LT1 low oil pressure
Thread Starter
Registered User
Joined: Dec 2014
Posts: 2
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From: Overland Park KS
LT1 low oil pressure I have a 96 z28 Camaro with the LT1 I took it to the shop and had them replace the clutch turn the flywheel delete the smog and a/c change the plugs, wires, and distriubutor, they said that the oil pressure sending unit was also changed because it was leaking, when I got it back on a cold start I would have 50psi oil pressure yet once it got warm it would drop to zero at idle and only 18 at 3500 rpms, the motor eventually started knocking and is now currently locked up. Right before it locked up my mechanic suggested I get the oil changed so I did and Valvoline informed me that my oil filter was barely on however after the change it still knocked and had low oil pressure and eventually locked up. would they change the oil or remove the filter to change the sending unit? also I no longer had heat in the car and they said they had to remove the water pump to change the distributor could a seal have broken causing a leak from my radiator into my oil and caused this drop in pressure?
TECH Fanatic
Joined: Aug 2008
Posts: 1,740
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From: Nebraska
Sounds like that shop screwed some **** up....
#1 if it wasn't knocking or had low oil pressure BEFORE they messed with it, i'd be going back to get some answers. Sounds like they may be trying to screw you over. I feel like they replaced the OPS because they screwed something up and hoped that the new sensor was the issue for low oil pressure.. The OPS is on the back of the motor nowhere near the oil filter so no they didn't have to remove it. And yes you have to pull the waterpump to replace the Opti but it's almost impossible to get water mixed with oil from the waterpump. Antifreeze WILL destroy bearings if ran long enough, usually a headgasket will cause water in oil though before anything.
Either way you're going to need a new motor, but I would go talk to them and get some answers as to why it all of the sudden started doing that. This is why I work on my own stuff....
#1 if it wasn't knocking or had low oil pressure BEFORE they messed with it, i'd be going back to get some answers. Sounds like they may be trying to screw you over. I feel like they replaced the OPS because they screwed something up and hoped that the new sensor was the issue for low oil pressure.. The OPS is on the back of the motor nowhere near the oil filter so no they didn't have to remove it. And yes you have to pull the waterpump to replace the Opti but it's almost impossible to get water mixed with oil from the waterpump. Antifreeze WILL destroy bearings if ran long enough, usually a headgasket will cause water in oil though before anything.
Either way you're going to need a new motor, but I would go talk to them and get some answers as to why it all of the sudden started doing that. This is why I work on my own stuff....
Thread Starter
Registered User
Joined: Dec 2014
Posts: 2
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From: Overland Park KS
well I talked to them and they were adamant that nothing they did would cause this problem. Then again they also replaced the motor in my truck and never even checked the injectors so the motor blew again within 5 days because it was sticking open, they didn't learn there though so when the warranty company denied warranty they spent money out of their pocket having it rebuilt at a machine shop only to have it blow again 2 weeks later, I am supposed to be picking it up tomorrow after they paid to have it rebuilt again! Overall I have been without my truck for 8 weeks so I am pretty sure they fucked it up and I am going to file my own lawsuit but I need to figure out what it is they did.
Staging Lane
Joined: Sep 2012
Posts: 85
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From: Virginia Beach, VA
Not an expert, but your experience with 50 psi at cold start up and only 18 psi at 3,500 rpm when warmed up sounds like the by-pass valve in the oil pump was stuck wide open for some reason reason, e.g., failed spring, debris, etc.
As for the oil filter being "barely on", that sounds like it was removed and then re-installed incorrectly for whatever reason. It doesn't make sense to me either.
Hope that you find out what the real problem was when you disassemble the engine. Be sure to take pictures and/or film it if you intend to use the data as evidence in court.
Good Luck!
As for the oil filter being "barely on", that sounds like it was removed and then re-installed incorrectly for whatever reason. It doesn't make sense to me either.
Hope that you find out what the real problem was when you disassemble the engine. Be sure to take pictures and/or film it if you intend to use the data as evidence in court.
Good Luck!
TECH Fanatic
Joined: Aug 2008
Posts: 1,740
Likes: 2
From: Nebraska
well I talked to them and they were adamant that nothing they did would cause this problem. Then again they also replaced the motor in my truck and never even checked the injectors so the motor blew again within 5 days because it was sticking open, they didn't learn there though so when the warranty company denied warranty they spent money out of their pocket having it rebuilt at a machine shop only to have it blow again 2 weeks later, I am supposed to be picking it up tomorrow after they paid to have it rebuilt again! Overall I have been without my truck for 8 weeks so I am pretty sure they fucked it up and I am going to file my own lawsuit but I need to figure out what it is they did.
