Oil Pressure warning light???

[TD_Bunny]

Hey there, I am trying to figure out if i have a sensor that is not working correctly or if my oil pump is not keeping up. After coming off of the interstate going 65mph my Oil Temp light will kick on and start buzzing. This only occurs while i am slowing down and then the light goes away. Also, after running in the higher rpm range for a while it will continue to come on even when only slowing down going 45mph or less. However, when i am driving around town I never see the warning light regardless of how fast i speed up to 40 or 45. It seems with my turbo fully spooled for any length of time is when this problem arises.

Should i concerned with the oil pump or just a faulty sensor? If it is a sensor i should be checking first then is it the one above the oil cooler mount? Engine is a 1.7L TD. thanks

[Vincent Waldon]

Troubleshooting info here:

http://vincewaldon.com/index.php?option=com_content&task=view&id=40&Itemid=28

[TD_Bunny]

thanks i have not looked into the sensors yet but i will.

[TD_Bunny]

2)      Turn the key to “on”; the oil pressure warning light should come on thanks to the lo-pressure sender on the head.  If the light doesn’t come on there’s a problem with the lo-pressure sender, the wiring to that sender, or the dash cluster. A test light between the sensor and the positive battery post should light when the car is off and go out when the car is idling, if the sensor is ok.

okay, when i turn the key "ON" after warming up the engine through at least one cycle i get no lights on the dash. Also, when testing the lo-pressure sensor using a test light, it does light when the engine is off but stays on after the engine starts up.


3)      Start the engine… the oil pressure warning light should go out.

sometimes i have had the battery light and the oil pressure light come on in the mornings when the key is in the "ON" position but both go out at the same time when i simply tap on the gas after the car is on. If i start the car without tapping the gas both lights stay on and dont go "OFF".


4)       Slowly rev the engine up to 2500 RPM… the light should stay out and the buzzer should be quiet.  If the buzzer sounds you need to troubleshoot the hi-pressure system:

with everything connected i can rev up to 2500 or 3000 all day long and no lights will come on so i guess i am good here. However....


d.      A test light between the sensor and the positive battery terminal should be off at warm idle and come on as you rev the engine, if the sensor on the flange is working properly. If the buzzer still sounds with the wire to the sensor grounded the problem is most likely the wiring to the cluster or the cluster itself.

when using a test light again, it stay lit when the engine is idle



I should also note I do not get voltage to my AC wire lead even with the AC switched on. I only note this because it is coming from the same section of the harness so might be related??? I am getting power to my pump solenoid so that is good but it seems my wiring in this area is a little screwed up so if anyone can provide some pics of the wiring in this area I would appreciate it.

[Vincent Waldon]

Yup, we're talking about the oil pressure light here for sure.

OP: the sensor on the head definitely failed the test, and I can't be sure based on your description, but it looks like you tested the sensor on the flange and it stays closed as well.... even at 3000 RPM?

The sensors are cheap, and you know the one on the head is bad, so I'd start there.  As per my HOW-TO I always recommend getting a pressure gauge on the engine asap so that you know for sure you don't have a pressure problem.

[TD_Bunny]

There isn't any oil temperature warning light.

ehhh, i know now but I can not change my original title to the post  

if you read my response Vincent you will see i have moved on from my incorrect assumption on what it is and am now trying to figure out why my pressure switches are signaling problems. thanks for checking though.



thanks Vincent and will-do on the testing of the pressure gauge. the 3000rpm was approximate since i don't have a tach just a hunch from when it would kick on when testing with the hi-pressure sensor unplugged which you had said comes on at about 2000rpm. Just listening to the engine from there.

[Vincent Waldon]

the 3000rpm was approximate since i don't have a tach

Yup, "approximate" is fine here...  what you're looking for at the filter flange is a sensor that is open at idle and goes to ground when you rev the engine up.... 3000ish.  If your sensor stays open or stays grounded then it's time for a new one!

[TD_Bunny]

There isn't any oil temperature warning light.

ehhh, i know now but I can not change my original title to the post  

Yes you can change the thread title.  Go to your initial post and hit the modify button and change the title.

You learn something new.... thanks libbybapa and correction is in place