maplelakeduckslayer

Was thinking more exhaust side

frieed

d'oh
yep, there is that

s_vares

Depends when you check the plugs too.

If they are self cleaning during the normal driving range due to adjusted fuel trims but rich during WOT you will have to read them differently.

maplelakeduckslayer

Well, both sides read about 7 psi back pressure with aggressive driving. Ford says no more than 8 psi at wot. I dunno

s_vares

Any updates on this?

maplelakeduckslayer

Unfortunately really haven't been able to deal with it. I was out of town the last two weekends and bow hunting every week night.


The only somewhat strange thing I noticed taking the back pressure readings, was now the passenger side o2 seems to be getting sooted up more than the last time I pulled it out, last time it had zero soot. But it was dark and I was working with a flashlight so couldn't get a good look.


I am hoping this weekend I can spend a little time on it again, I want to change plugs out before Winter and will do some more investigation/run some datalogs. Thought about replacing the boots and springs in the coils as well, but they are a year old so will inspect and hold off on that for now.


So, not really sure at this point still.

s_vares

Since you clearly can see ST and LT fuel trims, have you tries watching ST and LT on both banks at the same time and adding propane into a vacuum line? make sure data changes on both sides??

maplelakeduckslayer

Yeah they change, drivers side is running leaner which I assume was because of the covered o2 sensor.


Its weird, it seems as if theres a blockage or something. Its just not linear power...its like its a yo-yo. Its hard to describe...but for instance I gave it kind of hard in 3rd gear, it slightly took off good, then backed off, then took off like a rocket(in 3rd gear the whole time). Almost like fuel pressure dropped off, then came back up. I replaced the in tank pump and thought it had helped afterwards, but it still wasn't completely good. I could see weird up and down motion in my fuel pressure in datalogs...the new pump smoothed it out somewhat. But I did that because when I compared my fuel pressure datalog to a buddies Eco, my line looked way way different.


Plan on running another datalog to see if my fuel pressure has reverted back to what it was before. But I think erratic fuel pressure is a result of the sooty o2 sensor, and not a cause of my issues. Pump is 6 months old but you never know.


Going to replace the PCV valve as well


Still curious if this all goes back to the timing chain and phasers, and if the timing is off leading to improper intake/exhaust strokes, which is why the drivers side is getting so sooty

s_vares

I think the soot in the O2 sensor is the symptom and not the actual problem.

If you checked the ST/LT fuel trims can you post some screenshots or a video of this including under load and a throttle snap?

Seeing both banks would help if its not both banks having the issue.

Testing with propane, throttle snap, vac line off, ect shows the O2 sensor can read rich and lean.

The power issues is likely due to the rich condition that clearly exists based on your o2 senor. Question is, what is causing it...

Id say you are coming close to finding the problem, just be very careful not to get sidetracked by symptoms. Spend more time on the fuel trims is different states, this can tell you a lot.

maplelakeduckslayer

Any ideas why when we had a stretch of weather last year around -25 degrees, the trucks ran really good? Is it because with it that cold the truck is not using readings from the o2 sensors very often(not going into closed loop because its so cold)? And using set fuel tables instead of feedback from the o2?