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Oil pressure sensor leak questions!

H8D-XJ

NAXJA Forum User
Location
San
I have a 90 XJ with the 4.0 and i developed a bad oil leak, i beleive its coming from my oil pressure sensor right above the filter. Is there just a gasket to replace or is it the entire sensor you replace?? And also ive heard oil can leak out by the distributor, is that a gasket as well. Id like to knock out all 3 while im there, the oil pressure sensor, dizzy and oil filter adapter just to be safe. Any help is much appreciated. Thanks!
 
Oil leak out the distributor is caused by a plugged crankcase ventilation system.

The oil pressure sensor is a fairly common source of oil leaks. Then a vehicle gets old, the o rings in the oil filter mounting housing can cause leaks as well. If I were tearing into the sensor, I would get a set of o rings from the dealer and hit both at the same time.
 
Oil leak out the distributor is caused by a plugged crankcase ventilation system.

The oil pressure sensor is a fairly common source of oil leaks. Then a vehicle gets old, the o rings in the oil filter mounting housing can cause leaks as well. If I were tearing into the sensor, I would get a set of o rings from the dealer and hit both at the same time.

Alright im positive its not out of the distributor i just figured i would replace a gasket if there was one as preventative maintenance. Its def coming from the oil pressure sensor, so my main question was to fix that is there a gasket or do i replace the sensor?? And ill def be doing the oil filter adapter o-rings just because im sure if i dont they will start leaking next week hahahaha
 
You might want to use some sealer on the threads of the sensor. Don't use teflon. If the sensor doesn't connect to ground through the threads, It won work.
 
They can either leak around the tapered pipe threads or out of the unit itself. I'd replace the unit and put sealer on the threads. If it's puking a lot of oil, it's probably the sender anyway. They usually don't just spring a leak from the threads.
 
Some (most?) oil pressure sending units come with a sealer already on the threads.
 
Yep... the new one I just threw in my '91 came with sealer on it already.

My gauge was acting EXTREMELY flaky, so I figured it was probably due for one, it fixed the problem.

The oil pressure sender is very commonly broken by inexperienced mechanics while doing an oil change since it's right next to the filter, so I wouldn't be surprised if your leak is coming from the sender itself. I've seen some pretty horrendous ghetto fixes (involving large quantities of RTV and tape) applied to avoid replacing the sensor the right way, too.
 
Alright it actually looks like where the sensor screws in isn't leaking. It's the bolt or fitting that the sensor screws into that looks like it's screwed into the block that's leaking. What the hell is that piece called? At this point I'm not exactly sure what's creating this crazy leak it seems to leak mostly while driving not really at idle. Will make a decent puddle when I stop and park after driving it for a bit.

My valve cover gasket does seem to be seeping so I'm going to fix that. My list to fix on Tuesday is oil filter adapter o-ring, oil pressure sending unit, the bolt or fitting that the oil pressure sending unit screws into and valve cover gasket. If that doesn't fix it then I'm lost.
 
This is really strange because about 4 days earlier the car was leaking absolutely no oil on the ground and in one trip to work i all of a sudden have this pool underneath my car. I see some weeping from what looks like the headgasket but i dont think thats my issue.
 
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