1992 Nissan Pathfinder, VG30E Engine

A month ago I drained the oil/removed the filter to pull a defective starter. I fixed that and a couple of days ago replaced the old oil, put on the old filter, and started it up. No problem with the oil system as I worked on a Poor Performance issue, which still remains. BUT, as I was troubleshooting the ignition system, I noticed the Oil light was on. I immediately s/d the engine and checked level: OK. Then I drained it; nothing significant was in the oil. But there was some light debris, like particles of wings, from bugs in it.
I pulled the filter: no noticeable debris in it or in the port on the Block.
I pulled the oil light sender.
I’m thinking I have a clogged system, so I blow air thru the filter and oil light sender ports, dump some gas into the oil fill port, letting it drain thru the still-open sump drain. Then I over-fill it with diesel fuel, spin the engine a bit (with the ign disabled), and get fuel squirting out the open filter port. Drain diesel fuel.
Now I’m thinking that whatever it was is flushed out, but I didn’t get anything significant out via either the gasoline or the diesel fuel.
Fill it back up with fresh oil (this time) and a new filter (this time), put just the connection tube from a stand-alone pressure gauge into the sender port, and start it: no oil coming out the sender port after about 45 seconds of running at fast idle. S/D.
Remove tube, blow air into the port.
Start again: no oil coming out of the open port after 20 seconds. S/D.
NOTE: I hear no noticeable change in engine noise thru all of this.
Pull filter: dry inside. No oil ever reached it since it and the new oil was installed.
I had the sump about 1/2 QT high, so I drained about a quart (in case it was air-bound due to the frothing) and just spun the engine a few times: no oil coming out of open ports.
SO, MY QUESTION: What is your opinion on my situation with the engine? And what do you suggest I do?

1 thought on “1992 Nissan Pathfinder, VG30E Engine”

  1. I think to begin with that the oil pressure sending unit was bad as this is quite common. If you had replace the sending unit and changed the oil and filter it would have been fine. (of course putting some oil in the filter before installing it would have been a good idea, but I have changed plenty of oil filters without doing so with no issues)

    That said, to the issue at hand. Putting diesel fuel in the engine would make it work like a degreaser and would loosen large chunks and clog the oil pick up tube. No oil in the filter, the pick up tube is clogged. Now you are looking at taking off the oil pan and unclogging the pick up. There will be no pressure until the oil pump can pick up oil.

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