General Maintenance & Repairs Leaks | Squeaks | Clunks | Rattles | Grinds

Bad oil pump?

Thread Tools
 
Search this Thread
 
Old 04-29-2021, 08:59 PM
  #1  
Teching In
Thread Starter
iTrader: (1)
 
Jeremy Bragg's Avatar
 
Join Date: Jul 2017
Location: Fredericksburg, Virginia
Posts: 30
Received 0 Likes on 0 Posts
Default 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
Old 04-29-2021, 10:00 PM
  #2  
Teching In
Thread Starter
iTrader: (1)
 
Jeremy Bragg's Avatar
 
Join Date: Jul 2017
Location: Fredericksburg, Virginia
Posts: 30
Received 0 Likes on 0 Posts
Default

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
Old 05-03-2021, 01:20 PM
  #3  
Save the manuals!
iTrader: (5)
 
wssix99's Avatar
 
Join Date: Dec 2007
Location: Chicago, IL
Posts: 12,667
Received 322 Likes on 295 Posts

Default

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.)
Old 05-03-2021, 03:13 PM
  #4  
Teching In
Thread Starter
iTrader: (1)
 
Jeremy Bragg's Avatar
 
Join Date: Jul 2017
Location: Fredericksburg, Virginia
Posts: 30
Received 0 Likes on 0 Posts
Default

Originally Posted by wssix99
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.)
this was also a thought. It did go up if I revved it. I Let it sit for a couple of days, started it and drove down the street. Idled around 20 pounds and would go up around 35 driving around the neighborhood.
Old 05-04-2021, 09:43 AM
  #5  
Save the manuals!
iTrader: (5)
 
wssix99's Avatar
 
Join Date: Dec 2007
Location: Chicago, IL
Posts: 12,667
Received 322 Likes on 295 Posts

Default

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.



Quick Reply: Bad oil pump?



All times are GMT -5. The time now is 06:53 AM.