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Discussion Starter #1
so my '90 bronco with a 351w e4od starts great, runs well and has great oil pressure when cold. as soon as it warms up it drops low enough that the check engine light comes on. this is only with low RPMs, if its being driven or revved then the oil pressure returns.... i'm dealing with this 3rd person from half way across the country and i really have no idea. anyone?
 

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Um... so what are you asking?

Yeah sure, if the engine is worn, you may have an oil pressure problem. You can try going to a heavier weight oil, like 15w40, or 20w50 if it's that bad, but just realize that you've got an old motor with wear on it, and nothing is gonna fix that except for a rebuild.

You should really have a mechanical or aftermarket oil pressure gauge on there to actually see what it's doing. The stock one is more of just a switch... 5 psi or less, and it shows nothing. 6 psi or more and it registers.
 

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Discussion Starter #4
well i was going to try a heavier oil with lucas but just wondering if anyone had any other ideas first.
 

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Get a mechanical gauge on it first, and thats BEFORE you go to a heavier weight oil.

Probably a pluged up oil pickup tube, gears could be finally going bad in the pump also, but I doubt that if it pumps the light weight warm oil.
 

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Discussion Starter #6
so i've never even sat in the bko since i bought it online while deployed and haven't got to make it back home yet and i'm dealing with this through my family half way across the country. anyway, my brother is telling me that this is a guage and not just a dummy light, it is pumping the oil cold and warm, its just that it will only maintain oil pressure once warm at higher than idle RPM, doesn't matter whether its driving or in neutral, as long as the RPMs are up the oil pressure is good. i think the oil weight makes the most sense to me because i can't figure how there could be anything clogged when it has good pressure when cold...
 

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I have a problem that is almost the same.

But mine is:

When its cold out the oil pressure gauge stays pinned at low but the truck runs fine.

Then after a few mins the pressure goes up, but if you give it the gas the pressure gauge goes down.

But when the truck warms up it is fine.

Any suggestions?
 

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Okay, you get credit for searching, but not very hard. A little bit more digging and you would have found that:

Your stock oil pressure gauge is NOT an oil pressure gauge. It's a dummy light, either you have 6psi or more and it registers anywhere it feels like on the gauge, or you have 5 or less psi, and it doesn't show anything.

Put a REAL MECHANICAL oil pressure gauge on there to find out what your oil pressure really is.
 

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I read that a few posts up.

Just making sure it wont hurt the motor by running that way.

I am new to the fords sorry.
 

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I don't think you're quite grasping it yet... you don't KNOW that there isn't damage being done until you either troubleshoot your stock system and find that you're getting at least 6psi worth of oil pressure... (still not good)

OR you put a cheap mechanical gauge on there and skip dealing with the worthless stock system all together.
 

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Ford actually has an old TSB on this subject. It involves adding a resistor in the wiring between the sender and the gauge. You should still at least check your oil pressure with a mechanical gauge just to be sure first. I can dig up the TSB if you need it.:chili:
 
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