[95'Formula]

I have a 1995 Firebird formula with a lt1, car has not been abused.
When I start the car cold oil pressure is 40 to 50. When fully warm idles
at 9-15 psi. When driving at 60mph 1600rpm-1800rpm it is at 23 to 40psi.
I am just wondering about the warm idle at 9psi?

I think im going to put a can of seafoam in the gas tank, than a week
later oil change with 10-40w with some lucas oil additive.
Its been about 2300 miles from the last oil change.

The engine has a small tick and hopeing this will resolve the tick.

 

[ShowNoMercy]

That pressure sounds right for the age of the engine.

You could drop the pan, remove the oil pump and install a GM higher pressure spring which would boost your oil pressure at lower RPM's. Thats a lot of work though, so not all that practical.

I would stay away from additives, and sea foam, some people swear by em, but I would rather do a few quick oil changes that dump that stuff in my engine.

Do you have any clue where the tick is coming from on the engine?

 

[95'Formula]

Its from drivers side top of the engine. I think its just 1 lifter

 

[Workman]

Mine has the same tiny tick. And your oil pump itself could possibly be the stock oil pump that came on your car 18 years ago. Trust no mercy's answer he knows his stuff. Or IMHO, just get a new oil pump?

 

[screaminZ]

Regarding your tick, this may sound weird but check your sparkplugs, I had what i thought was a lifter tick but it ended up being a loose sparkplug at the #1 cylinder. It was so loose in my case that i took it out with my fingers, damn previous owner

My lt1 had 170,000 on it before it spun a bearing and i was at the same oil pressure as you

 

[steveo]

you're worried about nothing i bet

9 psi is within factory spec for idle oil pressure and your cold/hot pressure difference is also fairly normal; these cars always have low oil pressure at idle, and they will survive on as little as 2psi of idle oil pressure

the very important thing with oil pressure is, when it's hot, does oil pressure go up with RPM, even slightly? if you throttle up and your oil pressure drops at any point, you have problems. or if you rev from 2k to 6k and there's no increase, you have problems

you can't trust the oil pressure gauge/sender on an LT1. i've seen an lt1 oil pressure sender out by 300%+ and people were almost ready to throw the car away

it's an old car just don't beat on it, it'll probably be good for years like that

all that said, i had a huge amount of fuel varnish and crap in my crankcase from a rich running issue; and my oil pressure suffered (probably from crap on the pickup screen). i cured that with a quart of ATF. would i do that to a really old car with iffy seals and unknown sludgyness? hell no

 

[Workman]

@ steveo, im NOT trying to steal the thread but mine idles at 20????

 

[ShowNoMercy]

@ steveo, im NOT trying to steal the thread but mine idles at 20????

Thick oil, lower miles, colder operating temp etc will all play a role in idle oil pressure.