I have a 1998 Honda Prelude automatic transmission..i am haveing some problems with my rpm tach on my car.. Lets say im goin speed limit or what so ever. im around 3,000 rpms or so. the rpm needle starts tweaking out a big..start jumping up a lil back and forth for a bit and goes back to normal..then it would do it again later but this time it would drop to 0rpms... i fastly shift my tranny to nutral to see if i can rev it up for some rpms and nuthing. give it about 5 sec and the car goes back to its 3,000 or so rpms..and then goes normal....I thought it was my negative battery terminal that was bad and no good ground so i bought a new one and installed. once i did that it never made the car drop to 0 rpms anymore.. NOW the rpms tweak out abit just moven slightly up and down and returning back and acting normal again.. like i explained at first. My tranny is new so i dont think its that.
Another thing When i step on the gas to pass up someone..once i hit around the vtec level my rpm needle goes hella crazy..it redlines and goes back to what it should be..so im stepping on it and the car is still moving but the car sounds like its redlining in and out... The rpm needle goes way pass the 9,000 rpm line. it almost goes all the way back around..seems like it tweaks way to much! Do u think i might need a New Gauge Cluster?.. I need help with my car..so if anyone knows something plz let me know..im hating my prelude right now..even though i love preludes. Thanxs,
-JC

 

Dude you really like the word tweak. lol

Try and organize your thoughts and space your sentences out next time also.

You still have a bad ground somewhere, try checking the ecu ground on the thermostat housing.

 

Or loose battery connections, that was my problem.