My problem started after taking my car for an oil change to Jiffy some time ago. It hadn't done this before but right after the service, I noticed that the oil pressure started to go up and down irratically. It did this after warm up, then after some time(weeks) it eventually just stayed past 80. So my guess was the sending unit, ok so Ill just replace it and get an aftermarket gauge in the process I thought. I haven't replaced the sender nor the gauge to this day. Not too long ago it sort of returned to normal, I don't know why. Right now, the pressure still acts irratically like before. What do you guys think? I should just replace the sending unit and the gauge right? Will this solve my problem or are there other things to consider?

 

Sending unit is the first thing I'd be suspicious of. They go bad quite a lot. I would NEVER trust the gague to read accurately but it will usually read consistently if the sender is in good working order.

 

Guage on my bird is screwed 2. Shows 40# when I start the car and then goe's down till it hovers at 0# at idle after the car is warmed up. Then after it's driven for awile it returns back to normal pressure. Been like that 2 years now and never have had a problem.

 

Thanks for all your help. I did think it had something to do with the sending unit. I will replace and see what happens. Is it hard to wire it up?

 

No "wiring up" to be done. It just plugs in.

You might find that the wire is just loose on the SU. That would produce the symptoms you describe.

I wouldn't fool around with an aftermarket gauge, if it was me. The absolute value of your oil pressure isn't important, unlike some of the other gauges (speedo for instance); i.e. whether it's "about 50" psi, or 51.3 psi, is trivial. What's important, is if it suddenly changes, or fluctuates while driving, or the like. The stock gauge, however inaccurate it might be, provides entirely enough information for almost any use.... but especially street type use.