Low oil pressure when the car is really warm

[Lcdxb]

Hello guys, I hope everyone is safe. I have a 2002 Landcruiser with 1fz-fe engine. I recently did an engine rebuild (six months ago) and I am not really sure now if they had changed the oil pump now. And I don't think they will remember now if at all they did. My problem is that my oil pressure seems to be in the middle on cold starts and rests at the second mark on normal runs. When I go offroad and the car is really warm, it even drops to almost zero or the first line. Any advice on how to proceed forward?

 

[Eicca]

Check it mechanically. Those pressure gauge senders are known to be less than accurate.

My old 3FE says basically zero oil pressure when fully warm. Been doing that for almost ten years now.

 

[AlpineAccess]

what oil weight?

 

[bigredmachine]

that's somewhat normal to see some pressure drop when the engine warms up as the oil is flowing more easily. I would check the pressure with a good mechanical gauge first and make sure that the crank bolt is torqued down correctly. the gauge on the dash isn't super accurate so I wouldn't be too panicked, make sure that theres oil in the truck and go from there

 

[Lcdxb]

Check it mechanically. Those pressure gauge senders are known to be less than accurate.

My old 3FE says basically zero oil pressure when fully warm. Been doing that for almost ten years now.

I will, just waiting to finish the corona madness

 

[Lcdxb]

what oil weight?

20w50

 

[Lcdxb]

that's somewhat normal to see some pressure drop when the engine warms up as the oil is flowing more easily. I would check the pressure with a good mechanical gauge first and make sure that the crank bolt is torqued down correctly. the gauge on the dash isn't super accurate so I wouldn't be too panicked, make sure that theres oil in the truck and go from there

crank bolt? How do I reach it? Can I reach it removing the valve cover?

 

[bigredmachine]

crank bolt? How do I reach it? Can I reach it removing the valve cover?

its on the front of the engine and its the bolt that holds the harmonic balancer in place. you will want a torque wrench as the spec is 304 ft/lb. if you search for low oil pressure in the 80 series section you will find more info as the 1fz was only offered in the 80 in the us

 

[Weezer]

your gauge showing low oil pressure at idle is normal. I’ve two 4.7s and they both show low pressure at idle. Different Toyota techs have all confirmed this over the years.....you’ll get use to it.

 

[HRTROB]

your gauge showing low oil pressure at idle is normal. I’ve two 4.7s and they both show low pressure at idle. Different Toyota techs have all confirmed this over the years.....you’ll get use to it.

No, it’s not normal. My 4.7 used to idle at the lowest mark. Replaced the sender, now oil pressure reads 1/4 at idle. The part is cheap and takes 20 minutes to replace so why won’t you fix yours?

 

[GorData]

I changed the sending unit on my LX470. Sometimes it would dip to zero. New unit and now it reads normal. My Nissan skyline uses the same unit and was doing the same thing.

 

[gungriffin]

No, it’s not normal. My 4.7 used to idle at the lowest mark. Replaced the sender, now oil pressure reads 1/4 at idle. The part is cheap and takes 20 minutes to replace so why won’t you fix yours?

From what I am reading, this is very hit or miss as to if it fixes the issue. You were one of the lucky ones. That said, the part is inexpensive and it doesn't seem to be much effort to try the fix.