Oil leak / oil light

[mikey]

Oil leak(s) had gotten intolerable, and finally were actually leaving a little puddle, so I sprayed degreaser in the left side of the engine, where the crud was, and then hosed it down. I think I've stopped what was a minor leak from the front of the valve cover gasket, and once the engine was cleaned up, I saw a substantial leak immediately from the distributor. I always knew that it leaked, but it seemed to have gotten much worse: I could see oil running from it immediately.

While I was cleaning, I noticed a broken wire, and it turned out to be the one to the oil pressure switch, under the alternator. It might have been broken for months. Who knows? Once I had re-attached it, all seemed well until the engine heated up, and the oil light on the dash came on. When I disconnected the wire, the light went back off.

I just finished replacing the o-ring, and the distributor leak seems gone. I took the oil sensor out of the engine, cleaned it up, blew air into it, whatever, and put it back. Now, the light on the dash seems to stay off with the engine heated up.

By the way, the engine never overheated or such while the wire was disconnected. Is it at all possible that the leaky o-ring could turn that light on? What concerns should I have if the light returns?

[4wdchico]

Most of the electrical components in the T4wd are very high quality and last a long time. The oil pressure switch was not as long lived, leaking and coming out of calibration is somewhat common. So, if it were me, I'd replace yours with a new ND (Nippon Denso= OEM) unit. My guess it that Standard Motor Products part for the matter at hand is made by ND and is priced much lower than the same unit at the dealer.

[dlb]

if the leak at your dizzy was really bad, like gushing, maybe it could have caused it. but then that would mean that you could have been running with dangerously low OP for who knows how long. if that was really the case, you'd probably know it by now because the engine would likely be seizing up. so i would guess that the OP sender is marginal but you might pick up an oil pressure gauge and see where you're at, just to be safe. if you do check your OP, you will need a 1/8" x 28 BSPT male to 1/8" NPT female adapter for the gauge. toyota was pretty rigid about staying away from imperial stuff so they went with british standard pipe thread on this. took me a while to find this out but i was able to find the adapter pretty easily after i did. most auto hardware stores should have it.

when checking OP, let the engine warm up to running temp. the FSM says the lowest acceptable pressure is 4.3 psi but most gauges don't read that low, and if it is that low i think you have a problem. the rule of thumb that i've heard for OP is 10 psi per 1000 rpm.

[Petros]

I have a short somewhere in the wire harness and my oil light flickers on and off at randum. I installed an oil pressure gauge, completely removing the sender, just to keep from panicing everytime I saw the oil light go on. I have plenty of pressure, and the oil light still flickers on occationally, even though there is no sender at all. So either the wire has chaffed through somewhere or the light itself in the dash is shorted. Sooner or later I will get around to removin the annoying oil pressure bulb in the dash.

[mikey]

Thanks for the advice and reassurance. The light has mysteriously never come on again, so fingers crossed. There WAS a a lot of oil leaking, but not a gusher, so I really can't imagine it being the cause of the light coming on. Gotta hate coincidences, and gotta stop doing two repairs at once, which leads to misninterpreting.

Petros: Black tape is the easier solution.