ericeickhoff

Hey y'all, I have a 2012 FX4 with the 3.5l Ecoboost. I bought the truck a year ago and have had problems with it shuddering/stalling since. I have had it in the dealership 6x which has offered no help.

While sitting at stop lights, stop signs, etc. the engine will periodically shudder. Sometimes it catches and repeats the shudder, other times it stalls. It seems to only do it in the warmer months here in Arkansas which led me to believe maybe it was the CAC I have read so much on. However, I have no issues when driving on the hwy and passing cars. It only does this at stop signs and lights, and it NEVER throws any type of CEL or code to even start to diagnose the problem. Needless to say I am frustrated. The last time I took it to the dealer they recommended changing the spark plugs (please hold the laughter). Which I did knowing this wasn't going to fix anything.

I looked over this forum and only found posts on the 55-60mph condensation issues. Does anyone have a clue what might be going on?? Any help or direction is appreciated. I'm about to torch the truck....

kidastra

iTrader: (1)

Honestly could be your spark plugs, the gap from factory have been known to be all over the place. People in here have had better everything when the replace or regap the plugs.

ericeickhoff

I changed the plugs as they recommended and it did not solve anything. Made sure all gaps were the same and within spec. I just don't see how the plugs would be different based on the different weather.

kidastra

iTrader: (1)

Could be a dirty throttle body, a dirty maf sensor, a bad base idle. Sounds like it could be an air/fuel issue

ericeickhoff

Think it could be due to carbon buildup in the valves? I've seen a lot of posts about this happening.

kidastra

iTrader: (1)

To be honest and blunt, it "could" be anything really, might be a nail in a tire for all we know, I know dumb example, but after 6 trips to the dealer, I'd keep on them to find the problem. No point in starting from the beginning if you've already had them start.

ericeickhoff

Well I dropped it back off today. We will see what they say...

kidastra

iTrader: (1)

Good luck, hopefully 7th time is a charm

TJPlatinumEB

MAP Sensor. Had two friends with similar issues and they tried cleaning theirs and it didn't quite solve it all the way so they replaced it. Problem solved.

stangman39

I've noticed a shudder and somewhat jumpy idle over the last few months also. Never any stalling tho. When it was at the dealer last they said they couldn't duplicate.

How hard is it to change the MAP Sensor?