2005 Ford Mustang: sudden loss of power

Filed Feb 20, 2025 · Engine · OH

I have experienced two engine failures in my 2005 Ford Mustang due to timing chain issues, specifically the failure of the timing chain cassette, guides, and tensioners in the 4.0L SOHC V6 engine. The first failure happened suddenly with no warning, resulting in severe bottom-end damage, including rod knock. The timing chain cassette ends tend to snap off, sending debris through the engine and damaging lifters, camshafts, and other critical components. The second failure was preceded by an audible “death rattle,” a known symptom of timing chain guide and tensioner failure. Despite this, my vehicle never displayed a check engine light or oil pressure warning before either failure. Unlike later Mustangs with an oil pressure gauge, mine only has a warning light, which never activated.This issue poses a major safety risk, especially at highway speeds. My first engine failure occurred with no prior symptoms, which could have led to an accident had I been merging or overtaking. A failing timing chain can cause misfires, loss of power, or sudden engine shutdown, endangering the driver and others on the road. Independent mechanics have confirmed this issue, and Ford service centers recognize it as a common problem with the 4.0L SOHC V6 engine. Ford has quoted $3,000–$4,000 for timing chain service, making repairs nearly as expensive as engine replacement. These engines rely on multiple chains and hydraulic tensioners that wear out over time, causing slack in the timing chain, jumped timing, and catastrophic damage, typically after 100,000 miles. Despite this, there are no clear warning systems to alert drivers before failure occurs. While timing chains are considered serviceable components, the high failure rate of the timing chain guides and tensioners in these engines, combined with excessive repair costs, indicates a design flaw. I have spent around $4,500 addressing this issue, yet the risk of recurrence remains.

Filed Oct 24, 2012 · Engine · 55,357 miles · CT

While driving on local road heard a noise from engine compartment, lost power steering, battery warning light came on and shortly after car stopped running. Found accessory belt detached from pulley. Found out from ford that this was the crankshaft pulley, and this is quite common on the 4.0 v6 engine.

Filed Jul 1, 2010 · Engine · 103,000 miles · IL

Lost power steering when belt came off. The harmonic balancer separated with the pulley part moving 1 1/2" toward the motor taking it out of alignment with the rest of the belt.

Filed Nov 16, 2009 · Engine · 84,885 miles · FL

Lost power steering when belt came off. The harmonic balancer separated with the pulley part moving 1 1/2" toward the motor taking it out of alignment with the rest of the belt. Ford admitted this has been an ongoing problem with the harmonic balancers and there is a nationwide back order on them.

Filed Jan 6, 2007 · Engine, Fuel system · 5,700 miles · FL

Purchased vehicle in 4/05-problems started in 10/05. Engine light on and engine idle rough on 4 separate occasions. Two sensors, a solenoid, and spark plug replaced on those occasions. Now car is at dealer because it will stall when idle and lose power. This is really not safe when you are entering traffic! Still waiting for the outcome of this. The fuel sending unit needed to be replaced due to erratic fuel gauge-the gauge would show empty when the tank was full.

Filed Jan 31, 2006 · Electrical · IL

Complete loss of power when driving in rain in my 2005 ford mustang with v 6 engine.

Filed Oct 12, 2005 · Engine · 6,500 miles · IL

Dt: on october 11, 2005 while driving the vehicle hit a rock. Then, the rock hit the condenser and radiator, causing a leak. This caused the engine to overheat. The vehicle had lost power steering and the brakes. The contact was able to pull safely to the curb. The rock caused a small dent in the radiator. The contact was concerned because there was nothing protecting the radiator from damage. The contact took vehicle to dealer for repairs. The dealership said that the radiator and the motor will have to be replaced. The vehicle was going to be repaired.