how to tell between the two
how to tell between the two alright well i replaced my oil sending unit, and that didnt fix my oil pressure problem, and my mechanic said that its either the oil pump or a main bearing... is there any way to be able to tell between the two of which one is going out?
more info please. describe the problem. you have low oil pressure? when? whats the situation on the car, mileage, is it running? are you putting a new motor together and you ran into this problem? elaborate please.
Yes! Is it making any strange noises? When it's warm or cold? Have you tried a different oil filter?
(stupid question...Does it have 5 quarts of oil in it? Are you positive??)
lol my bad, just wanted to keep it short and sweet... but here we go
alright, well the motor is the stock motor that has been in the car forever... 150k miles... basically no mods besides cold air and exhaust... i cant hear any strange noises at any time, but it seems that the pressure is good from a cold start, but as the car warms up the pressure drops to almost nothing... i replaced the oil pressure sensor, but that didnt fix my problem... and ya im positive its got oil and the filter is good on it... i think its a fram filter, and the oil was changed about 1k ago... but it just seems as the car warms up the pressure just keeps dropping...
alright, well the motor is the stock motor that has been in the car forever... 150k miles... basically no mods besides cold air and exhaust... i cant hear any strange noises at any time, but it seems that the pressure is good from a cold start, but as the car warms up the pressure drops to almost nothing... i replaced the oil pressure sensor, but that didnt fix my problem... and ya im positive its got oil and the filter is good on it... i think its a fram filter, and the oil was changed about 1k ago... but it just seems as the car warms up the pressure just keeps dropping...
You should hook up a mechanical gauge to verify the low oil pressure first and foremost. There could be a wiring problem somewhere causing a faulty reading. If it validates the pressure seen by the sending unit then it is something mechanical.
Without knock being present then a rod bearing would be hard to say, as well as any bearing for that matter. The thing is these have very tight clearances as is and most likely damage is already done no matter what caused the condition. I have seen a clogged oil cooler do the same, as well as a lost pick up off the pump, bad pump and of course rod bearings, never seen a main go on these without a rod bearing failing first.
It is a possibility that you would see an increase in compression on a cyclinder that has a spun bearing as it (the piston) comes very close to smacking the head due to the extra travel, most times they will actually hit the head. By increasing the quench area it is effectively raising the compression, adversley if the bearing is stacked compression will be lower because as the piston travels up and detonation occurs the assembly is hammered back down by the force, making the infamous knocking sound.
My thoughts are to check wth a mechanical gauge. Drain the oil look for metal flakes. Go from there. Sounds like it may be time for a rebuild tho!
Without knock being present then a rod bearing would be hard to say, as well as any bearing for that matter. The thing is these have very tight clearances as is and most likely damage is already done no matter what caused the condition. I have seen a clogged oil cooler do the same, as well as a lost pick up off the pump, bad pump and of course rod bearings, never seen a main go on these without a rod bearing failing first.
It is a possibility that you would see an increase in compression on a cyclinder that has a spun bearing as it (the piston) comes very close to smacking the head due to the extra travel, most times they will actually hit the head. By increasing the quench area it is effectively raising the compression, adversley if the bearing is stacked compression will be lower because as the piston travels up and detonation occurs the assembly is hammered back down by the force, making the infamous knocking sound.
My thoughts are to check wth a mechanical gauge. Drain the oil look for metal flakes. Go from there. Sounds like it may be time for a rebuild tho!
On The Tree
Joined: Aug 2006
Posts: 173
Likes: 0
its normal don't trip. next time, don't replace a sensor for no real reason. (you'll know when one goes out) i would take the new one back and put the old one back in, and there's money for your next oil change.... or gas!! lol
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Verdad Gallardo well im talking at idle its literally dropping to nothing when it gets warm...
and it was hooked up to a mechanical gauge as well to verify...
im trying to figure this all out because my car is actually at home and i am at college, and my mom is the one running all the messages to me, and she has no idea what shes sayin...
but i know that yesterday they hooked it up to a mech. pressure gauge at the shop and ran it for like 20 or 25 min.... and mom told me that they said it seemed like it was running fine... but today she calls me and says that we have bad news and they said that they replaced the sending unit and that didnt fix the problem, and they said that its either the pump or a bearing... so i was guessing they were talking about the main bearings because ive heard that is a problem associated with the oil pressure in these cars... but ill try to get ahold of her later and see what is goin on for sure, or just call the mechanic and see what they say for sure
and it was hooked up to a mechanical gauge as well to verify...
im trying to figure this all out because my car is actually at home and i am at college, and my mom is the one running all the messages to me, and she has no idea what shes sayin...
but i know that yesterday they hooked it up to a mech. pressure gauge at the shop and ran it for like 20 or 25 min.... and mom told me that they said it seemed like it was running fine... but today she calls me and says that we have bad news and they said that they replaced the sending unit and that didnt fix the problem, and they said that its either the pump or a bearing... so i was guessing they were talking about the main bearings because ive heard that is a problem associated with the oil pressure in these cars... but ill try to get ahold of her later and see what is goin on for sure, or just call the mechanic and see what they say for sure
yeah id say for sure i do 
...
i think my thoughts on trying to fix this are gonna go this way... but tell me if this is a bad idea... first of all, im gonna replace the oil pump and see if that fixes the problem... and if its not, and i do have to rebuild the motor, at least i have a brand new oil pump on the fresh rebuild... would that be a good way to go about it? or could it be something besides internals or a pump?
...i think my thoughts on trying to fix this are gonna go this way... but tell me if this is a bad idea... first of all, im gonna replace the oil pump and see if that fixes the problem... and if its not, and i do have to rebuild the motor, at least i have a brand new oil pump on the fresh rebuild... would that be a good way to go about it? or could it be something besides internals or a pump?
On The Tree
Joined: Aug 2006
Posts: 173
Likes: 0
lol why not just put a nice engine in now... you dont have to go over the top, just semi-stock. cause you're gonna start to spend a bunch of coin on labor why not just take a big leap forward?... its up to you though
well like what would i go with? ive thought about looking for a crate, but all the lt1's are crazy expensive for like right at stock numbers, and with an ls1 id have to get all the supporting **** to go along with it to even make it run.. i actually could get a ls1 with like 20k on it for somewhat cheap, but it doesnt have any of the wiring or any of that stuff with it, so i would basically spend a lot of money for little ****
ive also thought of rebuilding the car and doing some mild upgrades to it, like a small cam, torque converter, 1.6RR's and valve springs... maybe even the whole hot cam kit... but i just dont know what route to go there
Teching In
Joined: Mar 2008
Posts: 19
Likes: 0
From: Iowa
The question here is how well the car has been treated. 150k is alot of miles, since i would guess you probably weren't the first owner you dont know how it was treated before you got it, but when an engine gets beatin on frequently,(especially at 150k) your set on getting slap in the bottom end. Unless this happened overnight where you had ok pressure yesterday and none today(is it still being driven?) then i would suggest your bottem end is weak. also my 96TA only has 80k and it has very little pressure after warmed up.
well i dont drive it very hard... dunno about the old owner either, but im guessing it was driven pretty hard and not taken care of too well after i have had to do maintenance on the car and i find random **** just mishandled... like how my antenna wire going to my stereo was cut in half and taped back together... or the speakers were all wired by telephone wire.. like literally telephone wire... and how they just left all the amp and sub wiring laying around and not clean looking at all... i found a wrench laying in a somewhat hard to reach spot in the engine bay... just stuff like that leads me to that assumption... but ive treated the car well so far
anyone know where i can find a crate motor for somewhat cheap? and if not, what about a rebuild kit or something like that? i just want to get this car back on the road, and id like to have a sound running motor, not one that is gonna break down and lock up lol
