01_redfire_GT

I did a search and found a few threads with similar problems but I couldn't get a definate answer.

My 01 GT has 66,000 miles and about a week or two ago I noticed that the oil pressure guage would dip way down at idle only and that when I revved a little that it popped right back up. The car was completely 100% stock at that time. It did it just a hand full of times. Well, this weekend I put a MAC CAI on and a BBK 75mm throttle body. Just yesterday the oil pressure guage dipped into the the red everytime I stopped and was at idle. I don't know if this is just coincidence that it went nuts yesterday after I put the parts on or if maybe it had something to do with it.

I got home and let it idle and it the guage started to read low then pop up and it did it several times without me doing anything. The car also seemed to studder a very little bit when the guage read low but it could also just have been me being paranoid.

After the searches, I ran to the auto parts store and replaced the oil pressure sending unit. I haven't noticed it move at all but the temp also went down 30 degrees outside by the time I replaced it. I guess my newb question is, based on what the guage was doing, does it sound like it was the oil pressure sending unit? I would think with 66,000 miles that an oil pump would be a little premature althought anything can happen I guess...

Thanks for looking!

cliffyk

The sensor is just a switch that is ON if the oil pressure is greater than 6 psi (I.e. the gauge is an "idiot gauge")...

It could be that the sensor was bad--keep an eye on the gauge and the oil level for a while. FWIW--I have 100k on my '03 and my brother has 140k on his '99 without oil pump of sensor issues...

5pointslow91

yea just keep an eye on your oil level

01_redfire_GT

Ok, not the sending unit. It did it again today with the new sending unit. It seems to do it more often when it's hot outside and the engine fan is going.... I'm starting to panic a little...

cliffyk

What grade oil are you running, how often do you change it, how long have you owned the car?

What are the ambient temps where you are?

01_redfire_GT

I have had the car for a week now. Just bought it.

The temp outside is around 82 degrees and the previous owner serviced it at Ford on time pretty much everytime. I just changed the oil this past weekend with 5w30 and a fram tough guard filter along with a new fuel filter.

cliffyk

Pull off the Fram Tough Guard and get a Motorcraft 820S (WalMart has 'em here), or a Purolator.

This is from my Miata days, but Fram filters suck and always have high pressure drops across them--on the Miata using a Fram filter would drop the oil pressure by as much as 10psi at idle...

01_redfire_GT

I'll do that this weekend then. Do you think that the oil screen maybe dirty as well causing pressure issues?

If I decide to replace the oil pump to be on the safe side how hard is it to replace it on the 4.6?

v braaten

How does it act when you start it for the first time in the morning? There might be other components that could affect the oil pressure.

cliffyk

I think you are having a panic attack because of a crappy Fram filter, get that off of there first and see what happens.

You may also want to consider, if it rarely/never goes below 30°F where you are, using 10W-30 oil. I have run Pennzoil or "Q" (same thing) full synthetic 10W-30 in my '03 since I got it on Pearl Harbor Day in 2006--over 70k miles and it doesn't burn a drop.

The 5W-20 is much more about fuel economy than engine life. I know I'll get flamed for such heresy, but read this anyway...