Low oil light

[tan's2002kjlimited]

Had work done last Saturday on the brick. Oil change(free, over $100 of work) was also performed. Thursday, coming home from work, everytime I stopped for a red light the oil light came on. It went off when in motion. Went back to Midas and had them check. Oil level and pressure were fine (so they say) but as a precaution they re changed the oil and put in 10w30 instead. Test drove it and all was good. Came on a couple of times yesterday just coming home from work, but not today. Could I be developing a bad sensor switch? Any thoughts on this welcome or else I get (to pay someone) to change the sensor switch.

 

[2003KJ]

Probably just just the oil pressure sensor going out if you're not hearing any funny noises like knocking or anything....BUT....

Go get a mechanical gage and hook it up in place of the sensor (search around here...i'm almost positive it's been covered before) and verify that there is in fact sufficient pressure. If memory serves, the 3.7 has some freakishly low curb idle pressure on a fully hot engine. If everything checks out per factory spec, replace the sensor.

 

[Marlon_JB2]

Wasn't it 4 PSI, Tim?

 

[2003KJ]

It's something like that....somewhere between 2 and 4psi is well with in spec....but if you ask me, that's WAY to low.

Problem with dummy lights are once the light comes on, if it's coming on for an actual problem, it's too late. Here's a prime example taken from the 2002 FSM for the KJ regarding the oil pressure lamp:

Engine Oil Pressure Low Message - Once the engine has been started (engine speed has been greater than 450 rpm), each time the cluster receives three consecutive messages from the PCM indicating that the engine oil pressure is about 4 kPa or lower (about 0.6 psi or lower), the low oil pressure indicator is illuminated. The indicator remains illuminated until the cluster receives a single message from the PCM indicating that the engine oil pressure is about 76 kPa or higher (about 11 psi or higher), or until the ignition switch is turned to the Off position, whichever occurs first. Once the cluster monitors and engine speed of greater than 450 rpm, the cluster logic will ignore engine speed in determining low oil pressure indicator operation for the remainder of the current ignition cycle.

 

[Dave]

So Tan, you are running 10w30 oil you said. Mine is an 05 MY and the oil fil cap says 5w30. My owners manual says 5w30 preferred and 10w30 ok in warmer weather. Yours is an 02 MY. Does it say the same? I wonder if it makes a difference?

Dave

 

[JeepJeepster]

Doesnt really make a difference. 10w-30 may cause alittle extra wear and tear on the upper end of the engine on really cold starts along with some valve train noise.

I ran 10w-30 for 3 years then switched to 5w-30 in the winter for the first time this past fall. Its definitely not as loud on cold start-ups.

Ill still run 10w-30 in the summer.

 

[Marlon_JB2]

Well Chrysler designed the engine, so if that's sufficient oil pressure for the engine, then well...... that's just the way it is.

This is sounding like a sensor issue either way.

Now if the Liberty was using Chrysler's 2.7L engine.... then uh... yeah we might have some real issues here.