I just picked up a really nice 1992 4runner and it runs and drives fine the only thing is the oil psi will go from hi to low and back to hi and it is just all over the place. I guess what I am saying is I am new to toyota's and I was wondering if the sending unit is a good place to start. It has the V6 engine in it. Any help would be great

 

Typical normal. Checked the dipstick?

:wabbit2:

 

Yes that was the first thing I did

 

They all do that. As long as you have the right amount of oil in there I wouldn't worry about it.

 

yes i have to agree. Mine does the same and i too was worried at first. But then i realized, Ive had a mazda that did that, a ford that did that, a blazer that did that and a few others too

 

Yup normal. The more mileage on the engine the more fluctuation you will see. Plus the OEM senders aren't the most accurate thing in the world either. Mine jumps from just below 1/4 at times at idle and hot to about 1/2 way when driving. And this is on a rebuilt engine with about 15 K or so on it. But of course it's also a 22r not e 3.0. But they all do the same thing for the most part. Unless it's running at 1/4 when hot and driving then you have nothing to worry about.

 

thanks that makes me feel better about driving it.

 

mine did that and started knocking although the engine had a fire before i got it

 

Begging the question, what is a best way to monitor pressure? Mechanical gauge or electrical sending unit?

We all know the idiot lights are SCARY!

 

u cant beat the mechanical guage.....

My $0.02.... if the guage goes all the way to high, I would be concerned... That could be due to sludge build up in the motor, not allowing oil to flow properly.... Not sayin this IS your problem, just something u might wanna check out with a mechanical guage.... Too much oil pressure, is just as bad, if not worse than too little....

 

good catch team420. I guess HI unless using 3/4 to full is a relative term all of us had missed.

 

I'm guessing this has more to do with a SHORT in the wiring to the oil pressure sending unit than it does fluctuations in the oil pressure. That was my problem. Soldered it back in place & no problems.

 

Most likely true.... But, better safe than sorry, I have seen numerous engines seize with super high oil pressure, due to sludge, or clogged oil passages for some reason or another.... Get the mechanical guage on it, and go from there....

 

If you really want to clean out a motor, run Red Line 5W-30 for 5-6k miles, and use a couple Purolator PureONE PL20195 filters. Change the filter at 2k miles (and top off oil since you'll lose some in the filter).

Red Line oil is a Group V synthetic ester, which removes sludge like nothing else. Esters are highly polarized long chain molecules, which attach to dirt just like detergents.
http://www.summitracing.com/parts/RED-15304/

The PureONE filter is probably the best filter available for our motors - filters smaller particles and has great flow. Advance Auto carries them, or you can get them from amazon.
http://www.amazon.com/Purolator-PL20...dp/B000E8T83S/

x2 on cleaning up the sender connector.

 

Thanks for all the info I am going to put a mechanical guage on it and see how it looks.