jumping oil gauge

[camkos10101]

when i start up my 3.1 the oil gauge needle (NOT DIGITAL) jumps up as high as it can and stays there. after i drive for a while and then stop at the lights it will sometimes come back to the midranges and bounce around between 1/4 and 3/4 pressure. once i hit the gas again it jumps back up as high as it can go and stays there till the next light. no cluster lights are on. whats the matter with it, adn how do i fix it?

[Guest]

I think that is pretty much normal. As the motor gets older, and the bearings wear down (as well as other things) the car can't keep the pressure like it should. In my 1988 Cutlass (digital cluster) 2.8L with 311,000 miles on it, while I am driving, the guage stays at about 7 to 8 bars (normal). When I first start the car, the pressure is high (about 11-12 bars). After the car warms up, while I am driving, the guages is normal, but when I stop, it drops to 3 bars (when it hits 2 bars, that is when the light turns on). What I would reccommend doing is getting an external oil pressure guage, and hook it up. Start the car, let it run, WATCH THE GUAGE THE WHOLE TIME, and see how the guage responds. Rev the car up a couple of times too. Just enough to make the needle move (if it does). If the guage matches what the cars sluster says, then it is with your oil pressure. If the guage is steady, and does not match what the car normally does, then it is a defective oil pressure sender.

 

you hook the guage up to the oil pressure sender which is located RIGHT NEXT TO the oil filter.

 

Taylor

[STR]

Not normal! Mine did that when I first got the car. You only need to change the sender. Good as new.

[ismellrealbad]

what about if, when i first start my car, the guage stays very high, no matter how much gas i give it. then after it warms up it drops to a normal level and responds properly? Still the sender?

[STR]

what about if, when i first start my car, the guage stays very high, no matter how much gas i give it. then after it warms up it drops to a normal level and responds properly? Still the sender?

 

as long its not jumping around, thats sounds normal.

[88Intl]

when i start up my 3.1 the oil gauge needle (NOT DIGITAL) jumps up as high as it can and stays there. after i drive for a while and then stop at the lights it will sometimes come back to the midranges and bounce around between 1/4 and 3/4 pressure. once i hit the gas again it jumps back up as high as it can go and stays there till the next light. no cluster lights are on. whats the matter with it, adn how do i fix it?

 

My Astro van 4.3V6 oil pressure gauge has always behaved like this. Will replace sending unit one of these days.

 

When I first got my 88 Cutlass 2.8, the digital guage would go down to where LOW lit up at idle, after warmup. Replaced sending unit, now it never goes into LOW . Needed two sending unit sockets, one size for the original, another size for the replacement. Tight fit, had to bend AC line a bit to get socket on sending unit. When buying the sending unit, make sure to specify you have a gauge not just a warning light.

 

:!: Disconnect battery before attempting sending unit removal, the 2.8 sending unit is next to the (+) starter terminal and youll get a faceful of sparks when the socket shorts the battery to ground.

[camkos10101]

The Oil Sender Unit : how do i go about changing it? i bought the Haynes manual and it doesnt show how. can u guys help me?

[Guest TurboSedan]

bouncing around isn't normal, but it is normal for the guage to go up or down dending on engine RPM. when my car is cold it goes to 11 bars, and when driving around (warmed up) usually 7-8 bars. on the highway it is almost always 10-11 bars. sitting at an intersection it will go down to 5 bars.

joshua

[88Intl]

The Oil Sender Unit : how do i go about changing it? i bought the Haynes manual and it doesnt show how. can u guys help me?

 

On the 2.8, it is located between the oil filter and starter.

• 
  1)Drain oil and remove filter.
  2)Disconnect battery
  3)unplug connector from sending unit
  4)get socket on sending unit (AC lines may be in way, I bent mine a bit by hand cause AC dont work anyway, slight risk of cracking it though)
  5)unscrew sending unit to remove
  6)thread in the replacement and tighten (not so tight as to strip threads in block)
  7)plug in sending unit connector
  8)install new filter
  9)fill with fresh oil
  10)start engine and check for gauge reading, leaks
  

 

See my previous post for more details.

[camkos10101]

How many liters of new oil do i put in to fill it up? (3.1L engine)

[Guest Anonymous]

4 quarts

[camkos10101]

that was it