i have a 1993 toyota pickup 4cy man. trans. and when i start the vehicle
the rpm will run about 250 and the oil pressure is quite low (on a scale of
1 to 10 it is mabey a 2 or 3) ,the oil pressure will go up as the engine
accelerates but when it retuns to an idle then it drops again. there is
also rattle when accelerating or decelerating past about 3 000 rpm which my
auto teacher diagnosed as either as piston slap or a loose timing chain i
dont know if that has any relevance to the low oil pressure or not but i
wasnt sure. there are no oil spots that form under the vehicle when it is
parked for extended periods of time. the oil was last changed a month and a
half ago and the recomended amound of oil was put in.
if there are any suggestions on the piston slap or the oil pressure or it the two are related please help. thanks!
I'd suggest you check the oil presure switch first, these are usually located near the oil filter. Wne you changed the engine oil and filter, you wouldn't have damaged it, would you? The reason I ask is that chances are there's not a real problem with oil presure, just a faulty switch :thumbs:
My knowledge has been increasing.
You may not have an oil pressure problem as much as you may be experiencing an idle speed problem.
Low oil pressure will be low by default at 250 RPM.
Your answer lies in your question. :thumbs:
Idle speed on most late vintage cars is 650-750 rpm +- Idle speed issue
needs to be addressed. Fix the idle speed and see if the light goes
Install a gage and measure oil pressure. If it is between 6 and 10 psig @ the correct idle speed and 45-60 psig @ 2500, replace the sending unit or troubleshoot the gage