If you have VTEC, you might have the B17A. I'm not sure what years the B17 was used. I think it was discontinued before 92, though. If you do not have VTEC, then you do not have a 1.7. It's a 1.8 if you have no VTEC.

I'm pretty sure the igniter runs the tachometer. Check the wiring in and out of it. Might be something loose, frayed, etc.