Lt1Powerz

iTrader: (1)

When i start my car from a cold start then it reads above 50 psi or so. But as it gets warmer it slowly drops to less than 20 psi... It kind of pulses too, i can watch the gauge move u p and down as it idles... Any ideas?

93v8clone

how old is the oil ?how many miles ? it could be bearing tolerances opened up and ready for a freshen up or sending unit messed up basically put a manual gauge on it and see what it really does if its still low pull it and build it

Lt1Powerz

iTrader: (1)

The oil is like 2k miles old... ANd its Mobil 5000 mile oil... The motor only has 70k on it... I think the switch might be out or going out but im not sure... Where would it be located at because i heard it was a pain in the *** to get to?

1995blacktattop

iTrader: (2)

what year is your car? if its a 95+ it's behind the intake manifold on the drivers side of it. if its a 93-94 its down by the oil filter. mine has been doing the same thing for quite some time. just yesterday i had to switch back to 5w30 from 10w30 since the oil change place didn't stock 10w30. it didn't seem to drop my idle oil pressure any more but i generally am around 10-15psi at hot idle when i used to be at 20. a shop broke my original oil sender when my trans was rebuilt in the fall of 07 and the new one they put in has always read low. i changed it with an autozone one that actually would throw the check gauges light every time i came to a stop with the oil pressure on 0 so i returned it and put the other one back in. i've seen the CG light a couple times at hot idle especially in reverse backing into the garage but it's been over a year and a half since i first ever saw a CG light. other than one time in indianapolis last september when it was really hot out and i was in traffic and saw the CG light almost every time i stopped i don't see it much anymore. i'm 99.9% sure its the gauge/sending unit since if it really had oil pressure that low i would have fried the motor in indy last summer and that was about 4k miles ago.

Lt1Powerz

iTrader: (1)

Okay so now i gotta climb up in my engine bay and find the dang thing and make sure its still there and the wires arent fried before i just go buy another one... Its a 95 California Spec. Idk if that makes a difference but on some stuff it does... Im just glad im not the only one with this problem... Its not like my motor is running any different or anything, if i go WOT then it will hit almost 80 psi. But i havent seen any lights yet... When those come on it will see some shop time lol. Thanks for letting me know im not alone though!

kinglt-1

iTrader: (26)

sounds normal fo a stock lt1. As long as you have pressure and the lifters stay pumped your fine!

1995blacktattop

iTrader: (2)

i don't think cali spec makes a difference on a 95 other than the dual cats. if you reach behind your intake manifold on the drivers side you'll feel it.

Lt1Powerz

iTrader: (1)

Thanks alot guys! I found it and it is not broken or anything so i may replace it and see if it happens again and if it does screw it! Its not broken yet so i think im good!

93v8clone

yeah just give it a good reacharound

RamAir95TA

iTrader: (2)

Take it from me, your oil pressure is absolutely normal. GM spec at idle is less than 10 (more like 6psi). As long as your Check Gauges light isn't coming on, there is nothing wrong with your oil pressure.

Lt1Powerz

iTrader: (1)

Wow. Learn something new everyday... I thought it was supposed to be around 40 psi or so... Wow... Thanks alot man!

kissrocker1200

and what if your check gauges light IS coming on?

letsrun97z

iTrader: (7)

My 97z would set the check gauges light every time I stopped at a light in the summer beat on it like that for 10k miles

kissrocker1200

mines also a 97
are you saying to just let it do that for the next 10k miles...?

transbird95

iTrader: (4)

Are you having the same problem? put a mechanical gauge on it. If it reads within spec you should be fine. If it is below 6-10 pounds at hot idle you might have a problem.

earlz28

iTrader: (1)

my low pressure light comes on after about a half hour of driving, already replaced the sensor. Haven't hooked up a mechanical gauge yet but haven't had any problems running and stays topped off.

SS RRR

iTrader: (2)

Rule of thumb is 10psi per 1000rpm. Sounds like you are good. Those LT1's that have 40psi hot at idle either have a high pressure pump or faulty/inaccurate sending unit/gauge or are using oil of the same viscosity as road tar.

5.slo

My car (95 Z) at hot idle sits at about 20psi. I know the car had the oil pump replaced during the rebuild, dont know the specs on it. Is that high? if so does it mean the car may have a high volume pump?

draggin97s10

iTrader: (2)

A SBC will operate off of 3psi of oil pressure!

litch2004

iTrader: (1)

Mine stock was at about 15 at hot idle, with the cam in it now the stock gauge reads 0 lol. Mechanical gauge under the hood reads at 6-8 at 850rpm idle. So 20 is not low at all.