Bad oil pump?
Thread Starter
Joined: Jul 2017
Posts: 32
Likes: 0
From: Fredericksburg, Virginia
Bad oil pump? Maybe somone on here can help me out. 99 firebird ls1 , sitting in standstill traffic for over and hour. Had scanner up to monitor temps hovered in the 220’s 230’s so normal with the fans on. Oil pressure was sitting at 20 which seemed low, then it started to fall to 10 , then would hit 0 check gauges would come on. Bounced around between 10 and 0. Car started missing hard, I had nowhere to pull off. Couldnt hear anything since exhaust is so loud. waited about 10 mins finally got moving. Car felt better and oil when up to around 30-40. Then felt extremely hot in the car , temps still showed fine on the scanner, dropping back in the 190’s as I got moving. Got to my house couple mins later. checked codes had a 1258 code. Code says that kicks off at 268temp , and kills cylinders to save the motor. Makes no sense because I never saw a high temp unless the sensor doesn’t read correctly, also doesn’t explain the lack of oil pressure
Thread Starter
Joined: Jul 2017
Posts: 32
Likes: 0
From: Fredericksburg, Virginia
Also car did throw the belt the day before. It overheated for maybe a minute as I was pulling off into a parking lot. So maybe it already had the 1258 code from the day before
The LS engines have a common issue with the O-ring on the oil pan pickup tube going bad and oil pressure being lost.
The next time, try revving your engine to see if your oil pressure goes up. If so, you might need to change that O-ring. (Unfortunately, if this is your issue, the swap requires removing the oil pan.)
The next time, try revving your engine to see if your oil pressure goes up. If so, you might need to change that O-ring. (Unfortunately, if this is your issue, the swap requires removing the oil pan.)
Thread Starter
Joined: Jul 2017
Posts: 32
Likes: 0
From: Fredericksburg, Virginia
The LS engines have a common issue with the O-ring on the oil pan pickup tube going bad and oil pressure being lost.
The next time, try revving your engine to see if your oil pressure goes up. If so, you might need to change that O-ring. (Unfortunately, if this is your issue, the swap requires removing the oil pan.)
The next time, try revving your engine to see if your oil pressure goes up. If so, you might need to change that O-ring. (Unfortunately, if this is your issue, the swap requires removing the oil pan.)
That sounds like it. I think I have the same issue, but not as bad. (I've read that it starts to manifest itself as low pressure at idle.) I'm looking to tear into it as soon as I can get some time off of work.
Your situation sounds more urgent. I would also watch it and not let the pressure go low until you can get it fixed.
Your situation sounds more urgent. I would also watch it and not let the pressure go low until you can get it fixed.
