hi well i just got my 87 iroc fixed about 2mothes ago after she sat for 5yrs with a almost full tank of gas but i paid 1500 to get her fixed by a mechnic and they cleaned several times the gas tank and fuel injectors, flushed an refilled all fluids and just a bunch of other stuff i'll hve to get back to you with that but anyway it runs pretty perfect now with only 27k miles and well iv had this problem with the fuel pressure gauge jumpin back and forth between around 30-60 pretty quickly for about 2 minutes after start up but then the needle wont jump quite as far and rapid and then after about 2 mins of no reving it will sit pretty still at around 40 then after about 7 mins it went all the way down about 20 then i reved several times and it would just to about 50 then shoot back down to around 20. so is this normal for 305tpi irocs to do this and is this a problem or not? also after about 7 mins of just idling it will idle at about 700rpm but on start it will be at around 1000rpm idle. and is 13 ( volts? ) what the needle needs to be on or is it to high or to low? so do i have anything to worry about and if i do do i need to fix this immedily? thx the first pic is right after start up, second is on rev after a few mins, and last is of it after about 7 mins.

13 volts is a normal reading. I don't see a fuel pressure gauge--I see an oil pressure gauge.
I use an after market gauge so my oil pressure fluctuates with RPMs.
Engines idle higher when they're cold.When they warm up,they settle at idle.

(Edit)
My oil pressure gauge is a manual gauge. I don't know if electric gauges fluctuate like yours is doing.

Agreed- you're looing at the oil pressure gague. Your readings are fairly normal, except for the "jumping" part of the description. 3rd gens are notorious for the oil pressure sending unit getting "flaky" in their old age. Might want to consider replacing it- bet it gets rid of the "jumping" needle problem.

Oil pressure isn't contant. Engine temp (really oil temp) and RPMs affect it. In stock condition the oil pressure should be about 40 PSI on a fully warmed up engine, above about 2500 RPMs. Cold engine/oil increases pressure. Lower RPMs (idling) decreases pressure. On a fully warmed up engine about 20 PSI at idle is normal, abut 40 or so revved up to at least 2500-3000.

srry about that i mean oil pressure. i honestly just guessed some things i know some things i dont. i just started actually gettin it to this stuff about 2months ago.