"Check gage" light on 2004 Jeep Grand Cherokee

[Duke2000]

Hi all,
I have read your posts on this website and thought you might be the right people to ask the problem that i am facing.

I have a Jeep Grand cherokee 2004 I6 4.0L. For some strange reason, sometimes the "check gage" light comes on and I noticed that oil pressure gauge in dash board is at 0. The light stays on and I parked my car and after couple of hours, when I start the car again, it disappears and the "oil pressure gauge" goes to middle of the scale. Is it the oil sending unit that is faulty or is my oil pump gone? I have't seen any performance difference, but sometimes when its showing 0 on oil pressure gauge i get scared i don't want to fry my engine by driving.
Another thing that I noticed is that oil pressure gauge stays constant in the middle of a scale even when I am driving at 120km/hr or 60 km/hr, shouldn't it move up and down on the guage?

I also could not locate the oil sending unit in my jeep, can you tell me where exactly it is, people told me it is easy to replace.
I will appreciate your help.

Thanks,

D

 

[SteelHeadz]

It sounds like the oil pressure sending unit is failing. It's located on the passenger side of the block near the oil dipstick tube. It's a one wire sensor. Welcome to Jeepz.com.

 

[Duke2000]

Thank you Steelheadz,
I was trying to pm you to ask this question, but since i am a new user, they wouldn't allow pms. I realy appreciate your reply. I called the dealer and its $20 part. Hopefully when I get home from work, i will try to locate the sending unit and replace it. I hope that was the issue, cause it is very scary to drive with that light on.

Another question I had was, whether the oil pressure guage moves while you change the speed. The needle on my oil pressure gage always shows just above the half way mark. Is that normal. Should that needle be moving up and down when you drive at low or high speed?

Thanks for all the help.

Best Regards,

D

 

[SteelHeadz]

Thank you Steelheadz,
I was trying to pm you to ask this question, but since i am a new user, they wouldn't allow pms. I realy appreciate your reply. I called the dealer and its $20 part. Hopefully when I get home from work, i will try to locate the sending unit and replace it. I hope that was the issue, cause it is very scary to drive with that light on.

Another question I had was, whether the oil pressure guage moves while you change the speed. The needle on my oil pressure gage always shows just above the half way mark. Is that normal. Should that needle be moving up and down when you drive at low or high speed?

Thanks for all the help.

Best Regards,

D

Yes that's normal. Most evident after the engine has reached it's normal operating temperature.. BTW, there is a special socket used to replace that sending unit. Napa or carquest might have that socket.

 

[Duke2000]

How expensive is the special socket and do the dealers have that? The dealers are selling me the unit for $20. I am sure the socket wouldn't be more expensive than the unit itself?

 

[SteelHeadz]

You can purchase the socket from your local parts store.

 

[Duke2000]

Thanks SteelHeadz, Another question I had was about the lower belt moldings on door windows which tap on. There is a little steel inside them which is rusted out and its coming out. I couldn't find it anywhere and they say its dealer part. They are each costing $70 from dealers? Any shop you know which sell them aftermarket?

Thanks,

D

 

[SteelHeadz]

Unfortunately no. I haven't heard of any aftermarket source for the belt mouldings or trim gaskets and much more, the clips that retains them. Try the junkyards. You might be able to purchese the belt moulding for cheap an either use the whole piece with the clips or transfer the clip you need off of it.

 

[Duke2000]

Thanks Steelheadz,
I will try the junkyard for belt moulding. I changed the pressure sending switch. Couldn't find the right socket, but was able to use a big adjustable rench! installed the new switch. Now the check gage light is gone. Hopefully it stays this way. Thanks again for letting me know where the pressure switch was located.

Best,

D