Oil psi drops to 5 psi under hard braking - help
09-08-2008, 08:12 PM
#1
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Thread Starter
Join Date: Oct 2000
Location: Wayne, NJ
Posts: 191
Oil psi drops to 5 psi under hard braking - help
This weekend I drove about 200-250 miles completely problem free.
Last night I hit the brakes hard and noticed the oil psi guage drop very suddenly down to about 5 psi and the "check guages" light came on. I let off the brake and tapped the gas and the guage went back up to just under 40 psi.
This has never occured before. Car ran completely fine.
I drove a bit more, hit the brakes to test it again and oil psi guae dropped again. This time I hit the gas pedal before it had a chance to go so low. At idle oil psi sits at around 40 psi.
I drove to work and home problem free. While the engine was cold I was seeing about 45 psi - once warm just a bit under 40.
When I give it gas it goes up to 50-55 psi
I went out to test it again and same thing, hard braking and the psi drops.
Hard acceleration - psi does not drop.
Hard left turn - psi does not drop.
Hard right turn - psi does not drop.
Hard braking - psi drops????
I have a 96 Trans Am A4 w/ 113XXX miles
Basic mods - full exhaust, intake, a tune, ignition, mildly ported heads, 1.6 roller rockers, etc.
It's my daily driver. I don't beat the hell out of the car - just a nice daily driver to cruise in. It rarely sees over 4,000 rpm's. It has seen the track maybe 3-4 times for maybe a max of 12 runs?? I've had it for 1.5 years and oil psi has always been fine.
The original owner always ran royal purple oil - I have continued that.
I checked the oil levle and it is fine.
Any idea what is going on? I find it really odd that oil psi would suddenly drop to 5 psi under hard braking?!?!!
Thank you for any help!
Last night I hit the brakes hard and noticed the oil psi guage drop very suddenly down to about 5 psi and the "check guages" light came on. I let off the brake and tapped the gas and the guage went back up to just under 40 psi.
This has never occured before. Car ran completely fine.
I drove a bit more, hit the brakes to test it again and oil psi guae dropped again. This time I hit the gas pedal before it had a chance to go so low. At idle oil psi sits at around 40 psi.
I drove to work and home problem free. While the engine was cold I was seeing about 45 psi - once warm just a bit under 40.
When I give it gas it goes up to 50-55 psi
I went out to test it again and same thing, hard braking and the psi drops.
Hard acceleration - psi does not drop.
Hard left turn - psi does not drop.
Hard right turn - psi does not drop.
Hard braking - psi drops????
I have a 96 Trans Am A4 w/ 113XXX miles
Basic mods - full exhaust, intake, a tune, ignition, mildly ported heads, 1.6 roller rockers, etc.
It's my daily driver. I don't beat the hell out of the car - just a nice daily driver to cruise in. It rarely sees over 4,000 rpm's. It has seen the track maybe 3-4 times for maybe a max of 12 runs?? I've had it for 1.5 years and oil psi has always been fine.
The original owner always ran royal purple oil - I have continued that.
I checked the oil levle and it is fine.
Any idea what is going on? I find it really odd that oil psi would suddenly drop to 5 psi under hard braking?!?!!
Thank you for any help!
Last edited by 12secondv6; 09-08-2008 at 08:22 PM.
09-08-2008, 08:49 PM
#2
Registered User
Join Date: Oct 2000
Location: Livonia, Mi
Posts: 1,665
First off, royal purple is the devil.
With that out of the way, I would be willing to bet that for some reason under extremely hard braking the oil sloshes in the pan away from the pickup, it sucks in air and you momentarily lose pressure.
With that out of the way, I would be willing to bet that for some reason under extremely hard braking the oil sloshes in the pan away from the pickup, it sucks in air and you momentarily lose pressure.
09-13-2008, 10:33 PM
#5
Registered User
Join Date: Feb 2007
Location: smithtown, NY
Posts: 1,097
idk if it drops and you still have like 35-40 pounds i wouldnt be that worried about it honestly. alot of lt1s dont ever even make that much. on a car i used to have ( lt1)it would have 10 lbs at a hot idle and i never had a problem with it
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