Low oil pressure.

[get me on the road]

Well I'll wait a couple days and see if Chevytech reads this, maybe he'll know a test I can perform. I would just r&r the sender but the parts store wants $65 for a new one. I may pop the instrument cluster out and leave it out for a few and see what happens, but its running at 15 now, so I dont know. Thanks for the input guys.

[piecesparts]

Originally Posted by get me on the road

Well I'll wait a couple days and see if Chevytech reads this, maybe he'll know a test I can perform. I would just r&r the sender but the parts store wants $65 for a new one. I may pop the instrument cluster out and leave it out for a few and see what happens, but its running at 15 now, so I dont know. Thanks for the input guys.

I think your parts guy is off just a little bit on price. A pressure sending unit for my truck is $29.45 at the local NAPA (just checked) and that is about what I have paid in the past. I am not sure what the part he looked up, but it sounds high.

As for troubleshooting oil pressure issues, I would try the el cheapo oil pressure gauge trick, connected to the same port as the oil pressure sending unit is screwed into and see if you really have low oil pressure. You won't have to drive with this, just start up the motor.

[get me on the road]

Well I told the parts guy to look up an oil pressure sending unit. That is right, right? If my dash just had a light the unit would be $8, but if the dash has a gauge, which mine does, then it would be $65. There is a NAPA in the next town over, so I'll call Monday and see what they want for it.

[piecesparts]

Originally Posted by get me on the road

Well I told the parts guy to look up an oil pressure sending unit. That is right, right? If my dash just had a light the unit would be $8, but if the dash has a gauge, which mine does, then it would be $65. There is a NAPA in the next town over, so I'll call Monday and see what they want for it.

My truck has a pressure gauge and the price was as I said $29.45 and in stock as of today. Take a look at your plug for the sending unit, some are three prong and others are two prong plugs. Mine is a three prong sending unit and wire plug.
This sending unit is at the back of the motor by the firewall, just behind the distributor.

[get me on the road]

I went out and looked pieces, my sender has a 2 wire plug, and the sender is sticking out of a 90 degree (looks like brass) elbow. So if I want to take that elbow out and clean it which I do, I may have to remove the intake. Which would give me one of those cheap/sorta long jobs to do, and I am all for that.

[ChevyTech]

Well I'll wait a couple days and see if Chevytech reads this, maybe he'll know a test I can perform.

Unplug the connector from the oil pressure sending unit.
Turn the key to the on position.
The oil gauge should go all the way high.

If it did go high you can either put a mechanical test gauge on it to read the pressure or replace the oil pressure sender.

When the oil pressure is very high, the oil sending unit has approximately 90 ohms resistance.

I went out and looked pieces, my sender has a 2 wire plug, and the sender is sticking out of a 90 degree (looks like brass) elbow. So if I want to take that elbow out and clean it which I do, I may have to remove the intake. Which would give me one of those cheap/sorta long jobs to do, and I am all for that

Be careful. It is very easy to break off that brass elbow. Unscew the sender from the elbow but you may want to support the elbow so you do not exert any force on the lower end of the elbow. Then you can unscrew the elbow if you want to take it out. No need to pull the intake manifold.

I will say it one more time. It is VERY easy to break off that brass elbow.

[piecesparts]

Originally Posted by ChevyTech

Unplug the connector from the oil pressure sending unit.
Turn the key to the on position.
The oil gauge should go all the way high.

If it did go high you can either put a mechanical test gauge on it to read the pressure or replace the oil pressure sender.

When the oil pressure is very high, the oil sending unit has approximately 90 ohms resistance.

Be careful. It is very easy to break off that brass elbow. Unscew the sender from the elbow but you may want to support the elbow so you do not exert any force on the lower end of the elbow. Then you can unscrew the elbow if you want to take it out. No need to pull the intake manifold.

I will say it one more time. It is VERY easy to break off that brass elbow.

The oil pressure connection "Tree" on my 91 truck is not brass, but I agree with Chevytech, these fittings can be broken easily. On my 84 and my son's 86 they are brass, and sit down in the corner of the intake manifold. In all essence, I believe that taking it off may not be the best of ideas. Changing the sending unit is not a bad thing, but leave the connection point alone.

[get me on the road]

DUT DA DA DAAAAAAA......... ChevyTech to the rescue, thanks for the reply. I will check that tonight. As for the sender, theres no way to test it with the engine off? I dont think it will start or run with the sender unplugged, but then again I dont know. Does it read lbs of vacuum or pressure, so could I take the sender off and hook my mighty vac to it or put my air nozzle from the compressor to it and put a little air pressure to it? Can I safely clean the sender?