2002 V8 oil pressure sender replacement

[galbre]

Hello,
My oil pressure gauge has been bouncing from normal to low for a week. I have plenty of oil and no noise coming from the engine so I think its the sender.

I got under the truck and I cant see the sender. I understand it is near the oil filter but its tight in there as far as space. Does anybody know if you need to remove the filter to get to the sender? I wouldnt have thought so since supposedly you can connect a real guage to that spot while the engine is running to check oil pressure. I just cant see the sender and there is little room to get your hands in there.


Thanks in advance,
Gregg

 

[Turdle]

Bump

 

[galbre]

Bump?

 

[galbre]

I just called the dealer and they want $200 to replace this $12 part which is outrageous. It sounds like it just unscrews so it should be pretty simple. I just cant find it. Does anyone know where it is or even have any pictures?
Thanks,
Gregg

 

[rocket 5979]

The OPSU will be on the lower front drivers side of the engine block by where the base of the oil filter base assembly is mounted. It is a very small sensor usually shaped like a cylinder that is about 1 1/4" in diameter and 1 3/4" long. From my memory it is usually white or ivory colored and has a single wire attached to the very tip of the cylinder. This is all going off of memory from months ago when I had my engine all apart so I may be slightly mistaken, but should be pretty close. IIRC the sensor is not directly attached to the block, but instead has a little bit of a 2" small piping section bringing at away from the block a little. I would not expect that you would have to take the oil filter base assembly off to remove the OPSU.

Overall I would not think this would be a hard job even for a person not very familiar with doing their own work on vehicles. Just make sure you get the old one out, put some liquid teflon thread sealer on the new one and screw it back in nice and tightly and all should be well. One thing worth mentioning is to make sure the threads in the piece where the OPSU itself threads into are fairly clean of debris or old thread sealer as this will hinder fully seating the new OPSU in. The job should take less than 45 minutes if that.

 

[rocket 5979]

It looks like I was mistaking the 5.0 OPSU location for the 4.6. Here is the location of the OPSU for your 02 V8 X according to Alldata Pro. As of right now I would trust Alldata before my occassionally fuzzy memory. Hehe

I would go out and look at my Exploders engine real quick just to verify Alldata but alas I am in Maine again teaching classes for the next two weeks. Just go to your local parts store and pick the new OPSU up, look at that and then look in the area I told you to look and you cannot miss it. Good luck.

 

[galbre]

Replaced sender, still low pressure

Well thanks for all the help! I replaced the oil pressure sender (and the oil and oil filter) but the oil pressure gauge still bounces from low to normal. Now it seems to happen more repeatably when I come to a stop but not always.

I guess it could be:

1) a bad wire from the sender to the gauge on the dash
2) a bad gauge
3) an oil pump. My question is when an oil pump starts to go does it go back and forth from low oil pressure to normal or does it fail completely and you have constant low pressure?

Could it be anything else? The battery/alternator is 5 years old, could that possibly cause it? I am trying to think of things before I rip the dash apart.
Thanks in advance.
Gregg

 

[dave151]

Well thanks for all the help! I replaced the oil pressure sender (and the oil and oil filter) but the oil pressure gauge still bounces from low to normal. Now it seems to happen more repeatably when I come to a stop but not always.

I guess it could be:

1) a bad wire from the sender to the gauge on the dash
2) a bad gauge
3) an oil pump. My question is when an oil pump starts to go does it go back and forth from low oil pressure to normal or does it fail completely and you have constant low pressure?

Could it be anything else? The battery/alternator is 5 years old, could that possibly cause it? I am trying to think of things before I rip the dash apart.
Thanks in advance.
Gregg

My father inlaws 02 explorer just started doing the same thing. It will jump back and forth and sometimes it will even jump up if you step on the gas. I havent' had a chance to look at it yet but the dealer said to check the wire going to the plug. He said sometimes they go bad from the heat.

 

[dave151]

Update:

Well maybe this will help you. I pulled the plug off the sensor and back probed it with a needle. If i test the switch with my mulimeter for continuity while the car is running the switch is closed. With the car off the switch is open. I tried grounding out the connector from the harness and the needle never moved. It's now either the cluster or the wire from the sensor to the dash.

I remeber seeing a few others that changed that wire. GOOD LUCK.