AU Falcon random drop in Oil pressure.

jason18, Nov 1, 11:38pm
Every so often. Happened 3 times in 6 months of ownership.2 of those times were today. It only happens when towing the cherry picker. The oil gauge with drop just above red and then the oil light will show and beep. Touch the go pedal and it will go back up and then stop beeping. Keep driving sweet as. Stop at interesection and it drops right back down and about 15 seconds it shows oil light and does a beep. I shut it off. Check oil and its just below half.

Have now filled oil up and restarted car and its sweet as idling pressure stays up higher on the gauge. Am I looking at a dirty oil feed pick up or my oil pump maybe needing replacement!

Any other ideas!

jason18, Nov 1, 11:39pm
Oil was on the OK mark on dipstick. Only used less than a litre to get to fill mark. Its the 4lt Auto

skyline_guy_r34, Nov 1, 11:54pm
Id say simple case of oil level was too low.

jason18, Nov 2, 12:09am
But it wasn't exactly low it was.on ok

skyline_guy_r34, Nov 2, 12:14am
The oil doesnt need to be low on the dipstick to be too low for a heavy load on the engine. When towing your asking a lot more of your car, even if you only added 400-500ml to fill it back to the full mark, thats still half a litre less oil than you should have had in your engine, and thats a lot when you think about it.

phillip.weston, Nov 2, 12:19am
most engines will still provide ample oil pressure even if they have up to a liter less than the lowest mark on the dipstick. It should not have low oil pressure with a near full sump. I would look at a possible blocked oil pick up or a faulty oil pressure relief valve.

mm12345, Nov 2, 12:39am
Are there separate senders for oil pressure warning and pressure gauge or "all in one"!
If it's a single sender, then they do play up, and can be quite expensive to replace ($200 or more).Inside the can they have an expanding diaphragm connected to a lever which slides up and down over a resistor coil. Over time, the contacts can get manky, you'll lose signal to the gauge - but as the gauge needles are usually heavily damped, the needle doesn't jump quickly all over the place, but is erratic. Some senders are vented, and if so it's possible to squirt some CRC up the vent to get inside - this can fix intermittent problems.
But you need to know exactly what's going on.The symptoms, if correct and not due to a faulty sender, are serious.If it's a separate sender for warning light and gauge, then you've got a red alert to check out suggestions posted by others above, oil pick-up, relief valve, pump.

kingfisher21, Nov 2, 1:11am
Sender unit, replace.

jason18, Nov 2, 1:39am
Where do i find such sensor on this engine

jason18, Nov 2, 2:16am
Cheers Fish. Yeah its done it 3 times when towing. Thing is I tow all the time so I thought it would do it all the time if its something actually bad. Today had towed for a good part of the day then it was after about an hour half park up (doing billboards) I started it up and started driving for about ten mins then it did it.

jason18, Nov 2, 2:46am
oh k cheers man. Thanks

jenny188, Nov 2, 4:18am
Sitting in an armchair but I would be thinking that if it only happens when towing, the oil is getting warmer than usual as motor is working harder. This thins the oil out slightly more and causes the pressure to drop. Giving low pressure. Back in the old Valiant days ( and with holdens and fords of the 60/70's) this was a sign of worn bearings and high milage. Should get worse as the warmer weather increase.

johnf_456, Nov 2, 4:38am
As above check the basics first, what grade oil are you running in it!

jason18, Nov 2, 12:37pm
Running 10w 30 in her.

msigg, Nov 2, 1:11pm
I agree with you jenny, also with the heavy towing and so hot when you come to a stop the engine idle drops below normal for a moment.

unbeatabull, Nov 2, 1:17pm
As mentioned, replace the sender unit first. I've had a couple that would only play up on really hot days (Summer), but then on a cold day would read normal again. If nothing else, its the cheapest thing to start with.

And also check all earths as mentioned.

jason18, Nov 2, 2:44pm
Its wierd tho as I can tow for say 4-5 hours Taumarunui and back then tokoroa, Te Kuiti etc all in the same day. I tow for 15 mins then do billboard tow again for 15 then it starts doing it.Will replace sender unit first and see what happens. Will also do oil and filter. Cheers

johnf_456, Nov 3, 12:38am
Good luck, let us know how you get on.

jason18, Nov 3, 2:53am
Yeah will do. Probably just do what I usually do. Nothing lol

johnf_456, Jan 26, 5:14am
That's not the attitude to have, do it!