1999 Mercury Grand Marquis Engine Problems

“Plastic intake manifold failed, antifreeze leaking from around thermostat due to this failure and leaking into coil packs and causing major misfire in motor. Happened suddenly, no indication of leak prior to this failure. Was driving when this happened and had to call for help to get vehicle back home, and now can't drive it . Cost to fix is expensive, and the car ran great until this happened. Sounded like I has thrown a rod, popping louder on exceleration, so I immediately parked it and turned off the motor.”

“On the 1999 Mercury Grand Marquis ls 4.6 l v8 the original plastic intake manifold cracked and busted wide open causing all the coolant / antifreeze to pour out. From what I gather there was a recall on this years ago and they made a different intake manifold which was aluminum for the part that the thermostat goes into and the rest of it was plastic. If this isn't caught in time and all the fluid leaks out it will completely destroying your engine also. Mine cracked while it was in park just running.”

“Intake manifold failed (burned and disintegrated in the area of the thermostat ) and had to be replaced at considerable expense . Presently the speedometer fails intermittently dropping to zero at random moments. Most importantly the lights cut out intermittently usually when the heat is on and on longer trips. Also, most times it has happened when it has been raining and colder. Drove upwards of 40 miles with the headlights cutting out intermittently in the rain and cold, problem has continued to recur but seems to be related possibly to having the heat on. …”

“Driving on the hwy and the car started to overheat with hot steam shooting out from the engine and it also had a strong coolant smell. The car could not be driven until l it had $1,500 in repairs for a known, leaking plastic manifold issue. This failed part cracks and leaks into the hot engine area. And, ford had redesigned the failed part. Additionally, ford had once offered free fixes for a few months for police cars and taxi cabs with the same engines under a class action law suit but didn't tell the owners about. …”

“The contact owns a 1999 Mercury Grand Marquis. The contact stated that water was leaking from under the vehicle. The vehicle was taken to an independent mechanic for diagnosis where the contact was advised that the intake manifold would have to be replaced because it was fractured. The manufacturer was made aware of the failure. The vehicle was not repaired. The approximate failure mileage was 114,000.”