4.7L oil pressure issue

Agreed. @usedpartsprince, do you think you are not getting oil pressure based on your cluster oil pressure gauge?

 

Mine shows halfway on the gauge most of the time when driving. Only drops to 1/4 at idle, when fully warmed up. Cold acceleration its 3/4s to the top.

 

My guess @OP is that maybe their gauge may not be the correct pressure range but maybe I'm nuts. It's only ~4psi at idle.

And both the levels and gauges are different from early to later years. This topic came up a couple of times in the past.

Most recently here: https://www.tundras.com/threads/oil-pressure.128909/

And here for more info on how many psi to expect and showing examples of how different : https://www.tundras.com/threads/low-oil-pressure.103485/

There's another thread around here that speaks more to the years and gauge changes, but earlier models typically hold a low level on the gauge. Doesn't mean anything is wrong. Check the FSM page at that 2nd link for details on how to test and what to expect.

 

Here is idle vs 3500rpm in my '04 w/ synthetic 5w30 oil.

 

Money light is on.

 

Small evap leak. I need to smoke test the filler neck.

 

We've probably already talked about this, but I'm forgetting. Did you confirm if your VIN is impacted by the filler neck cracking problem from the TSB? (link)

 

My VIN is higher than the one you listed so I'm thinking mine isn't affected.

 

After all of what I did, still no pressure to the gauge.

So, I did an oil change with new filter, and when driving the gauge needle comes up above the first mark and drops to nothing when idle.
Now I'm wondering if it's an oil pump issue?
Although it runs great and no ticking like lack of oil.

 

Mine is similar, but idle I have nothing.

 

This is what I tried doing to check oil pressure with a mechanical gauge. I didn't get oil to the gauge as it should've.

Now I just did an oil change and it's moving the needle when driving, but nothing at idle.
Also I ran a can of BG's EPR to help remove anything in the engine that may have been slowing down the oil flow. The oil coming out was black and only 1000 miles since last oil change.

I plan on doing that again at 1000 miles and then using a mechanical at the filter.

 

Lack of noise is the only reason I'm not thinking anything is clogged. If you had oil attrition, I'd expect extra chatter. It's not exclusive but I think it's a telling sign, no noise is good news.

Generally speaking, a lot of (if not most?) modern engines use a pickup tube system. My favorite, the GenIII GM small blocks, and your V8 2UZ-FE are no different.

If you are really, truly concerned there is no oil uptake happening, I guess the first thing I'd do is proactively get whatever gaskets were needed to pop the oil pan off, so you can get access to look at and potentially clear the oil pickup tube. The pickup tube usually has some form of screen in it. That screen can - theoretically - get clogged up. Here's what I mean, here's a picture of a 2UZ-FE / 4.7L V8 from the underside, with the oil pan off, and the bottom-end exposed. Clearly shows the pickup tube that sumps oil out of the pan. Maybe you have a slew of sludge down there, or, say, someone had something plastic get broken up and it's clogging the screen? This isn't to discount any number of other ports and crap that could get clogged in the block and heads. But ... this is the one you can easily get to and check. Note from the pickup, with the screen that could potentially be clogged, the pip then routes off at 7 o'clock, to pump oil up into the top-end. And actually, now that I look at it, I'm not 100% sure you can get to the pickup just by removing the oil pan. Let me find an exploded diagram. (EDIT : Indeed, I don't think you can, see my next reply)

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Yeah, looks like you may not had access to the pickup tube just by removing "oil pain #2"

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Thanks for this info...

 

Thanks for that info also!

 

In an ongoing quest to see good oil pressure, after one oil change with a quality oil and quality filter, the gauge does work. However, after driving a while the pressure drops and at idle it shows nothing. This photo added is 1st start, 6:00am, 56 degrees outside.

I'm starting to wonder if this engine has an oil pump issue? Or if the engine just doesn't put out due to age?

I have seen oil pumps and bearings slowly wearing out on american V8s showing that cause low oil pressure.

 

Unless it’s early brain wise, the bottom gauge showing nothing is your coolant temp. The one above it is your Oil gauge, which has what I view as normal reading at idle.

IMHO you have a ECT(engine coolant temp) senor circuit issue.

For 2000....
W 3(grey connector) Water Temp. Sender....for idiot gauge
E 2(green connector) Engine Coolant Temp. Sensor....input to ECM



Disregard light green circle courtesy of @Tundra2

 

I believe he is following up trying to show that the oil pressure gauge is working after a cold start but then stated that after warmup it drops to nothing at idle.

 

Perhaps but at idle @900 RPM means engine is warm, he has nothing for water temp….not normal, simply another issue to address.

 

That's at a cold start with 56 degrees ambient temp.

 

Yes I am aware of that but with that temp, engine RPM would be muchhh higher, not a idle RPM reading.
Perhaps @usedpartsprince can clarify and despense with speculation

 

a couple thoughts of my own...

-i wouldn’t trust a oil pressure gauge with a mechanical sender in any vehicle. The pressure lines are very well know to fatigue and rupture. When they do it’s a HUGE mess. And that huge mess means you’re loosing oil fast. An electrical sending unit is waaaay more safe.

-i don’t think having air inside the oil pressure sending line is that big of a deal. Yes, it would be in a hydraulic brake lines where it’s around 1500 psi, but if you’re engine has around 60psi, i wouldn’t think it would sway the results very much. At least it didn’t when i had a mechanical gauge in my old ford. Drive the truck around for a while and the air will work its way out of the line.

-your tundra’s oil pressure gauge reading look normal to me. It’s the exact same as mine, and it sounds like it’s the exact same as others.

-a simple fix for your Henny Penny sky is falling concern would be to remove the gauge cluster, remove the stock oil pressure gauge from the back, carefully pry the needle off its post, then reposition it an additional 1/4 of the way up further on the post...

 

I'm a gear head for many years now by the way, this is at first startup, no temp reading at that point.
Just not sure what would keep oil pressure from reading better all the time?

Oil pressure is better after an oil change, and seems to run well.
I'm not liking the gauge not showing better pressure all the time.

 

I don't find it confidence inspiring either. I can only assume that that's how our Tundra oil pressure gauges are from the factory? Or perhaps the gauge just wears out over time? If the concern is there, maybe just do a preliminary oil pressure test with a brand name high quality oil pressure gauge. Compare that reading to the OEM gauge and make a mental note of where it's at on the oil pressure scale. I guess there's nothing wrong with the ubiquitous 2-1/16" triple gauge mount that gets screwed under the dash.

 

I'm not sure if you're mostly concerned with low oil pressure, or if you just desire an accurate reading... but, if you want to skip some of the headache, Summit has a high-volume Melling pump for 120 beans. I know it's standard-pressure, but at least you will have the peace of mind knowing it's a fresh unit, and it will flow more volume than OEM. See what the gauges read after the fresh pump
[EDIT] I forgot what year your truck was. This was a search result for my '02



https://www.summitracing.com/parts/mel-m371/make/toyota/model/tundra/year/2002

 

If you're not a bot say potato.

 

Has anyone changed the oil pressure sensor & gotten a better reading?

 

Before I learned about the low reading being normal I almost changed mine out. I didn't do it, but somewhere I ran across a thread/post/write up with an "explanation". "The inlet in the original pressure sensor is too small and plugs up" I looked at and compared dozens of replacement units online and there IS a difference in the size of the inlet hole. Anyone else run into that info?

 

Mine has run just at or below 1/4 at idle since I bought it. It’ll get up around 1/2-5/8 under acceleration. Hasn’t changed in 168k miles

 

There is a TSB regarding sensor replacement on some vehicles because of issues with oil sender units. I saw Bubba posted about it on here, IIRC. Could be related.