oil pressure sender issues.

[fishwish3]

i have something similar to problems described above, right in the morning on cold days, about 40 and no problem, below 40 and i start the tuck and gauge says no pressure for about 3 mins after start up and it goes up bounces a bit and then back to normal and its find for the rest of the day, with no death rattle sounds of anything, am i just looking at replacing the sender or oil pump, if sender were is it on a 01 4.0 SOHC sport?

 

[2000StreetRod]

Oil pressure switch

It's actually just a switch (open or closed) instead of a sender. The "oil pressure gauge" on the instrument cluster is just a glorified idiot light. See post #41 in Oil pressure gauge for photos and discussion of the location of the oil pressure switch.

 

[Opera House]

My 02 is acting up for the first few minutes when it is about 10 degrees outside. Replacing the switch is something I don't want to do in this weather.

 

[fishwish3]

sometimes after start-up like i said above it stays above the "L" on the gauge and the check gauge light remains off and pressure slowly starts to build so i dont think that its just a glorified idiot light.

 

[2000StreetRod]

Indicator not the switch

sometimes after start-up like i said above it stays above the "L" on the gauge and the check gauge light remains off and pressure slowly starts to build so i dont think that its just a glorified idiot light.

Below is a photo of the oil pressure switch used in your 2001.

And below is a photo of an oil pressure sending unit that Ford used in their vehicles until the mid 1980s.

The pressure sending unit is much larger in diameter and length and costs more.

Engine oil pressure varies with engine speed. Oil pressure at 3,000 rpm is about twice what it is at idle. If you watch your oil pressure indicator on the instrument cluster you'll notice that it does not fluctuate with engine speed. If your's slowly changes it's probably because the meter movement is dirty or the voltage supply is weak.

 

[Opera House]

fishwish3 is somewhat right. It is a normal gauge with a resistor in series. In the past people have shorted out the resistor and installed a pressure sending unit to have an operating gauge. What he is experiencing is an initial poor contact with resistance that sends the gauge to L. Later a good contact is made and it goes to mid position.

 

[wheadman66]

I have a 99 XLT with 190k and this week was the first time this issue with the no response for the first few minutes then bounces to normal has happened to me. From what I have read here, it looks to be a common issue with the sender unit?

Does anyone know offhand what size wrench you need to change the sending unit?

 

[96eb96]

I have a 99 XLT with 190k and this week was the first time this issue with the no response for the first few minutes then bounces to normal has happened to me. From what I have read here, it looks to be a common issue with the sender unit?

Does anyone know offhand what size wrench you need to change the sending unit?

Harbor freight sells a carded special oil sender socket for like $2 special for this job.

http://www.harborfreightusa.com/usa...o?itemid=95046&CategoryName=&SubCategoryName=

 

[rickuk]

oil sender maybe ?

hoping this is something easy to fix ? when a stop at the lights, junction or stop sign my pressure gauge has started dropping to zero and my warning comes on.
when i accelerate the gauge goes back to normal and warn turns off.
I have replaced the oil filter and did an oil change which was greatly overdue and the problem happened again a week later. there are no noises coming from the engine or smoke from the exhaust. any ideas ?
02 explorer 4.0L

 

[Cobraguy]

Yes...one suggestion. Have the oil pressure checked with a manual gauge so you see if you have a serious problem or not.

 

[rickuk]

oil pressure issue

tried manual oil pressure gauge all was good but couldn't reproduce the problem.....until the next day going to work. put code reader on...no faults found. thinking maybe something to do with the cold weather..bad grounding ??

 

[Cobraguy]

You saw the problem with a manual gauge? If so, you probably have serious engine issues. Time for the motor to come apart and do some investigating. Low oil pressure (provided the oil level is good) is caused by a bad oil pump (extremely rare) or excessive clearances. (usually the culprit)

 

[rickuk]

oil pressure issue

oil pressure was fine when hooked upto the manual gauge......although the problem never appeared while i was hooked up even though it had been doing it 5 minutes before. seems like i have good oil pressure....no noises from engine...and not losing any oil or burning any.

 

[Cobraguy]

Then it sounds like a sender problem. Toss a new sender in there and see if that doesn't cure your problems. If it doesn't, the problem is in the wiring or gauge/cluster. I'd bet on the sender and it's the easiest thing to check.