Something strange has been happing with my 1995 NA. I was blasting out of the toll booths last week and I glanced over at my oil pressure gauge and it was at zero…. OUCH! I figured I had an oil leak, and hard run out. I stopped at the rest area and there seemed to be plenty of oil, but the engine seemed particularly hot.

I crawled over to Autozone, but on the way there something strange happened… the pressure when back into the operating range. I checked the oil again and found it to be a little low- I added a quart.

The pressure has been all over the place from zero to normal the last few times I drove it.


I’m thinking that I have some sludge or something…. ? I’m thinking about dropping the oil-pan and seeing what sort of great stuff I can find in here. Any suggestions on what else to do while I have that dropped? Any other ideas for fixing my problem?


Thanks.


Oh – and I haven’t made any recent changes to the car – just an oil change. I’m almost at 200K miles now.

tell me how the dropping of the oilpan went any slug
win you do it i might kneed to drop mypan aswell

You have a broken oil pressure switch.

exact same thing happened to my car. if it was your pump you'd freak'n know. you would sieze up. but if you guage is just reading zero (now and then) then its definitaly electrical (your pressure switch, you wiring to the switch, or your guage)

the stock OP gauge in our cars is notoriously crappy. My stock gauge was all over as well, but the aftermarket is rock steady (depending on oil temp/revs).
If you can i'd recommend putting in an aftermarket one. I've heard that with the 94+ cars you can access the center pods through the passneger side airbag and save yourself from puling the dash. In the mean time i'd ignore the gauge. Just check your oil weekly and change it on schedule.

There definetly seems to be an oil flow problem though... The dip shows way too much oil when the pressure is low, and the dip level is low when the pressure showes normal. Plus the excess heat when the pressure goes to zero.

Same diagnosis's's's ?

well, LOW pressure with TOO MUCH oil doesn't make any sence. with more in the engine you would have a greater pressure. as for the heat, a higher heat will cause lower pressure (because the oil thins out) but that wouldn't cause it to hit 0. i think you just have a switch/wire/guage problem.

just ensue there is always oil in the tank and i believe you will be fine

^ +1

does the temp gauge actually show the car is running hot? These engine do generate alot of heat, and if your judging it from when you open the hood it can be misleading.

If you believe anything the stock gauge cluster says you my friend should buy my ferrari.

boost and OP were crap...water temp seemed accurate (indicated the same as my AM one)
also the speedo on the 1st gen's is a bit off...can be fixed with a $20 part.

hi or low? just wondering as i haven't noticed a problem yet? (rather i haven't been pulled over yet)

never seen any wiring issues, check the connector at the oil pressure switch, it gets dirty and sometimes breaks off or pops off. We rarely see a faulty oil pressure switch itself, but it does happen. It usually stops working completely though. I would also worry about the oil pump going out or the bottom end of the engine going.

sorry thats what I meant. check the connection on the unit.

It would depend on where the oil pressure is measured. If it's measured high, and there is a backup down low, then the pressure gage is going to show low, but the dip would show high.


I haven't had it drop to zero for a few days now, but it does get low. I show too much oil on the dip still too.

And to answer somone else's question - the engine temperature really does go high - not red line high, but higher than normal.

I'll be changing the oil this weekend. Last time, I got about 3 quarts out after 3K miles, and the dip was showing high like now. I'll let you know what I get this time. I might try one of those detergents that you put in with the engine oil and idle for a while before draining - can't hurt.

ok. here's the deal.

oil quantity, oil temperature and oil pressure are 3 completely different things.
the only time they affect eachother is when you have LOW oil quantity, this can cause HIGH oil temperature, and in turn cause a lower pressure.

so if your reading HIGH after each time, then you see how that is in reverse? and the ONLY way you can fill it to the correct level, then end up HIGH, is if your leaking coolant or fuel into your oil tank. this is a terrible thing, but WON'T cause a drop in pressure.

you understand? your symptoms don't match up with eachother.

yes, hotter fluid does expand but not to the level that it would read way high.

the only connection i can possibly make is your leaking COOLANT into you oil, less coolant makes your engine run hotter, but WOULDN"T affect your pressure.

just keep an eye on your oil level, and your coolant level. drive for a week and report back.

if you only got 3 qts out of it last oil change your running it way low...which would cause your symptoms. make sure your checking the oil level when it's cool and been sitting to get an accurate measure.

sounds obvious but you never know.

how does your oil look? does it turn dark quickly? get milky colored?

also, dont know if this was covered or not, but what oil are you using?

so how did you only get 3 quarts out, yet you have a high reading on your dip stick??????? these 2 things are condredictory.
thats whats making this hard to solve. all your problems contredict themselves.

Thanks for all the input on this everyone...

I was due for an oil change this weekend.

Blink - I usually use 10W-30, but I used 5w-30 today. I also used some 'potions'...

I used the 'gunk high-milage motor flush' that is suposed to clean out your crank case. You put it in a cold engine, idle for 5 mintues and proceed with the normal oil change.

*** OK - I got almost 6 quarts of fluid out - which sounds pretty bad. But, that flush is about a quart. I had added a quart of oil on the highway when the oil pressure dropped to zero.... so the math works out.

I also put in the STP Oil Treatment for high-mileage cars. It's like that honey stuff. I figure, it can't hurt.

So, after my 'special' oil change, the pressure comes up right away and right to the middle.


I also flushed my coolant, and swapped out my radiator today. When I had the car inspected last year, they told me I had some corosion on the radior and would need a new one soon, so I held onto the once from the junk car I tore apart this winter. HOLY CRAP... I can't believe the radiator was doing anything at all - half the fins were gone and the rest flaked off to the touch. See pics below.


Lewman06 and others- I know, the facts don't seem to add up on this one. My theory on the high-dip level, but low pressure reading is that the pressure sensor was above an inclusion. This would cause the oil to build up in the oil pan, but keep the oil pressure sensor dry. I made a picture below... The horizontal line is the sensor and the X is the inclusion. I don't really know where the oil pressure sensor is though, so maybe that makes no sense.


So - I have a (hopefully) clean crank case, fresh oil, fresh coolant and a new radiator. I'll let you know how my commuting goes this week...



Here's my old radiator (new radiator behind).
(IMG:http://www.adamanthony.net/mitsu/rad1.JPG)
(IMG:http://www.adamanthony.net/mitsu/rad2.JPG)
look how brittle: http://www.youtube.com/watch?v=wKh4oTYGM_k

Here's my diagram of the oil pressure mystry:
(IMG:http://www.adamanthony.net/mitsu/diagram.jpg)

And here's the junk I dumped in my crank case -

(IMG:http://www.adamanthony.net/mitsu/potions.JPG)

the pressure sender that the gauge moniters is actually way down by the oil pump.

yea im sure that radiator wasn;t doing you any favors...good luck man and let us know how it turns out.

wow bro. thats a pretty crazy radiator. i know MINE has 130 on it. and since i'm adding new turbos and FMIC i figured get a high flow (to allow cooler temps with the FMIC) and mine seemed just fine. you driving in salt alot or something?