Ok I know for a fact now that my temperature guage is giving a false reading, mechanic figured out htat when the guage says 220, the car is really at 180, also my rpm needle keeps twitching, is there somthing screwed up in my whole guage setup or what???? Please leave detailed suggestions!!!!

 

there is somethign screwed up in every thirdgen's stock gauges, they all bounce up and down, react too slowly, or just generally read the wrong information(like in your case, temperature).

get some autometers

 

www.autometer.com take your pick. Great gauges for any stlye of budget.

 

There are only 3 parts to the stock temp gague. The sender, the gague itself in the cluster and the wiring between them. The sender is a single-wire type deal screwed into the driver's side cylinder head between the #1 & #3 exhaust ports. I'd try replacing that first- they often go bad. While you are at it, test the gague- with the temp sender wire unhooked it should read as cold as the gague will go. Then if you ground the wire it should peg the gague full hot. This still doesn't guarantee that the gague is calibrated correctly but it will give you a basic sanity test.

Last, and this is something I have found on many GM cars, especially 3rd gens...... try reseating the gague cluster in the dash. It's got a quick-connect at the back of the cluster that plugs into a receiver when you push the cluster into position and carries voltage to all the gagues. Don't know why, but sometimes this connection gets flaky and the gagues read "funny"- floating around, reading high, reading low, etc. Take it out, clean off the contracts as best you can and reseat it.

 

Since new (1983), the oil guage has done a constant Irish Jig. If there was a bad bearing, the engine would have given it up ages ago. Changing the sender was a waste of money. The repair lasted only a few weeks. It seems plausable that when a spec of dirt gets into the sender, it stays. I have since put the factory one back on the engine.
The sender is mounted on some lengths of brass piping, in a horizontal position. Not very smart. Should be vertical; threads pointed down, towards the engine. This way, any spec of dirt would run out. Maybe I will play with it.
Note: I just reinstalled the Neihoff replacement unit. It has been sitting in the basement for years, with the threaded portion pointed down, into the bottom of the box. Guess that the dirt had found its way out of the sender. Works fine, just as it did when 1st installed years ago. Next step is to figure out how to get the installed sender to point down, so it will stay clean.