I have a '90 (S5) N/A that I recently did a motor swap on. The car ran good and idled perfect but would start to "misfire" at about 2500 rpm. I have gone through all the diagnostics... fuel, air, ignition, compreesion, etc. and everything checks out good. The only thing I could think that could be the problem is the timing.

I wanted to check the timing but I couldn't get my timing light to fire on L1, L2, T1, or T2. At first I thought it was the timing light so I tried to adjust the timing by ear but I think I made it worse and now the car won't start. It will get close but then stall.

So, I tried a different timing light and had the same problem. Both lights work just fine on my '86 RX-7 so I don't think it's the light. I checked my igniter resistance and voltage, CAS resistance, and checked continuity and voltage of all pertinent wires at the computer. No broken wires and all resistances are in spec. I also swapped the entire ignition sytem over from my running '86 to rule that out completely.

I can literally remove a plug and watch it spark while turning the engine over and pulling the timing light trigger and the light won't fire.

Any idea why my timing light isn't working? Any ideas on how to safely time the engine without a light?

Thanks for the help...

 

Are you sure the timing light is car powered? That is, does it have leads that connect to the battery. The FSM states that as a requirement.

 

Great question. Yes, it's a vehicle powered inductive timing light

 

If you install the CAS itself per the FSM, and do it RIGHT and not screw things up and get all cofused, the timing should be withing five degrees of being correct.

You just align the fixed pin on the front cover with the first hash mark on the pulley.

Then pull the CAS out.

Align the fixed and moving marks on the bottom of the CAS.

Remove the top, black cover that is held with two screws.

Take note of where the internal moving parts are in relation to the fixed parts in the top of the CAS when the parts on the bottom of the CAS are aligned.

Insert the CAS into the front cover.

Turn the CAS's body til the fixed and moving parts in the top area are now aligned as they were when the CAS was out of the engine. Done.

As for fixed and moving parts in the top of the CAS, a good ref point is the corner of one of the black reluctors and one of the two pointers on the top of the rotating shaft. When the bottom marks on the CAS are aligned, you'll find the pointers in the top of the CAS are opposite the corner of the reluctors.