Hi All - Hoping someone can help with a strange problem.

I have a 2015 F150 CCSB, 3.5 Ecoboost. About to hit 105,000 miles.

Over the past year, I've noticed an odd "pulsing" in the throttle/boost. I don't know how to explain it so will do my best here.

When accelerating hard, say cruising at speed and going to pass on highway or speeding up to enter highway, there is a noticeable drop in acceleration and boost. It's very brief, then is normal. But it will keep doing it. So you are gassing it, feel a lull then boost again then lull and on it goes. I first started noticing it when I was pulling my work trailer which is probably ~5500-6200 pounds but it does it without a trailer, anytime you are accelerating hard. I don't drive it hard at all so it's primarily if I'm quickly getting to speed or going to pass someone.

It seems to be something with the turbos but I am at a loss and dont' want to pay a dealer or tech to troubleshoot it without any idea what I'm dealing with (happy to fix myself and prefer to if I can!).

One friend thought it was an issue with the wastegate, but that was all he said. I have always had 7.3s before this so the whole system is quite different and looking for advice on where to start.

There's also a high pitch noise when this happens, not the normal turbo whistle, a bit more harsh than that. I think the noise comes when you're accelerating, and then goes away when the boost drops, then comes back. It's noticeable but not very loud.

Any thoughts or ideas on where to start looking? Anyone else have a similar problem?

TIA

PS - totally unrelated but my trailer brake controller went bad, can anyone confirm if the replacement DOES or does NOT have to be programmed at the dealer after installing?

Thanks again!

 

At a 100k miles and over a year of this drivability issue, if the Turbos go into by-pass or looses boost from a piping fault for any reason , why do you doubt it?
Ever check for any code using a Scanner and not just wait for a Dash light?
Time to be proactive.
Good luck.

 

Could be a bad wastegate actuator. Everyone thinks turbos are complicated and mysterious. They really aren't that hard to deal with. Diesel guys have been doing it for decades.

 

I have checked with various scanners, all quality, no codes pending or stored, no CEL, hence me coming to the forum to ask. This is me being proactive and trying to start with a targeted approach opposed to throwing parts at it when I don't know the root of the problem.

 

Is there a good way to test this and confirm? I know from past projects that the turbos are a pain to get to, at least from underneath.