Hello
I recently purchased an EF fairmont.
I took it for a drive, and all seemed alright, i noticed that with the engine warm, and oil pressure guage was showing 1 line above red, but as soon as i drove off, it would go back up to 1/2..
i changed the oil on the car, as there was no service sticker, ran a nulon engine flush, changed the filter with a new ryco one, and whacked in some nulon 15/40 "everyday formula"..
i started the engine, and the oil pressure shot up to just above 1/2, all good.
I went for a drive, and the hotter the engine got, the lower the oil pressure, until at idle in the maccas drive through, when the engine got fairly warm (about 2/3 on the temp), the oil pressure light and buzzer came on, and the guage was reading 0!!!, the engine idles at 700rpm, and if you raise the engine speed to 1000 the oil pressure guage shoots back up to 1/4 pressure...
Any ideas??
Do the senders play up??
Should i perform an oil pressure test??
How many PSI/KPA oil pressure should i have at hot idle??
Do others have this problem with this oil??
Driving the car i have 1/2 on the oil pressure, as i do at cold idle...
Also, the engine doesnt rattle in the lifters, or timing chain, as you would expect for no oil pressure...

Thank you, and sorry about the life story..lol
David

same thing happens to mine occasionally..

Excepts my tappets are very f**k loud and sometimes i can hear a slight whistle sound (time chain). But as u said if u raise the rpm to 1000 the whistle sound goes away and the pressure goes up abit.

This is only when the engine is hot but..


I think i will try a thicker oil and see how i go from there..

cool.
i dont know what grade oil was in this car, but as it only had 210km on the clock, i assumed that 15W/40 would be ok in it..
i think i still might do an oil pressure test on it with a master guage...

thanks
David

My 96 EL I6 had fuctuating oil pressure, low rpm hi press hi rpm low press.
Pu t a new ford sender in( you need a box socket, take new sender to tool store for test fit) I had removed the oil filter as i was changing the oil to 15w40 It was as easy as to change.
Oil pressure now is mid range and follows rpm witha a small increase in pressure, as it should do.

If it idleing at 700rpm bump it up to 800 to 850rpm.

basicly if you gauge is working, your engine has alot of bearing wear. And your oil pump can't keep up at low engine speeds. this is one of the very cases that i would recomend changing from a 15-W-40 to an X-W-50 grade oil

Thanks for the replys guys!
I'll go to ford and get a new sender unit, and try that..
I will also up the idle a tad, it idle's alittle low, and gets the shudders with the A/C on at idle..

Thanks
David