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Hey folks,

I've been away a while, but now I return to ask your help.

Couple of nights ago, I was finishing my usual 25 mile trek home from work when I noticed that my Oil Gauge was sitting on the inside left dash. I was gonna sh** myself. I thought, "oh no, not like this!" I take a very lonely road home, and I was still 10 miles or so from home, so I didn't want to be stranded. Anyways, I stopped the car, and let her idle a bit to see if the needle would go up. It did, but came to rest pointing at the "O" in oil. I thought that if I got going it would pick up some more. It didn't. The needle this time moved over all the way to the left to the "L"!!!

Turned off the car once I got to a gas station (after driving very slowly). The needle didn't budge more than to the O ... no more.

I haven't driven her since, but I finally gots a day off tomorrow, so i want to take a good look.

A forum search tells me that I should check first the Oil Sending Unit.
1) Is this the same as an "Oil Pressure Switch" as sold by AutoZone?
2) Same search tells me that I will need to get a special tool to get this off; correct?
3) About how difficult of a task am I taking on?

Just did an Oil change about 500 miles ago. Goodyear/Gemini guys put in Shell Performance 10/30 and changed the filter. When I picked her up the mechanic told me that the oil pump was slow to get going, but ok once the car was running.
4) Could it be my pump?

My gauge has always been dumb, but I dont want to assume anything and then end up with a dead engine.

Finally, 5) Do you check the dipstick with the car warm or off?

thanks,

Jorge
 

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Jorge
Try the simple first. Check the oil with the engine cold.
If the oil is satisfactory ..meaning not low but within the marks of low and full.
If this is good check the wire connection to the oil sender.
If the wire is frayed or broken replace the bad section.
Then recheck the guage.
If the oil sender is leaking around the connection then it might be a good idea to replace it.
It does require a special socket ...lisle has one for it.
 

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Welcome back. OK, don't get too worked up just yet. You have an investment so do it right. It can be a bad sending unit/switch (same thing). However, you should test your oil pressure while you're at it. While you are out buying the special socket, get a rather cheap (low pressure type and not the high pressure type that is used for automatic transmissions) oil pressure guage. It should come with at least two different fittings to fit your engine. Remove the old oil sending unit and thread in your new oil pressure guage. Start your engine and let it idle till warm. Pressure should be between 5 psi and 30 psi. If so, remove the guage and install your new unit. If there is no pressure at all your engine should be making a lot of noise so some tear down will be required. Good luck.
 

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First thing to do is check oil level. If that is fine then you need to put on a mechanical oil pressure gauge to make sure yours is working correct. If oil pressure is still low it's time to pull the pan and start checking.
 

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Jorge. I don't know how many miles you have on your engine but both of my small blocks did the same thing just prior to rebuild. A friend of mine had a mechanical oil pressure gauge that we screwed into the extension that the sending unit attaches to. When the 351W started showing low oil pressure we hooked up the gauge and, sure enough, we only had about 10 lbs at warm idle. Rebuild time. When my 302 started doing the same thing I held out for either a bad voltage regulator on the dash or a weak spring in the oil pump bypass valve. I dropped the pan to change out the oil pump and came up with pieces of metal in the bottom of the pan. Those were my bearings and that was why my oil pressure was low.
 

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Never overlook the obvious...I had a recently installed oil filter fall right off my car one time...likely I noticed it before I drove it.
 
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