lincolnturns

After some further head scratching + tinkering I had the realization that the symptoms the car began to show were a deteriorating condition. Meaning after all of the late Summer work and systems rebuild the car ran amazing for a short period of time. Reading my post above I had seemingly fixed the issue but alas after a few weeks things went downhill. I pulled the plugs last week and all were fouled - a friend of mine in Denver mentioned maybe colder range plugs would foul quicker if the car wasn't being driven hard/hot?. Went through Rogue tune notes with the PO and started investigating further. Cleaned a few grounds (though all grounding points looked pretty good), put fresh NGK BPR7ES gapped down to .026 and decided to change FQS to setting 2. Pulling 3% fuel across the range I know is a macro adjustment but holy smokes it seems to have made all the difference in the world. To be clear the car ran fine out of boost previously. I could make highway runs, sit in traffic and idle for days but had a major stumble going from vacuum into boost. Leaning things out has now made the car SO much smoother both on decel - and now zero hiccups under load + boost. It feels fantastic - AF/Rs 11.7-12.1 at WOT/15 lbs.

Fingers crossed this not a temp solution as I'd experienced before. I just purchased a fuel pressure tester from Arnnworx to see what the rail reads but I'm hesitant to touch a damn thing now that she's purring!

Dan Martinic

Same older gas? Maybe the "Fuel Quality Switch" is actually meant to compensate for just that: fuel quality lol

If not: I didn't notice it on your list, but have you opened your DME and looked for cracks? They are crazy hard to notice but once you do, you can easily re-heat and add a little solder to fix. Just did this on my DME and it fixed a random stalling issue and as a bonus it seems to respond better too.

This is what the cracks that I fixed look like:

lincolnturns

Whoa. Have opened the DME to look over but not sure I inspected that closely. We'll see how things progress and will absolute look there if need be - thanks Dan.

Dan Martinic