Low Oil Pressure at Idle
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If your oil pressure dropped more than 5psi and did not come back up after an oil change then you have a problem. Either a cam, rod or main bearing. You can fix it now with new bearings or you can fix it later after you do major damage. The drop in oil pressure is telling you that you have a problem somewhere and changing the oil isn't going to fix it. You should have had someone cut your old filter open. That would have told you what was going on inside you motor. You can hope and wish your problem away but it won't fix itself. Good luck with what you decide to do about it.
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Well I guess that is the only thing it can be.
After cleaning up the condensor last weekend, I started the engine. Temps got up to about 190-200*.
After checking for leaks, I checked my oil pressure again. The gauge showed zero!! I brought the rpms's up a bit, and the gauge started reading about 10#. Then I shut the engine off. But what is weird is I didn't hear anything out of the ordinary.
I am going to check the oil pressure sensor just in case. It sucks to think I have to pull this new engine.
After cleaning up the condensor last weekend, I started the engine. Temps got up to about 190-200*.
After checking for leaks, I checked my oil pressure again. The gauge showed zero!! I brought the rpms's up a bit, and the gauge started reading about 10#. Then I shut the engine off. But what is weird is I didn't hear anything out of the ordinary.
I am going to check the oil pressure sensor just in case. It sucks to think I have to pull this new engine.
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I had the same problem and it was the oil pressure sending unit. After putting that in I was at #50 at hot idle. The new sending unit wasnt a whole lot of money but I cant remember the exact amount.
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Don't wait until you hear noises. When you hear noises the repair bill goes up. Damaged crank, bent/broken rods... You might be able to get a way with just a crank polish and new bearings if you take care of it now. Or you could just need new cam bearings.
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Ed let us know if the new sending unit does any good. might as well replace the cheapest things first. if it fixes it great, but if not then you know what you have to do unfortunately.
hope everything turns out for the best. i just recently noticed my oil pressure dropped from 40PSI hot idle to 35PSI. i attributed it to the recent heat being 115 degree's. heat radiating from roads, hot engine, made since to me that it might have made the oil thinner, but who knows. i still get 65-70PSI cold start, but again who knows. i hope it isnt anything serious because i have a 1033 mile trip to make here in about 2.5 weeks!
hope everything turns out for the best. i just recently noticed my oil pressure dropped from 40PSI hot idle to 35PSI. i attributed it to the recent heat being 115 degree's. heat radiating from roads, hot engine, made since to me that it might have made the oil thinner, but who knows. i still get 65-70PSI cold start, but again who knows. i hope it isnt anything serious because i have a 1033 mile trip to make here in about 2.5 weeks!
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Originally Posted by SSkillz
I have the same problem im getting a new sending unit also hope it not a lot of $$
and not everyone stocks them...call around first~
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if youre going to buy a new sending unit for the stock guage...which is around 40 bucks.. why not spend a few $$ more and get a mech guage and really know what the pressure is.
my oil psi dropped from 35-40 hot to 25-30 hot after my head swap, and i know the oil needed to be changed before the swap anyway...and some coolant most likely seeped down when i pulled the heads off, so if changing my oil doesnt bring my psi back up, ill be going with a mech guage to really know the psi
my oil psi dropped from 35-40 hot to 25-30 hot after my head swap, and i know the oil needed to be changed before the swap anyway...and some coolant most likely seeped down when i pulled the heads off, so if changing my oil doesnt bring my psi back up, ill be going with a mech guage to really know the psi
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Originally Posted by 99FormulaM6
if youre going to buy a new sending unit for the stock guage...which is around 40 bucks.. why not spend a few $$ more and get a mech guage and really know what the pressure is.
my oil psi dropped from 35-40 hot to 25-30 hot after my head swap, and i know the oil needed to be changed before the swap anyway...and some coolant most likely seeped down when i pulled the heads off, so if changing my oil doesnt bring my psi back up, ill be going with a mech guage to really know the psi
my oil psi dropped from 35-40 hot to 25-30 hot after my head swap, and i know the oil needed to be changed before the swap anyway...and some coolant most likely seeped down when i pulled the heads off, so if changing my oil doesnt bring my psi back up, ill be going with a mech guage to really know the psi
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When you order your sending unit( got mine from NAPA) go ahead and get the thin wall socket made to put it in. All the sockets I tried had to thick of a wall. You can try all you want to but regular deep sockets will hit the valley cover in the back and it won't reach down far enought to get a grip on it. It isn't but about $10 and worth every penny.
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You might want to check your oil temperature. I am in the process of installing an oil cooler, NIGHTMARE. because my oil temp has been getting up to the 260-270* after some hard runs. Needless to say thin oil = lower oil pressure. Most people don't realize it but these bigger cube engines get hotter.
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I took it for a spin. Cruising pressure is 40#.
But at a hot idle. The gauge will show zero.
Car still idles fine. No weird noises.
Do they have a mechanical guage that will go where the stock sensor is?
But at a hot idle. The gauge will show zero.
Car still idles fine. No weird noises.
Do they have a mechanical guage that will go where the stock sensor is?