91 CRX DX with almost 250k and original engine. I have only had it about 6 months, so I don't know how many of the components have been replaced but they all look pretty old so I'm going to assume none in the last 50k or so. I've seen a few posts from users with problems with their tachometers either bouncing all over the place, or not working at all, but nothing that quite described the problem I'm having.

When I start the car, the tachometer reads what it should at startup and goes back down to idle fine. It sits steady and stable at idle. The problem is that when I rev it/when I'm driving, it doesn't go up very much. By ear, I'm probably getting it up around 6k rpm, but the tach doesn't read much more than 3. It moves very slowly and is not reading the rpm accurately. If I blip the throttle sitting in my driveway, it hardly moves at all.

The solutions I've seen so far are to check the dizzy/igniter/plug to the gage. I haven't had a chance to work on it since reading those, but plan to tonight after work. Is there anything else I should check while I'm under the hood that might cause the tach to read so low?

 

Nothing?

 

It might just be toast. I replaced just the tach portion in my old 91 CRX si about 2 months ago. It would sit a 0 rpm's when the car was idling and would jump up slowly and jerky when I started to drive. Replacing it worked perfect, no issues.

 

I took the cap off the dizzy and tapped on the icm yesterday and it now works normally up to about 3k, but still gets sluggish and inaccurate beyond that. I'm leaning toward believing it's something to do with the distributer / ignition control module

The distributer could use replaced, but that's a pretty expensive option if it turns out not to be the source of the problem. I'll look into the gage and its connections first.

 

-Update-
Tack randomly works now. Starter crapped out yesterday. Thanks for the help haha