The car has 94,000 and all services and recalls have been done.
It happened twice in the past two weeks. It doesn't stall but rpm goes down.

 

any engine check lights?/

 

No warning lights.

 

its gonna be hard to tell. you said RPM goes down.. any numbers? like below 500, 400 or even 200.
could be minor electrical issue. I had on mine. Mine used to stall and then died. it was loose ground to ECU.
i don't think you have same issue. I can list few things, Try cleaning your MAF first.

1- alternator is going bad.
2. Dirty MAF. Try cleaning it.
3. Faulty O2 censor.
4. Some electrical connection issue.

 

I used seafoam in my car recently because it would bog down every now and then and start shaking at stop lights. Not rough but would idle around 500rpms. Since then, its been about 2 months since I had a bad idle

 

How do you do that? I am not familiar with seafoam.

 

One full bottle in a full tank of gas is the quickest option. (there are plenty of fuel injector cleaner gas tank options). Seafoam cleans some of the valves when fuel sprays in.

You can run a half bottle in your oil before an oil change. Cleans out the gunk in your crank case. And a little less than half through the brake booster.

I've noticed that, the OEM ticking from the fuel system is quieter than it was before seafoam.

When you do it through the brake booster, your car will smoke for a little bit but that means its working. Not my video but example

 

How will the DI system affect the seafoam system? Is this as needed with the 350?

 

I've seen both + and - results from using SeaFoam; I'm still on the fence about it.

 

Have you changed the spark plugs? And if so how long ago?

Mine started doing something similar at around the same mileage. It started bogging down once in a blue moon, and progressively got worst. Until it was almost undriveable.

It ended up being the spark plugs, O2 sensors and, air fuel mixture sensors.

 

Take it in and have it scanned. Not all trouble codes will set the Check Engine light.

 

I am not sure about the spark plugs. I will have them checked.