So the battery on my Evo IX died this weekend and I replaced it immediately. However when I hooked up the new battery and turned the car on I noticed my oil pressure via my defi gauge was really low after the car warmed up. On the old battery my Evo's oil pressure would linger around 15 to 18 psi at idle. Now with the new battery it's around 10psi sometimes falling a tad below. When I drive the car the oil pressure it perfect, its only at idle it's acting strange. Has anyone else experienced this?! Thanks in advance.

 

Did you jump the car and possibly reverse the terminals? Possible that that may have messed with your gauge. Also how old is the sensor and sending unit?

 

Battery terminals are properly connected. the oil pressure light on my dash isn't on or anything. I just noticed my defi gauge reading lower than it has previously. That's my concern.

 

Possibly the sending unit to the guage not functioning properly?

 

Thinking you dont have a problem at all. My gauges read around 10psi hot at idle as well.
Could be a number of factors, hotter temps out side, running a thinner oil, due for an oil change all effect idle pressure. You dont have a problem at rpm and its not fluxuating your good to go. If you had a knock, or oil pressure was down across the board then you would have a problem. Thinking you just noticed it because you started focusing on electrics in the car after the battery died.. I say they are unrelated.

 

I was thinking that too, I just thought it was weird all this occured after a simple battery change.

 

off topic here, but since you guys are all running an oil pressure gauge Id like to ask, do you guys recommend a 100 psi gauge or 150 psi gauge?

 

Mine goes up to 150 but I've never had it even remotely close to that high. When I'm driving normally I'm right around the 60psi mark. When I'm at the track I'm between 75 and 80psi.