oil gauge needle jumps

[Fenyx07]

I just got a 99 Ranger XLT...it has some minor issues that need to be tweaked, but hopefully nothing major wrong with it.

I drove it 300 miles home after buying it and noticed the oil gauge was sitting about in the middle (between L & H) and then would suddenly start bouncing up and down quickly, from all the way to the top to the bottom. It would settle down and eventually either end up back in the middle or all the way at the bottom. This happened periodically throughout the drive. Doesn't seem like anything else is wrong so I'm guessing it's maybe a gauge or sensor issue, but not real sure where to start.

Any help?...didn't see this otherwise in the forum.

Thanks!

 

[Earl43P]

The oil pressure sender is actually an 8 psi pressure switch.
It is located on the back (firewall side) of the passenger side cylinder head, best seen with your wife's compact mirror. I'd start by replacing that, especially if it only acts up at idle.

If it is doing this at high(er) rpm, I'd get concerned that oil pressure is actually going below 8 psi. That could be anything from a bad sender, bad oil pump, debris clogging the oil pump pickup screen or worst case a failing CMP synchro. That CMP is installed where a conventional distributor would be (remove intake manifold to replace it). When the CMP gear deteriorates, you lose the drive gear for the engine oil pump and catastrophic engine failure results very quickly.


Welcome to The Ranger Station!

 

[Ranger Sport Honduras]

first, welcome!!, my 99 has something like that, mine when starting cold, the needle stays dead for a while, then when the engine warms up it goes up to normal, i did an engine flush to see if cloggin and im using lighter oil now, and stays the same, maybe the sender is failing??, whew si ti located?? and its to hard to replace/clean?? mine is 2.5 4cyl
thanks!!

 

[Hawk1339]

It is true that the stock pressure sender is only a pressure switch. The gauge has a series resistor that makes for a half scale reading whenever the pressure is greater than 6~8 PSI.

There are previous posts here and elsewhere discussing the modification to a true pressure gauge. It involves changing the sender and bypassing the resistor. It's not terribly difficult but it does require disassembling the dash to remove the instrument cluster. Do a search of this forum, or see page 8 here:

INSTRUMENT CLUSTER SWAP

More info here:
http://rogueperformance.com/oilsw.html

 

[Ranger Sport Honduras]

thanks!! but what i need is to locate the sender to replace/clan it, and leave it stock, when starting in cold, it need like 3minutes to go up!

 

[Hawk1339]

thanks!! but what i need is to locate the sender to replace/clan it, and leave it stock, when starting in cold, it need like 3minutes to go up!

On a 93-96 2.3L engine, the pressure sender is located on the left (drivers) side of the block, at the rear, just below the corner of the valve cover. It is likely in the same place on a 99.

 

[Ranger Sport Honduras]

oo thanks a lot im gonna check it tomorrow, and see i i can take it out to clean, maybe that can help

 

[Ranger Sport Honduras]

On a 93-96 2.3L engine, the pressure sender is located on the left (drivers) side of the block, at the rear, just below the corner of the valve cover. It is likely in the same place on a 99.

didnt find it

 

[Hawk1339]

didnt find it

See here:

DIAGRAM

 

[Ranger Sport Honduras]

mine donest has anything there maybe in the 2.5 ti was relocated, thanks a lot anyways!!