Hello everybody! This is my first posting on this site. I have a question regarding the Tach function on my 89 L-98 coupe w/ auto trans. Here goes: My tach readout bounces around like a yoyo when I cruise at a fixed speed. For example, I might be doing 50 mph and the tach will read 1500 rpms, and then jump to 2600 then go back to 1400, then up to 1900, etc. It just doesn't stay at a fixed RPM display. Anyone have a fix for this problem? It makes me nutz!@

Steve

Hm... with a handle like that, are you sure you can even see the tach?

bada-bing.

Sorry, had to do that.

Now, it's time for some real help! The tach filter has taken a dump. It's a capacitor on the tach lead that filters out the square waves of the HEI so that the tach can read them correctly.

IIRC, Ecklers sells a replacement kit for a reasonable price.

Bogus, you sure know your stuff. I wish I had half the knowledge of the bogus, I would be the poop diggity. So my question is the tach the only thing doing this?

hm... if the filter fails, the only thing that notices is the tach. I don't think it effects the ECM, it get's its info from somewhere else... I would have to check the schematics to be sure.

if you are curious, I don't think it would cause interference or anything,

Sorry to take so long in reply, but the tach filter was the problem. As soon as I replaced it, the tach settled down and runs like a charm now! Thanks for the good advise!~ Now, if I could only find someone to adjust my 89's side windows! I replaced the weatherstripping and now they leak worse than before!!

Quote:

Are the windows not closing far enough, or are they pushing out from the weatherstrip? If you can describe your problem or better yet provide a picture I should be able to help you adjust your windows.