Stephen_techguy

Hey everyone, 2 weeks ago I purchased a used 2004 F-150 Lariat with the 5.4L Triton Engine and 136k miles on it off of Craigslist. At the time of purchase which was after an intensive day of driving it around Northern Virginia, it had a check engine light with the following 2 codes: P0011-Intake Camshaft Position Timing-Over-Advanced (Bank 1) P0021- Intake Camshaft Position Timing-Over-Advanced (Bank 2). I did not replace those right away, I changed the oil on it using Valvoline High mileage 5W-20 oil and put a new K&N oil and air filter on it. I went through the next week driving it around(getting the Temporary tags, Maryland State Inspection, etc.) and recently just yesterday while driving it around, the oil pressure gauge went straight to "low" and the "Low Oil Pressure" error came on the information screen. I pulled over and shut it off. After a few minutes I turned it over while pressing the gas to the floor and the oil pressure came back up. I drove it for about a mile and then it repeated the problem. I also repeated my steps to get the pressure back up. I limped along until I found a parking lot to put it in. I've seen a lot of post about "timing, ticking, VCT Solenoids, camshaft position sensors" and I'm wondering if for now it's possibly safe to fix the issues the error codes gave me and replace the sensors or if this is a bigger issue. PLEASE HELP!!

adrianjwalsh

The oil pressure gauge in your truck is connected to a binary oil pressure sending unit. So essentially, the oil pressure gauge isn't much of a gauge at all. It reports low oil pressure for one of two reasons. Either the oil pressure is below 8 PSI (the sending unit's threshold), or the sending unit is reporting incorrect oil pressure. A lot of folks with this engine have experienced low oil pressure because of a clogged oil pickup screen, either by pieces of the plastic chain guides, or by sludge. I suggest you verify that the oil pressure is in fact low with an oil pressure gauge, and make sure the oil level is between the high and low marks on the dipstick.

The DTC codes P0011 and P0021 are related to the VCT system, and I am not familiar enough with variable cam timing to comment on that issue. Although, several members here are familiar with it, so you're definitely in the right place. I would like to add that there seems to be a relationship between oil pressure and the VCT system.

In conclusion, I would remove the oil pan and check for debris that may be clogging the oil pump pickup screen, and verify the low oil pressure reading with an oil pressure gauge. Low oil pressure will lead to catastrophic failure of the engine, and VCT problems will not, so it's important to prioritize. The issue is likely not faulty camshaft position sensors. The camshaft is likely overly advanced or retarded due to an issue with oil pressure or the VCT system.