03 with oil pressure issues when hot

[MikeinNH67]

I could have sworn I already posted this but I can't find it anywhere and my ID says none created by me so I'll try again...at least I saved the info.

I'm new to this forum and to Toyotas in general except for brake work on Camrys. So I picked up an 03 Limited with the V6 for what I thought was a decent price. Now that I'm into it that price was not so great, this thing was ignored a lot. Here's the scoop, I got it fixed up mechanically (brakes, brake lines etc) then after a few months of tinkering I finally get it registered only to find the oil pressure light would flicker after it was warmed up. I did a ton of googling and found these things sludge up if ignored. First thing I did after installing a mechanical gauge was pull the small oil pan and oil pickup, it was caked with crud. Put it back together and oil pressure was much higher but would still drop down to nothing or almost nothing when at normal engine temp after driving a bit. Shut the engine off for 15 seconds and it would be back up then drop again after a 30 seconds or so. I then pulled the intake and valve covers, the passenger side wasn't too bad but the driver's side was pretty gunky especially near the chain. I scraped and vacuumed both sides, none of the return ports looked clogged. Of course the PCV valve was stuck open so that and valve cover gaskets were replaced. Really no change after that. So now I'm wondering if the oil pump has issues but why would the pressure pick right up after shutting off for a small amount of time? It almost seems like the oil isn't getting back to the pan quick enough but if I shut it off when the pressure drops and run over to the dipstick the level looks normal.

Extra to add since my initial write-up. Reading I found that a quart of ATF can free things up so I now have some in there and am running it for a bit each day. It seems to be getting better and holding better too. I'm thinking maybe the relief valve in the pump housing is/was sticking open.

So this is where I'm at, suggestions and thoughts would be appreciated.

Merry Christmas! :cheers:

 

[Brian3676]

If your oil galleys, pan and pickup are all clean, and assuming your not low on oil, then low pressure at operating temp is typically a sign of worn bearings/jurnals/oil pump. All that sludge could have caused wear on the engine and now its too late. You running something like a 5-30?

 

[MikeinNH67]

If your oil galleys, pan and pickup are all clean, and assuming your not low on oil, then low pressure at operating temp is typically a sign of worn bearings/jurnals/oil pump. All that sludge could have caused wear on the engine and now its too late. You running something like a 5-30?

I'm running what is listed on the cap, I think it's 5w-30. I hope it's not internal wear and it seems a bit intermittent for that. If it is wear then I may just part this thing out. I'll probably move up to a bottle of engine flush next. Thanks for the reply.

 

[Brian3676]

Try using a qt of ATF before using the engine flush stuff, the engine flush is like a solvent and its mixed reviews weather it help or just causes more issues. Put the ATF in a few hundred miles before changing the oil.

Also try an OEM toyota filter. I have seen the aftermarket ones cause oil pressure issues. Never on a 4Runner, but it's worth a shot.

 

[MikeinNH67]

Yeah, kinda what I'm thinking. The flush will be last ditch effort I guess. The oil/filter has been changed since I noticed the issue. I do have a couple new Denso filters I recently got from RA, no actual Toyota filters. Thanks!

 

[Falcon3]

Before the ATF, try some Short oil change intervals with some high detergent oils might help. Like 500 miles per, and try to get the oil up to temp and do longer drives. To keep cost down, use a good semi-syn like Maxlife in 5w-30. I’m concerned the atf will knock loose too much gunk and clog it more, or clog the filter. There’s a thread on BobIsTheOilGuy about a guy with a project 1gr-fe with oil and timing chain issues, he might have some insight on your problem.

 

[MikeinNH67]

Thanks Falcon, the ATF is already in there and I really couldn't drive it more than 15 mins without the pressure dropping to the floor. So far it seems better. I'll do some reading on Bobtheoilguy.

 

[MikeinNH67]

So I'm driving it every couple days at night (no inspection sticker yet) and it does seem to be getting better. I'll keep doing this for a bit. Since I put new plugs in the thing runs great, just gotta deal with this issue.

Curious, for those who have a oil pressure gauge, what is the normal pressure when up to temp?

thanks,

 

[AuSeeker]

So I'm driving it every couple days at night (no inspection sticker yet) and it does seem to be getting better. I'll keep doing this for a bit. Since I put new plugs in the thing runs great, just gotta deal with this issue.

Curious, for those who have a oil pressure gauge, what is the normal pressure when up to temp?

thanks,

I don't have a gauge, but as a mechanic, typical oil pressure ranges from a low of 20 to 30 psi at idle up to sometimes 60 psi on some engines at higher RPMs, but average range for most stock engines is between 20 to 45 psi.

 

[Brian3676]

I don't have a gauge, but as a mechanic, typical oil pressure ranges from a low of 20 to 30 psi at idle up to sometimes 60 psi on some engines at higher RPMs, but average range for most stock engines is between 20 to 45 psi.

This is what I find also. The general rule of thumb is 10psi per 1k rpms at the minimum. Each engine will have it's own specs that vary, but that's the general rule of thumb.

On imports I see 15-20 psi at idle typically. If you check a FSM it will have specs in it

 

[MikeinNH67]

Thank you.

 

[MikeinNH67]

Oil pressure issue - resolved

Just to close this out, I ended up running Motor Medic's Engine Flush as directed in the instructions. Then did another oil/filter change and cleaned out the oil pan/strainer at the same time. Man there was lots of crud in the pan after that. With all I've done the pressure now stays between 14 and 20 PSI at idle when up to temp. It also rises normally when the RPMs rise. Lastly, the oil looks much cleaner after running for a few weeks, it would turn black quickly before. I'm calling this one a success. I will pull the pan again in the near future to make sure there's no more debris but this truck is now able to be my daily driver.

:lookout: :tea:

 

[MikeinNH67]

Just wanted to update this a few years after the original fix. This past spring (2023) I noticed the pressure on my aftermarket gauge acting a bit weird then one day I had a similar issue again. This time though, pressure would drop off at idle if revved too high even when cold. Seemed like the pressure relief valve was sticking open like I think it did in 2021. After a few restarts I was able to limp it home with enough pressure as long as I kept the RPM's down. I did the Motor Medic flush again and pulled the oil pan to inspect the pump. The pickup mesh was full of crud again but not like the first time. I then cleaned it and did the oil/filter change. Haven't seen the issue again. We'll see if it comes back in the future. I'm sure in the past this engine went way too long between oil changes but I do the proper oil maintenance and it gets at least a synthetic blend.

 

[daprotege5]

Just wanted to update this a few years after the original fix. This past spring (2023) I noticed the pressure on my aftermarket gauge acting a bit weird then one day I had a similar issue again. This time though, pressure would drop off at idle if revved too high even when cold. Seemed like the pressure relief valve was sticking open like I think it did in 2021. After a few restarts I was able to limp it home with enough pressure as long as I kept the RPM's down. I did the Motor Medic flush again and pulled the oil pan to inspect the pump. The pickup mesh was full of crud again but not like the first time. I then cleaned it and did the oil/filter change. Haven't seen the issue again. We'll see if it comes back in the future. I'm sure in the past this engine went way too long between oil changes but I do the proper oil maintenance and it gets at least a synthetic blend.

my current short block has about 15k miles on it, my serpentine had shredded and wrapped around the main pulley which caused the front crank seal to break into pieces. replaced all of that, changed oil and thought nothing of it since i had no oil leaks after changing the seals and belt. even took it to tennessee, on a most recent trip with the trailer attached my oil light flashed, which gave me the WTF its a new motor. took the oil pan down and low and behold bits of the serpentine and the crank seal pieces melted together and were blocking the screen. so cleaned it and thankfully everything has been fine since than. except stupid exhaust leak again.... lol

 

[MikeinNH67]

my current short block has about 15k miles on it, my serpentine had shredded and wrapped around the main pulley which caused the front crank seal to break into pieces. replaced all of that, changed oil and thought nothing of it since i had no oil leaks after changing the seals and belt. even took it to tennessee, on a most recent trip with the trailer attached my oil light flashed, which gave me the WTF its a new motor. took the oil pan down and low and behold bits of the serpentine and the crank seal pieces melted together and were blocking the screen. so cleaned it and thankfully everything has been fine since than. except stupid exhaust leak again.... lol

Been there with the serpentine belt, not fun and that could have been some of what I cleaned out in the spring but I don't recall any stringy bits. These motors seem to take quite a bit of abuse though and keep on going. Exhaust leaks always stink. Good to hear you're oil issue is over. Makes me think I should change the belt just because it's over a year old.