Noticing a shudder in your 3.5L EcoBoost engine? Shortly after Ford started using the engine in the 2011-2013 F-150 and Expedition owners started noticing the engine shaking, misifirng, stalling, or entering "limp home" mode.
The problem is most noticeable in humid conditions and while driving at highway speeds.
What's Causing the 3.5L EcoBoost to Shudder and Stall? ∞
The problem is likely due to excess moisture building up in the charge air cooler (CAC). The CAC takes intake air from the turbocharger and cools it down before sending it off to the engine.
During that cooling process, condensation is building up within the air intake tube. This problem can be made worse by:
- Humidity or rain, because it increases the amount of moisture in the air.
- Highway driving, where the air flow rate into engine is relatively slow.
Excess moisture is drawn into the engine ∞
When there's a change in acceleration, the CAC's intake airflow rate changes and additional air is drawn into the engine. Unfortunately so is all that water.
As the water mixes with gas and enters the combustion chamber, it can cause the engine to shudder or misfire. If the amount of water is substantial enough it can actually cause the engine to stall out or enter limp home mode.
These problems usually trigger diagnostic trouble codes P0304, P0305, P0306, and P0430.
Lawsuits and Service Bulletins ∞
In May, 2013 three Ohio Ford owners filed a lawsuit claiming the 3.5-liter V6 EcoBoost engine "can shudder, shake and then rapidly lose power while drivers are accelerating."
The lawsuit says more than 100 drivers have complained to the National Highway Traffic Safety Administration (NHTSA) about the V6 EcoBoost rattling or losing power. Although there have been no federal investigations or recalls about the V-6 EcoBoost, the lawsuit alleges that Ford has known about the problem and informed their dealers, but they left the public out of the conversation.
Ford releases bulletin about "Intermittent Stumble and Misfire" in the EcoBoost engine ∞
A few months later, Ford released technical service bulletin #13-8-1 describing these acceleration problems on the highway in humid or damp conditions.
Depending on the version of CAC, technicians were advised to install a revised bottom air deflector onto the charge cooler, presumably to help with the moisture accumulation.
The bulletin applied to the 2011-2012 F-150 3.5L GTDI.