I'm going to try to remember the whole timeline here...
I bought the car on 2/16. Drove 200 miles home, no issues. Tuesday, 2/17, on the way to work, the check engine light came on. I got to work, checked the code, P0521, cleared the code. Did some research and found that the most common issue for this code is bad sensor. Drove home, back to work 2/18, light comes on again on the way home from work. I go home, order a replacement sensor (to be delivered Saturday), drive the truck to work Friday. Sensor comes in Saturday and I damage the valve lifter oil filter (little screen that sits under the sensor). So, Monday I call the parts guy at Herlong, he has one on the shelf, I get it Monday night. I put it in that night, new sensor, went for a test drive and code was pended (would have set on next drive cycle).
This is where the 1) No oil pressure gauge comes in. It doesn't even have a dummy light, just the check engine light. Code P0521 only sets for ecm seeing oil pressure either greater than 128 psi at less than 640 RPM, or less than 1.6 psi at more than 1520 RPM for more than 4 seconds. There is a separate code for "No oil pressure". I decided not to drive it any more until I verified pressure. Tuesday 2/24 DJ brought over an oil pressure gauge kit he had that had never been opened, and we find out it doesn't have the M16 x 1.5 adapter needed. So, ordered a metric adapter kit to be delivered Thursday 2/26. We checked it with manual gauge that night and pressures showed fine. Drove it with gauge run through window...
Put it back together with the new sensor and drove it a few days. It went first drive cycle code pends, second drive cycle light sets, reset code, first cycle pends, second cycle sets...
Wednesday, 3/4, I went by Miller's on the way home and plugged in his fancy scanner. His scanner showed history and said the code set at 60 mpg, 1550 rpm (I'm estimating, don't remember exactly), which would mean the less than 1.6 psi... We watched the pressures at multiple rpms and they were within spec, rose with engine speed, etc... Miller also noticed there were 2 transmission trouble codes stored (#2, no dipstick, no idea condition of fluid...:roll
. Drove it home and code set again. Now I figured out my scanner also shows history and it was the same 60ish, 1550ish...
At this point I remember that initially (with the original sensor) the CEL would come on as I was pulling up to a stop light, at idle, at low speed (so it had to be the other end of the spectrum, > 128 PSI right?
). I didn't have time to mess with it and drove the Jeep for a while until 3/10 I went to swap the sensor back to the original one to see what it did. When I pulled the sensor I wiped the port with a blue shop rag, looked at the rag, ****, metal flake. Pull the dipstick, wipe with rag, ****, more metal flake
issed:. Closed the hood and walked away...
So, fast forward to 3/13. I check the oil in Burgundy's Yukon getting ready to go camping. Wipe dipstick with blue shop rag, ****, metal flake
. So now I'm not sure what I'm seeing because there's nothing wrong with Burgundy's truck. Try not to think about it and go camping...
On to Sunday, 3/22.
I go buy a clean drain pan and pull the plug not knowing what to expect. Pan is clean, no metal. So, change oil and filter, original sensor back in, have made a couple test laps and no codes...
I'm going to drive it tomorrow and see if it sets. As I said earlier I ordered a Speedhut CAN bus gauge so I will be able to see what the computer is seeing but it's not here yet. So, I don't think there's a major mechanical issue. I've confirmed good oil pressure mechanically and off of the sensor.
And #3, who the hell thought it was a good idea to bury the washer tank between the bumper and radiator with no access