the other day i started the car up to go to work and the oil psi spiked to the max on the gauge, it's only a mile to work but the gauge stayed at the max until i shut her down. so i get off work and start the car, it was back to normal, around 50 psi. now today it is very low for some reason, maybe 20 psi at idol. parked running at 3k-[IMG][/IMG] why did it spike? and why is it low now? thanks.

 

I'd suspect electrical guage problems; Best get the pressure checked with a mechanical guage to make sure your pres regulator isn't jamming, though.

Maxing that guage should be nearly impossible for the stock pump, though, unless there's a primary blockage.

 

ok thanks, im trying to get the first pic to work, it shows how low it is at idol, around 20 psi.

 

 

check the sender make sure the wire is not gummed up or off. The stock gauge is as worthless as can be though.

 

ok, i went out and cleaned the connection, but it's still doing it.

 

I am guessing here. And pondering....

Is their something in the front mount oil cooler that regulated flow through it, a oil thermostat of sorts? Even though I rarely every read of a problem their, it has been a long time since its inception. Is that a valid pressure regulation point through the system? and potential problem.

 

it has the beehive oil cooler.

 

just a question what is the normal oil psi on idle and driving ? because i believe i have the same problem around 20psi on idle and close to 60 when running....

 

my idol is normal is around 40 psi i think.

 

I'm having the same issue, please some one help us out.

 

Oil pressure gauge spiking is usually a sign of the signal wire going to ground. Normal pressures are listed in Sec. 2 of the FSM. 64-79 psi @ 3k rpm, 12.8-38.4 psi at idle. FMOC has a thermostat that functions in a similar manner as the one in the cooling system. Oil weight and ambient temperature can also affect oil pressure readings when the oil is cold.

 

If you are worried the only way to tell for sure is with a aftermarket one.

 

i'll have to get one then, it's still doing it. and idol psi is almost down to zero. i was driving today and noticed when i hit 3k rpm it spiked to the max, then on the road back to the house it went back to low psi.

 

i'm going to have to say that it's most likely the gauge, i know from experience that these old cars have electrical problems like no one's business. god forbid you're cursed with a digital dash, you'll never know what's going on unless you buy after market gauges. the guy who owned the '85 before me installed an oil pressure gauge, and coolant temperature gauge due to that very fact the stock gauges aren't to be trusted.

 

if that were my car, i think id check the wire (it goes right from the sender to the gauge), and then maybe clean the connections on the cluster.

then change the sender. bad senders usually just read low

 

thats BS. the coolant temp gauge is actually accurate, its just not labeled with numbers.