LT1 low oil pressure. Please help
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The car is a 95 Z28 automatic LT1 with 150k miles on it. The problem is the oil pressure is border line to the red mark and sometimes hits it. Turning on the check gauge light. He is currently running 10w 30w synthetic oil. Could it be because of the mileage and the pump is wearing out?? I'm not fimilar with LT1 cars because I usually work on LS1. He had the oil changed about 500 miles ago.
Thanks for your time,
Thanks for your time,
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Check the oil pressure sending unit. its also quite possible that the oil pump is just finaly wearing out or the screen for the oil pump is clogged (unlikely). Disconnect the motor mounts, take off the OPSU, and jack the crap outta the motor. it should allow you to get high enough to where you can drop the pan enough to pull the pump out and change it.
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Before you look into changing the oil pump. Check out the oil pressure sending unit on top of the block behind the intake. Not in a very friendly placed but its better than changing an oil pump if you dont have to. My oil pressure reads close to 0 or at least under 10 if the car has been running for a while. As LT1s put on miles the gauge usually reads a little lower than actual. Unless the motor is acting up, you're probably ok.
Also make sure that for every 1000 RPM, the oil pressure rises 10psi. At WOT the oil pressure should make it to about 50-55psi.
Also make sure that for every 1000 RPM, the oil pressure rises 10psi. At WOT the oil pressure should make it to about 50-55psi.
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Scott offered some good advice, Howver I would also venture to say that there may be ...may....be...problems on the bottom end, also, cold just be a faulty sending unit.....
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Originally Posted by mingoman
Scott offered some good advice, Howver I would also venture to say that there may be ...may....be...problems on the bottom end, also, cold just be a faulty sending unit.....
My homeboy who has the same car has the same problem he said sometimes the oil pump goes out but it could also mean bearing wear. his psi drops when he's ideling and when he takes off it goes back to 40 to 50. Try the oil pump and it dont work might wanna try rebuilding it .
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that isnt enough PSI to be running safely. Your bearings may be wearing out after all the miles causing the clearances to be not so tight thus creating a lower pressure. The pump gears could be wearing out. Generally, when the OPSU goes out, the dial pegs out or the dial will jump erradically(sp?).