my car runs fine in park, when you put it in gear it stalls out. What could the problem be.
HOT or COLD...both times?
usually happens when the engine warms up. After it has running for awhile.
you DO know this could be MANY things as now is a guessing game...you could get a cheap handheld scanner stick it into your OBD-II port (not three feet from the ignition) and read what is up with your system...if it's a bad TPS...it will know...tho should have issued a CEL...some problems do not~
one not so pricey process of elimination would be to replace each and every butyl-rubber black (coaltar-and chewing gum) cracked and bloated lines with silicone ones...bout ten times more expensive, but will last forever and not crack bloat or leak and remain flexible as a silicone implant~ be methodical...replace them one at a time...summitracing offers them in various colors too~
sounds like probably maybe a Intake Air Temperature sensor...as this might make the thing run rich, black and chokey...did you witness the sight and smell of the exhaust?....was it running black?~~ https://www.google.com/#q=1999+Mercury+Grand+Marquis+air+intake+tem p+sensor
I have had it hooked up, the only thing I am told is that it could be a bad o2 sensor. Another person told me that its my coils.
see, it's tellin' the computer there is COLD air in the intake plenum...makes the combustion RICH and fouls the plugs~.....just a guess...don't call your lawyer right away~
the 02 sensor would toss up a check engine light CEL, right away...do not collect $200, coils....being individual coil packs would idle humpty- dumpty~and not have any power~.....so nay on the ignition theory~ sorry~
...and would store a trouble code with that as well....get a fifteen dollar scanner or bring it to an 0'mallory's for a free scan~
...also the 02 sensor failure would make it run POOPY and black horrible exhaust as well~
the intake air temperature sensor is situated on the intake plenum...most easy to replace....and cheeeep too~
...another consideration is the Throttle Position Sensor or tps...99,,,,WORN...these will make the throttle behave properly~ https://www.google.com/#q=1999+Mercury+Grand+Marquis+TPS
I'm having the same issue and i have a hunch its the transponder chip in the key, she runs like a dream and then dies out and sometimes wont start up for 10 minutes, getting gas and all the coils and plugs are new, also could be dirty air sensor or cps
Its possible its the torque converter or vacuum actuator on transmission or possibly crack or broken vacuum line
WOW, I have the same model and type car and the same thing has been happening to me. Not everyday and only when its really cold. Could this be a manufacturer defect of this car?
My Mom is having the same problem with her 2002 Mercury Marquis. The car cranks but as soon as she puts it in gear, the engine goes dead. The check engine light also comes on. Happened twice last year. She is older and had to have car towed twice. Today she called me and it happened again, almost a year later. Got the car towed home. 2 hours later went out and the car cranked and went into gear and drove fine. Any help would be appreciated.
I have a 1997 Dodge Neon That is startind and then put it in drive it will die
My car (2002 grand marquis) does the same thing. When it's cold out, start it up, put it gear (drive or reverse) and it will stall. This will happen until it warms up a bit more. Also, driving down the road while it's snowing it will have misfires. I changed the I take temperature sensor and it didn't fix it. I changed the throttle position sensor as well and that didn't fix it. My next change is likely the mass airflow sensor.
I have a 1984 mercury grand marquis that does the same thing but not black smoke what should I do but at a low coast
My 2003 Ford focus does the same thing
i have a 93 chevy lumina it run fine in p,r,n when i put it in drive it stall and die what can be the problem
My 2001 Gran prix does the same thing. When i put t into gear it dies. i put a new throttle body sensor in it, cleaned out the throttle body, and checked the coils. Still does it .backed it out of the garage just fine. as soon as i put it in drive, it died. then it started fine, put it in drive, then died again. Step on the gas and it revs fine. Im thinking that the main problem is valves. When a car is idling, it runs bc the valves dont have to move as fast. but when you put it in drive or gear they do and they are sticking. So replace your valves and they will run fine.
A fast easy and cheap thing to try is a new fuel filter I had this problem of stalling in gear and had a po171 code to lean every forum I looked at called for checking sensors and for vac leaks and the entire time it was nothing but a clogged fuel filter put on a new one and it runs great.
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