Engine- V8 5.2 automatic

After replacing my plenum gasket 1 month ago I believe my oil consumptions problems are over. But now my oil gauge has low pressure when my truck idles and when it's at low pressure I can hear my engine wheezing for oil. However, when my truck is in motion the oil pressure will go up to 50 and stay there until I stop. I also smell a burning smell every once in while but I think it may be my exhaust because it's black as hell because my plenum gasket was leaking.


problem- low oil pressure when truck idles then pressure rises as I accelerate.

Oil pump bad??? pressure switch???


Thanks

 

Yes most likely the switch. Also higher mileage engines do drop in pressure.

 

There is a column casted within the engine from the pump to the sensor that gets caked with soot (carbon) after about 80K or lack of proper oil changes, or straight up fouled with foreign matter. If you have ever had a block "tanked" to clean it, you would be surprized at how much carbon residue still needs to be cleaned out afterward. Especially where the lifters are fed.

Note that where the #5 main oil plug (DS beneath the cap) is located has an effect on pressure as well if it is damaged. However, in your case I would assume the sensor first, then the buildup.

 

I replaced the oil pressure switch today and it didn't change anything. My engine might still be burning oil because my dipstick showed add which means I'm still losing oil. Since I replaced a broken plenum gasket and pressure switch where would the next likely internal oil leak be on a 318?


Rear main seal possible?

 

Look for glossy areas under the valve covers, rear seal, timing chain cover and the corners of the oil pan. Also, your probably due for a pump change since the pressure is related to your RPM.

 

Didn you change oil recently?
Bad filter can cause o/p problems, also burning oil smell, leaking filter seal, or drain plug seal can mist the exhaust and give a smell.

 

I changed my oil when I did my manifold project and that was 1 month ago. I used a Mopar oil filter from advance and now that I think about it I put a small dent in that filter because it fell on the ground.

Could any dents in a oil filter cause problems?

 

Hard to tell, In had one filter that would not allow oil return properly. Had low oil pressure and actually no pressure at one point after standing on it. Pulled that succor and installed new filter, changed oil, problem went away. Filter is cheaper than engine worth a try. Also could the drop have distorted the gasket and is letting oil out onto the exhaust thus a burning smell?