Today out driving, I was cruising along at about 45-50 mph in either 3rd or 4th gear (45 or so is where I get a shift and I wasn't listening to the RPMs, but the gear shouldn't make a difference, right?) and I glanced down at my gauges just quick enough to see the oil pressure needle flutter between where it usually sets and lower than where it usually sets. I don't think that my OP actually dropped to 0, or even into the red L on the gauge, but it got me concerned and I was checking it regularly until I got to my destination. I checked the oil level, it was normal.

The OP gauge read normal the rest of the trip, was this just some minor one time thing, or do I need to follow up on it?

Thanks

Kevin

 

Change out the pressure sender. They are notorious for going bad. They are an on/off switch now thanks to customers complaining about lower oil pressure at idle. If the new sensor still does the fluxuations, time to look deeper... QUICKLY!!

 

If the sender had gone bad, wouldn't it have been sending the fluxuations for the remainder of the drive? It only fluttered once and was normal the rest of the drive. How common is the sender a problem?

 

Man I'll tell ya what...you guys can do what you want, but I'm the opposite. I know that pressure switch goes bad a lot and everyone on here is spring loaded to recommend changing the switch whens someone complains about pressure problems, but my first step is going to be check the engine/pressure problem...somehow. We just recently had a guy on here that got led down this path of simply being a bad switch and guess what...he had an engine problem.

 

I appreciate your concern over an engine problem, but the truck's only got 76,000 miles. I think I'll keep an eye on the gauge over the next few weeks. If the problem arises again, it gets a new pressure sender. If the problem arises again after the new sender, I've got an engine problem.

 

You know, a new sender is only 10 bucks - I'd replace it on general principle.

 

But if you have an engine problem now.. your only doing damage by waiting. I doubt it has an engine problem.. but why take the chance?

 

Ya beat me to it!!!! How many miles on your motor is 100% irrelevant.

 

Is the pressure sender easy to replace, or is it something I should call a shop for? The part may only be ten bucks, but what would labor run?

 

Not hard to replace. Hand tools needed.

 

Usually, IIRC, an open-ended wrech and your hands are all that is needed. That's what mine took.

 

I went to the dealership to get a new sending unit as well as some black plastic rivets, I guess they are called. Got the rivets, good. Heard the price for a new 4.6L sending unit and walked out the door. $50 or so. Lucky I tried the O'Reilly's, they had the part just as you all described for under $10.

Now the stupid part of the question. While I was at the dealership, I asked where I can find the sending unit. They say on the right, above the oil filter. I'm not seeing it. I see several miscellaneous spots that could be it, one beneath the drivers side coil pack, one on top of the driver's side valve cover, but I don't really want to start pulling everything apart until I absolutely have to.

Second stupid question. Although it sounds like this will be above the oil pan, do I need to have a drip pan handy if it spits oil out, or does it only have oil at the sender if the engine is running and developing OP?

Sorry for my ignorance, but I want to take care of this.

Kevin

After looking a little more, is it the one right behind the oil filter?

 

Nah, no drip pan needed. You can thro a couple rags down if you want - If you have new concrete or something you don't want to mess up.

There's only pressure at the sender KOER.

 

Alright, I've found it. I can't get a wrench up in there because of the front axle. Also, I think the new sending unit they've sold me is wrong. The old one looks a lot like the one in the diagram. The new one doesn't look quite like it.

The truck is an early 97, both the label on the block and in the door jamb both say manufactured in March of 1996. Would that make a difference, or is a 97 model year a 97 truck?

 

It's most likely just be an updated part. Make sure it fit's well and has the same electrical connector on the end.