My IROC just turned 20 years old this year. Within the last 5 months I've noticed my elect. gauge drop below the middle marker, then come back up slowly. Before this, the needle has always been at the middle line. I have also have noticed my oil psi gauge bounce when I'm at idle or low RPM(below 1k). I replaced my 5+ year old battery(was in it when I bought it)with an Optima "Red Top" gel battery yesterday becuase when I went to start the car Tues. morning and got the click,click,click with a dim dome lamp. I replaced the alternator 2 years ago, so I was sure it was probably the battery. I had a load test done on the alt. this morning at Kragen's and they said it was consistant throughout different rpm's with a load or without. However, the gauge was reading correctly throughout the test.

My ? is:
Do I have an intermittant(sp?) drain or short in my elect. system or a bad gauge? Like I said before, I know my oil psi gauge is going bad. I believe it's(oil gauge) mechanical though. I'm not real big on elctrical, so I'm asking for help or advice. Anyone had this or a similar issue? I'd hate to damage this new battery. Thanks, Daniel U

 

You could tap into the signal wire from the alternator to the gauge and read what voltage it has, and compare to the gauge.

 

since all you have done lately is changed battery . i would suspect a broken/damaged/burnt fuseable link . there are 3 in the battery area to a terminal block . insp. is no brainer , look & feel . should be obvious if broken or damaged . feel along wires if you find a soft/mushy spot its burnt . they can be cut back & spliced . they are reddish in color . good luck .

 

TraviZ, thanks. You're always the 1st to post a response. I appreciate the help. I'll try and check both what you're sayind and what UNCLE TOM(thx) have mentioned. Maybe I'm making it harder than it is. Daniel U