99 z

Ok so heres the story. My car sits in the garage every winter. I start it every week or 2 to warm it up circulate fluids and stuff. Today I pulled it out of the garage let it run for 30 minutes. When I put it back in the garage I didnt get it parked right so I started it and repositioned it. I noticed the oil pressure guage bouncing a little bit. When I rev it or hold the pedal around 2000 rpm its steady around 50ish. Just bounces a little at idle around 40.

My car is pretty much stock. just headers, catback. The only thing I've done to it lately was trying to tune v.e. with hp tuners back in september. I've since returned the computer back to the previous program that I had in it that ive had for 2 years. Just rear o2 and skip shift deleted. The rest is all the stock file. I was getting the v.e. close but was running out of nice days and time to drive it. I did go wide open throttle with it once while tuning v.e. table towards the end there. It ran awesome and the wideband was showing 11.5- 12 afr while at wide open and around 14.5 everywhere else. So I dont think that would've done anything.

Anyone else have this problem with oil pressure gauge?
Oh and car has 49k on it.

Thanks.

patSS/00

iTrader: (6)

Battery in poor shape could do that. Just sitting or low use in the winter = battery rot.

99 z

I put a new battery in last summer. I was thinking maybe a problem with the sender or guage. Hopefully its not the pump or anything that could be serious. Oil level is good and oil is clean. No weird noises.
Hopefully just the sender. I will locate it and change it when I get time. I was just wondering if this was something common in these cars. Its a 99 so it is goin on 12 years old.

01Ws6ix

Ya mine started doing that about two months ago and still runs fine, I was told on here it's common and is probably the sender, I'm gonna check it out once winters over. Good luck.

1 FMF

iTrader: (1)

it's normal, especially with 5w-30 oil that's hot. Oil pump output depends on engine rpm.
you won't see the gauge bounce at idle when the engine (oil) is cold and thicker,
and raising the rpms and seeing a steady pressure increase and it's above 40psi says everything is normal. It's also normal to have oil pressure drop down to 20psi at a hot idle with 5w30, but as long as pressure jumps up to 40psi and above when you get the rpms up around 2000 then everything is fine. mine does the same thing sometimes, I have an 02 with 57k.

608kZ28

mine does the same thing. steady psi 2000 and above

99 z

Ok so it seems fairly common. This was the first time I've noticed it do that. I'm gonna go ahead and change the sender to see if it goes back to normal. I have some other things to do to it anyway so why not. One of those things being the fuel pump. I noticed that guage bouncing and showing empty at times when I know I had a full tank.

Old age gettin to her I think.

Thanks for the replys.

O2Form

Mine did that after it sat for 5 years. After driving it a few weeks it stopped.

Blackhawk777

Mine's done that since the day I bought it. Is your car by chance an auto? I know for whatever reason the autos show lower oil pressure at idle. I'm also assuming it's the stock oil pump? The above are right though, as long as you see a min of ~40 psi at 2000 rpm all is gravy with the engine.

t/a98

iTrader: (6)

Autos have less pressure because they idle slightly lower. If both were idlieng the same rpm it would have the same psi

drago1217

iTrader: (6)

Mine did this so I changed the sending unit ( which was a bitch but I has the tranny out would be even worse with it in) and it used to bounce pretty bad now its a lot better. Still bounces a little but oils good so not worried about it. But if it is your sender..........hope you have small hands and can rig up an assortment of tools swivels and DEEP 1 1/16

99 z

Well I will be replacing the clutch and hydrolics in the next few months. So I guess I'll get to it then while the tranny is out. I started it a couple days ago and it was steady at 40 while idling. Maybe just a freak thing. We'll see.