oil pressure low

[AB'sLs1]

so right now my oil pressure is always at about 15 to 20 psi unless i get into it then it goes to 40 psi..... when i first change my oil its normal at about 39 idle and 41 stop and go traffic but then after about a month and a half of driving it goes to about 15 to 20 osi like it is now.... my car has high miles(163000) i assume its burning a bit of oil.... my question is should i switch to a thicker weight oil to keep pressure up like 10w-40 or should i try something else like a high milage oil i dont know what your guys thoughts r on that stuff... any help is appreciated


the question is about the oil im not really concerned to much about the bit of oil burn cuz its not doing it badly.... plus i cant afford to change my rings or valve seals right not


thanks guys

[Spaz]

have you run that seafoam stuff yet???

[fieropope]

worn pump gears maybe.when the oil starts to break down and get thin itll slid past the gears and not build pressure very well.

[AB'sLs1]

have you run that seafoam stuff yet???

whats seafoam?... never heard of it


i just wanna make the car safe for itself if u know what i mean

[seth_12]

Don't run 10w40 its way thick i tried it bc i thought the same thing but my valve seals were bad...they start to get worn out after 75k miles i would change them if thats the issure in your car or its gonna cost you a fortune to keep putting oil in it i had to put oil in mine every 4 days....pontiac recommends 5w30 but you can use 10w30 it depends on where you live, i live in Texas the weather gets really hot here so i use 10w30 but i switch to 5w30 around nov. till about march than switch back to 10w30

[pajeff02]

Seafoam is a chemical engine cleaner. It breaks up deposits in the motor and cleans the inner workings. Pros and cons to this type of system. AutoRx has been recommended as a gentler way of accomplishing the same thing, just over a period of time. In either case, you want to change your oil upon the recommended run time and not leave the stuff in your engine.

Rather than dump chemicals in your motor, maybe a little diagnostic work would be in order. A compression and cylinder leak down test will give you an idea of the condition of your rings and valves. Viewing your sparkplugs will also let you know what is going on in your engine. If you are seeing oil deposits on your plugs, have some blue smoke on startup, but have good test readings, it is likely that your valve seals have hardened and are not sealing as well.

As to the oil pressure, I would check it with a master pressure gauge, or even an aftermarket gauge just to ensure that you are getting accurate readings. I believe the '98s had oil pump issues, however, it only takes an afternoon to change out the pump should it be the issue. Fortunately, have not had to do it myself, but the procedure is pretty straightforward.

[AB'sLs1]

Seafoam is a chemical engine cleaner. It breaks up deposits in the motor and cleans the inner workings. Pros and cons to this type of system. AutoRx has been recommended as a gentler way of accomplishing the same thing, just over a period of time. In either case, you want to change your oil upon the recommended run time and not leave the stuff in your engine.

Rather than dump chemicals in your motor, maybe a little diagnostic work would be in order. A compression and cylinder leak down test will give you an idea of the condition of your rings and valves. Viewing your sparkplugs will also let you know what is going on in your engine. If you are seeing oil deposits on your plugs, have some blue smoke on startup, but have good test readings, it is likely that your valve seals have hardened and are not sealing as well.

As to the oil pressure, I would check it with a master pressure gauge, or even an aftermarket gauge just to ensure that you are getting accurate readings. I believe the '98s had oil pump issues, however, it only takes an afternoon to change out the pump should it be the issue. Fortunately, have not had to do it myself, but the procedure is pretty straightforward.

the plugs are fine a nice charmal color no deposites..... im not burning alot of oil just like a half quart between each oil change


im trying to move down to florida in the next few months and the car has got to take me there i wanna make sure the old girls got it in her yet .... i dont need it to stop pumping oil in like geogia or some where haha
so i wanna try to get this figured out... i dont think its to seirous but i wanna be sure

[pajeff02]

the plugs are fine a nice charmal color no deposites..... im not burning alot of oil just like a half quart between each oil change


im trying to move down to florida in the next few months and the car has got to take me there i wanna make sure the old girls got it in her yet .... i dont need it to stop pumping oil in like geogia or some where haha
so i wanna try to get this figured out... i dont think its to seirous but i wanna be sure

1/2 quart in 3,000 miles (I assume) is not bad at all. For an engine with your mileage I would actually say that is pretty normal. Any way you can confirm the oil pressure reading? I'm sure some other members will post up their thoughts.

[bamaz28]

Don't run 10w40 its way thick i tried it bc i thought the same thing but my valve seals were bad...they start to get worn out after 75k miles i would change them if thats the issure in your car or its gonna cost you a fortune to keep putting oil in it i had to put oil in mine every 4 days....pontiac recommends 5w30 but you can use 10w30 it depends on where you live, i live in Texas the weather gets really hot here so i use 10w30 but i switch to 5w30 around nov. till about march than switch back to 10w30

ran 10-40 in everything i have for the last 10 years or more no issues

[AB'sLs1]

what about highmilage oil.... would i get any benifit from that?

[shady milkman]

worn pump gears maybe.when the oil starts to break down and get thin itll slid past the gears and not build pressure very well.

im with fieropope on this one..change out your oil pump to be safe...but first seafoam

[0rion]

what about highmilage oil.... would i get any benifit from that?

maybe Sarge or Compsyn will chime in on this subject. I asked Sarge in the past but honestly don't remember what he said about it. The add packs are different and if memory serves me correctly he said it wasn't a hoax and do have positive properties for high mileage cars. Send Sarge a PM and ask him about it. Sarge knows his shit when it comes to oils.

[shady milkman]

i think the op is looking into the wrong area...burning a little oil (which almost all ls1s do..will not cause this) i would look into getting seafoamed..if nothing improves..IMMEDIATELY change your oil pump..its are cheap and should be changed anywho with high milage engines

[bigrondownhiller]

15-20 at idle is fine. If it drops to 10 then you should be worried.

[Hi-Po]

You really need to varify your oil pressure. Where is it at WOT? Sitting at idle, part throttle and WOT numbers would help. I dont know how your getting numbers of 39 and 41 out of the OEM gauges. To me, your OP sounds on the low side. If it 40 PSI at redline, its for sure on the low side.

[AB'sLs1]

You really need to varify your oil pressure. Where is it at WOT? Sitting at idle, part throttle and WOT numbers would help. I dont know how your getting numbers of 39 and 41 out of the OEM gauges. To me, your OP sounds on the low side. If it 40 PSI at redline, its for sure on the low side.

yea its at alittle past 40 at redline not quite to 60

[bamaz28]

you dont run a fram filter do ya?

[AB'sLs1]

you dont run a fram filter do ya?

no right now its purolator and before that mobil one

[Redphoenix1998]

Have you changed your oil and checked for metal deposits or sludge at the tip of the oil plug? Could be a worn O ring between the pickup tube and the oil pump. The times I experienced low oil pressure I blew my engine so be careful on this one. Sometimes changing the oil pump fixes it sometimes it doesn't. The pump is a gerotor type pump and really has nothing much to fail unless the gear clearance is waaay out of spec. Could be a plugged oil pressure sending unit. Check the oil for sludge and debris first to see if it can be chemically treated with seafoam or if it's a deeper matter and you have to tear the front end off to inspect the oil pump.