The idle is going up and down when the vehicle is not moving at red lights or in traffic and it sounds like its misfireing or something? basically the engine is running rough when its at a low idle but it drives fine untill yesterday when it all of a sudden stalled on the highway thank god i made it home. the truck still starts but something is not right cause it keeps stalling. it definitely seems like a fuel problem.

AC has nothing to misfires or o2 sensors.

Start with the basics.

Check the spark plugs, or perhaps just replace them all. Or you can test, put plug 5 in plug 1 swap. Does the misfire move? If it does, the plug is the issue, if it doesn't is is the coil pack to it.

Clean throttle body and MAF.

Clean EGR

Run car for a week, and if it is still running rich, change the sensors.

OR, just go to an auto-electrician with a $5,000 scan tool computer although with a 1999, the data will be fairly basic but will diagnose.

https://www.google.com/search?q=1999+Lincoln+Town+Car+shakes+at+idle.+Cylinder+5+misfire+and+bank+1+and+2+too+rich

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Red light means Stop, so it shouldn't have to go.
However, if the red light were defective and/or requiring traffic marshals to wave motorists through the intersection, then perhaps you should check up on the following:
1. Has the car switched off?
2. Is the idle (rev count) high enough to move the vehicle from a stopped state?
3. Is your hand/foot brake still engaged?
4. Is the vehicle in the correct gear (the typical gear to be in based on your gearbox type, may be 1, D or D1 ..for forward motion of the vehicle)
5. Is the clutch(if present) still pushed in? (this will prevent the selected gear from turning the engine)
6. If no clutch is present, you have an automatic transmission.. do you have enough transmission fluid?
If all of the above are in order, it might be that the gear you wish to use is faulty or borken, or your clutch plate is worn down too much (this can happen when you 'ride the clutch' a lot.. both will require attention which I can not talk you through via this medium. An auto shop should be consulted for further advice..

sounds liek your crankshaft postion sensor but to be sure i would replace spark plugs and wires and change the oil if you havent recenly and check your air filter if its to dirty the car will stall

May be a coil pack if you say it starts when it gets warm..But check make sure the plugs and wires are good as well..If the engine light is flashing,,you need to have it fix as soon as possible..When its flashing ,,that means that its doing damage to the catalytic converter..If you wait to long you will have to replace that as well...they are very expensive..

Chances are one of your exhaust pipes is hitting something or a shield is loose. Easy to check, just try and move the exhaust system and see if it contacts anything, then start it up and track the noise to it's source. DON'T touch the pipes when it's running or has just been running. THEY ARE VERY HOT!!

Does it gallop when you are sitting idle and the RMP gauge bounce up and down between 1000 and 1500? If so, clean the throttle body and see if that solves the problem. I had a similar problem with my 03 Yukon XL (same truck) and cleaning the throttle body fixed it.

It sounds like there may be a cylinder misfire... .basically a misfire is when a cylinder does not fire correctly, This can be caused by faulty spark plugs,coil packs,dirty fuel injectors,clogged fuel filter,or bad cylinder compression. When was the last time you gave it a tune-up? I would lean towards changing the spark plugs myself. good luck

When it dies and wont restart, check what is missing-- spark or fuel

Sounds like your belt to the generator or alternator is slipping on acceleration.Turn off eng an ck tension by moving belt up and down at point between alt and pully. should not move more than 1 inch. The other lites may be due to low battery level.

hi, the valve springs are bad in this vehicle. this is causing the misfire. this is quite hard for the CPU to pick up. normally, the cam sensor will at times.