Thanks in advance.

Just picked up a too good to be true deal .. and now hoping that it wasn't

Clean '03 P-74 with 140K miles, had it deliveerd so haven't driven it a single mile. A few needs here and there that I was expecting that I was going to deal with later in the week - problem is I'm way out in the boonies, it's -5 and snowing again, and I have a 200 mile commute. Just transferred the insurance so my other car isn't legal after midnight.

Oil pressure gauge is reading near zero - it moves up just a bit (but still in the red) when running.

Previous owner says the gauge bad (I just called him), but hey .. all sales final, right?.

He did deliver it 30 miles, it sounds good. Can't imagine it would have made it here with dry bearings but zero oil pressure is understandably a scary indication.

Nothing on hand and too cold to dive in and make any diagnosis tonight.

Question: Doesn't the ECU monitor oil pressure as well as the gauge? Presumably flashing the MIL if low pressure detected? So it's likely just the gauge, no?

But if so, I would expect a totally dead needle.

My first Ford in 25 years .. I know the 4.6 is an entirely different animal, but I recall oil pump issues with the 302W.

If the MIL isn't lit and it sounds good should I attempt the commute? (If the gauge is accurate then the delivery would have toasted the engine anyway - what's a tossed rod at this point).

In a bit of a panic and wondering what I should do.

If it were warm, I'd tee in a mechanical (capillary) oil pressure gauge and see what the actual deal is, but like I said .. it's winter, getting dark, and I don't have a useful tool set on hand.

Thanks,
Jim.

 

Correction .. the gauge does NOT move at all - sitting below red - key in any position, or running idle to a good deal of pedal. Confirmed that the MIL is working (briefly illuminated at start up).

 

The MIL usually will lite when there is an emission problem.
Did you get a chance to check if the wire is connected to the oi pressure sending unit?

 

No, I'm not familiar with the modular Ford engine - google search has the sender low near the oil filter but with the snow and dark I wasn't able to locate it, or a harness (or wire) heading down in that direction. and not enough room to crawl under and attempt a spy from beneath. Lol, only 200 miles away I have a lift, tools, OBD reader... Stellar timing.

I would expect that the modern inst cluster has radically changed from the era of discreet resistive divider gauges that could be individually tested with a D cell on a sender wire - now serial data sent from the ECU to an integrated cluster?

IMO this doesn't bode well for an individual gauge failure - if half of the cluster, or at east multiple instruments were dead, I'd be less inclined to worry about the oil pressure reading.

On the other hand, what could cause zero pressure, and what's the likelihood of such a failure? Seen old school engines break a distributor drive gear (no oil pump drive), but even severe wear or pump impeller clearance would still build some pressure at revs.

I can't believe that it may come down to a "if it starts knocking, the gauge was correct after all" diagnosis.

 

I don't how the vehicle was delivered and maybe they either knew or didn't care.
Usually just to have piece of mind would pay to have any place either put it on a lift, jack it up, or just manage to get under it to determine that the plug is at least on the sender. As you know it surely would have crapped out by this time if they drove it with really no oil press.

 

With the clarity of a night's sleep I have to agree - it surely wouldn't have gone 30 highway miles with no oil press whatsoever, then idled another 20 minutes. Logic would indicate that it's an instrumentation error. Wish I'd waited to plate it now though - in a few weeks working out the failure (or indeed adding an aftermarket gauge set) would be a downright pleasant day's work. It's got clean oil and a new looking filter .. temp is good - as much as it's against every fiber of my being, I think I'll risk the drive to my shop.

Wish me luck.

I'll keep you posted, thanks for your replies.