The throttle position sensor (TPS) may fail. Common symptoms of a defective TPS can be rough idle, hard starting, hesitation on acceleration, poor fuel economy, and stalling.
Car Problem Reports
Mercury Grand Marquis Throttle Position Sensors May Fail and Cause Engine Performance Problems
Mercury Grand Marquis Problem
Average Mileage: 113,375 mi (65,000 mi - 175,000 mi)
Visitor, 1999 Mercury Grand Marquis, 160,000 mi
going down the road and car just quit running and will not start
my 2006 grand marquis mercury stalls. It will stall while sitting still, cruising on the enterstate and everywhere in between.the only thing consistent about the problem is that , I can traveled as much as 350 miles without A problems , then all of A sudden allthe dash lites come on and the car is power less. the dealership has changed A throttle body ($700+) the car stalled going home! Please, I need your inputs .
Visitor, 2006 Mercury Grand Marquis, 65,000 mi
Car will cut off going down the road, and it will start right back up, replaced fuel filter and went almost 800
miles and it did it again. The other day it cut off sitting in traffic, but it always cranks back up??
Visitor, 1990 Mercury Grand Marquis
my car has trouble getting into 1st gear
Visitor, 1990 Mercury Grand Marquis, 68,000 mi
did a full tune up weeks ago to mee it acts like a plug not firing i was thinking maybe egr or tps might be bad,,rough idle chugs down the road
Visitor, 1999 Mercury Grand Marquis
car idles rough and stalls while running wont turn on for awhile then starts few minuts later
Visitor, 1999 Mercury Grand Marquis, 155,000 mi
itake maniflod blew i replaced it and new plugs. car ran fine for one day engine light came on and runs very rough. still not fixed
Visitor, 2006 Mercury Grand Marquis, 125,000 mi
Idle problems, stalling, warmup problems, would have replaced idle air control valve if the car had one.
Of course, with its fly by wire throttle, it does not. Replaced tps sensor after testing and inspection upon removal. Old sensor was wollered out. Important note- machine screws that attach sensor are lock tighted on and require some heat to remove without snapping off. Heat gun works fine.
have stall in engine