Low Oil Pressure issues

[Tonupboy]

New member here...been lurker for a while, but noticed some great answers so I registered and be contributor...

Anyway, I have 1993 Rodeo 4WD V6 with 125,000 miles. Yesterday, I noticed that my oil pressue drops to zero during a warm idle at the stop light. As soon as I hit the throttle it goes up again. In addition, I don't hear any pings or knock (even in idle). So I pull over and check the oil level. Looks fine to me, no leaks either. The oil gauge registers a solid red when Im at idle (warm engine), not blinking. When this happens, I dont notice any drop in revs, its actually normal....Should I worry and get this fixed right away or can I live with this for a while? (Mechanic funds are low at the moment....) Thanks, fellas...

[Slade901]

Check your oil sensor and try to clean it if is covered with hardened oil crud. When was the last time you have an oil change months and mileage?

[amigo-2k]

Your oil pick on the oil pump (I think that is what is connected too) could be dirty and full of sludge.

Solution:

Get the truck good and hot and then drain the oil.

or

pour in a half can of sea Foam and then drive it for 30 minutes and then change the oil. I worry about having 125k and using sea foam may dislodge a bunch of crap and clog something else. If you have used oil/gas additives in the past you should be fine to use sea foam.

-Ryan

[Tonupboy]

Originally Posted by Slade901

Check your oil sensor and try to clean it if is covered with hardened oil crud. When was the last time you have an oil change months and mileage?

I have no idea when he (Dad) changed the oil, but it still looks fine when I checked (not blackened or cruddy). On the 93, where is the oil sensor located? Is it near the filter? Is that the same as an oil pressure switch?

[Tonupboy]

Originally Posted by amigo-2k

Your oil pick on the oil pump (I think that is what is connected too) could be dirty and full of sludge.

Solution:

Get the truck good and hot and then drain the oil.

or

pour in a half can of sea Foam and then drive it for 30 minutes and then change the oil. I worry about having 125k and using sea foam may dislodge a bunch of crap and clog something else. If you have used oil/gas additives in the past you should be fine to use sea foam.

-Ryan

A local mechanic wanted me to change the oil pressure switch for $150 (the part alone, he said was a special order at $120.00). To me, that's a lot of cash for an old truck. I have used gas additive such as STP fuel injector cleaner and Lucas additives, but not oil additives. I will try the sea foam route and oil/filter change first before spending that much. Is Sea Foam a strong engine flush? I heard those who used Gunk Oil Flush is so strong that it clogged up engines and pumps....

[Slade901]

Originally Posted by Tonupboy

Is that the same as an oil pressure switch?

Oil sensor is the same as the Oil Pressure Switch.

[rodeo02]

Originally Posted by Slade901

Oil sensor is the same as the Oil Pressure Switch.

Some have a sending unit for the oil press gauge and a 'pressure switch' for the low oil press warning light. Low warm idle oil pressure is fairly common on HIGH mileage 3.2's. Like Ryan says, your screen on the oil pump pickup screen is either plugged with debris, or the screen has sucked itself up against the p/up tube (fairly common on this engine). With that small amount of screen to work with, It plugs easily. You will need to pull the small lower stamped steel oil pan to inpect the screen. Not too bad of a job.
G/luck!
Joel

[Tonupboy]

Originally Posted by rodeo02

Some have a sending unit for the oil press gauge and a 'pressure switch' for the low oil press warning light. Low warm idle oil pressure is fairly common on HIGH mileage 3.2's. Like Ryan says, your screen on the oil pump pickup screen is either plugged with debris, or the screen has sucked itself up against the p/up tube (fairly common on this engine). With that small amount of screen to work with, It plugs easily. You will need to pull the small lower stamped steel oil pan to inpect the screen. Not too bad of a job.
G/luck!
Joel

Yeah, I'm gonna go for the obvious first like adding Sea Foam in the engine and changing oil and filter...if it comes back, the pan goes off and inspect the screen....now, do I just clean the screen with something and put it back...or is it a more complex step to it?

BTW, you guys rock! Thanks for the tips so far!

[Ramblin Fever]

FWIW these 3.2L V6 engines LOVE clean/fresh oil, and enjoy every 3K mile oil changes. In fact, I don't recommend going over 3K miles per oil change.

I've always done 3-3,500 miles ritual, original owner, however, for the last 6 months, my oil pressure at idle was down to 10psi. They say that's normal after it's warmed up, as long as pressure goes back up upon acceleration - usually 40-60.

However, there for about 3-4 oil changes, I only clocked 1-2K miles before changing out oil/filter; and this time around, I've noticed oil pressure has increased dramatically at idle, instead of the 10psi, it stays at close to 45-50 or so. And accerating psi is close to 75-80.

I didn't add anything at all to the oil, just got the truck good and hot before draining oil. I don't think I'll ever go as long as 3,500 miles again before changing, it seems to like it at every 2,500-3K at most.

Don't know why, but I'm leary of running any kind of oil additive, personally.

[Tonupboy]

I added Lucas Oil additive today (local Strauss Auto didnt carry Sea Foam). I heard this is awesome. I'm going to wait until Saturday to get that oil changed and see what happens then. The oil is fairly new so I'm not sure exactly what is going on. It might as well be the oil pressure switch found near the oil filter that is causing the low pressure readings...we'll see.

[amigo-2k]

Lucus is an oil stabilizer, it is not going to clean out carbon and gunk out of your engine. Walmart has some products like sea foam.

[Tonupboy]

Originally Posted by amigo-2k

Lucus is an oil stabilizer, it is not going to clean out carbon and gunk out of your engine. Walmart has some products like sea foam.

I got it...they were also selling some engine flush but I was leery about those. I guess I will try Walmart today and see if they have Sea Foam. Is it easy to swap out the oil pressure switch (someone told me its located near the oil filter with wires sticking out)? If so, has anyone done this without asking the mechanic?

[amigo-2k]

http://www.themotorbookstore.com/rodeo.html

hook up with a manual ....