Oil Pressure fluctuation

[Kyser]

Recently my oil pressure gauge has been fluxuating alot. Starts off normal then rises to about 3/4(high pressure) while driving. Every so often while im at idle it also drops down to about 1/4(low pressure). Any reasons this may be? I just(as of today) replaced my oil cap due to oil being on the valve cover(hopeing the cover isnt cracked and this fixes it), and I will be replaceing my dipstick in like a week when the local mitsu dealer gets one in. Replacing the oil cap didnt help with the flux in pressure so Im not sure what to do next.

~Lyle

 

[turbolover2]

Replacing the cap or dipstick won't help with an oil pressure problem, oil pressure is generated by the oil pump, and is all internal. But it doesn't sound to me like you have a problem. At idle, the pressure is lower because the pump is spinning slow (the timing belt spins the oil pump). The higher the RPM, the higher the pressure goes. 3/4 on the stock gauge sounds about right for cruising. As long as it stays in the limits of the gauge, I wouldn't worry about it. In short, it's supposed to fluctuate with a change in RPM. But you could always swing by a DSM shop and have them put an oil pressure gauge on it and test it so you're 100% sure.

 

[Defiant]

Cut a piece of duct tape so that it's a circle roughly the diameter of the oil pressure gauge face. Place on plastic gauge cover. With a felt pen, write on it in bold lettering, "WATCH THE TRAFFIC".

DSM oil pressure just looks weird. Partly because of the iffy sender (which is how old on your car now?) and partly because they measure it right at the oil pump outlet. I guess they're not too concerned about what it is out at, say, maybe the BEARING GALLERIES or someplace trivial like that.

Also, the connector on your sender probably doesn't have the most secure contact after all these years.

 

[Kyser]

Where is the sender anyhow, It just started acting up so maybe its loose or something but I dont know where to look or what im looking for. Thankfully you guys dont seem to worried about it.

~Lyle

 

[turbolover2]

Originally posted by Defiant
Cut a piece of duct tape so that it's a circle roughly the diameter of the oil pressure gauge face. Place on plastic gauge cover. With a felt pen, write on it in bold lettering, "WATCH THE TRAFFIC".

. Funny.


The sender is on the drivers side, front of the motor. Right by the oil filter.

 

[BUCK]

Those Oil Gauge indications sound completely Normal to me - per the owners Manual on my '91. Below the Low mark is Normal at idle oil Pressure per the Manual - Piss-poor indication engineering but...

 

[Kyser]

Just seems weird that this is the first time Ive noticed it. I mean not that I study all these gauges all the time but I would have figured that I would have seen it move before now, ah well. Guess Ill just check the sender and deal.

~Lyle

 

[Defiant]

Yeah, thinking about your car or your golf swing will drive you nuts.

The sender for the oil gauge is the larger of the two on the housing the filter screws onto. The smaller one is for the Too Late light. They're the only two things down there that have wires going into them.

Wait'll you find out what they get for the pressure sender, and that it's a dealer-only item.

 

[BUCK]

Pressure Gauge Sending Unit (Gauge Bell) available now from Bumper to Bumper in the aftermarket - It was about $40 if I recall correctly - They actually seldom fail - It's the little Pressure Switch that needs to be installed with a Special Socket that fails often.

 

[Defiant]

Jesus, $40 for a $10 sender. owtch.

O well, at least they're out there.