whole module which has 3 bolts with easier access, not just the individual coils, then take off each coil. Gonna try it this weekend.

 

Looking at the coils available for your car I suggest getting the NGKs or AC Delcos. Chinsium brand ignition components have been known to be bad out of the box.

 

So, finally got to the coils and the Haynes manual helped, but wasn't really specific so I will break the steps down. All directions are given from the point of view of looking at the coils.
1. Jack up front of car, we used ramps and remove battery negative.
2. Remove two bolts holding coolant reserve. Remove top coolant line from radiator and plug, we used a golf tee. Move reserve to top of motor out of the way.
3. There are electrical connections on the left and right of the module that holds the three coils. Snap these open and pull back and off.
4. On the upper right of the module plate feel around and remove the 13 mm bolt.
5. On the upper left remove the 13 mm nut that holds on the spark plug wiring loom bracket. Then remove the threaded stud with the 13 mm nut on it.
Now the fun part.
6. Remove Oil Filter and electrical plug next to it.
7. From here you can look up and see the module, you will notice another electrical plug on the left of the module, remove that plug as well.
8. The module bracket is silver and there is one last 13 mm bolt on the bottom slightly to the left of center. It was a bear to get out, finally used a 12 point short reach 3/8" drive with a swivel and extension.
9. From hear the whole module will come out and you can replace the three coils by removing the two 5.5 mm bolts from top and bottom.
Install is reverse. This seems to be more work than it should be, but I hope this breakdown helps someone.
On a side note, car seems to be running better now. Also, we went with the NGK coils.