I have a 91 Civic Si. Started a couple days ago where the car kept cutting out on me any time I hit the gas and I was below 3000 rpms. Started to steadily get worse to where it would stall at idle and just to get moving again I would have to rev it to at least 3000 rpms for it not to stall. Now the car has trouble starting but before it would start and run fine cold then get worse once it warms up.

I suspected a fuel pump issue and test the fuel pressure and found it to be 5 psi low so I replaced the fuel pump. This did not fix the issue so after some googling I went to the ICM. I replaced the ICM and tested the coil with a scope I was not seeing the correct signal from the ICM to the coil I should of been seeing. As for the coil the resistance test were good. I have also replaced the cap and rotor at the same time as the ICM and I seem to of created another issue. The car has extreme difficulty starting and once it starts it well not idle and the car runs very ruff and acts like its off timing. I set the #1 cylinder at TDC to verify the new rotor was installed correctly and pointing at the #1 cylinder on the cap. I'm now at a complete loss as to what could be causing this issue. Any help in direction would be appreciated.

Thanks!

 

Could be many things at this point. Sounds like a very bad vaccuum leak. Guessing spark plugs are good? I would test the compression on the cylinders. Then i would start at vaccuum lines making sure their not cracked or not hooked in. Then i would check your intake manifold for leaks including the iacv and fitv, the other sensors hooked onto while checking the sensors statistics and make sure they are working.

 

sounds like the ignitor in the distributor…