Misfires it has a bad miss when running, service engine light is on, trac off light is on.

number 4 misfire check either plug or coil --as to jerking if vehicle is not running correct [misfire ]it will not drive smooth trac light --it can be related to the misfire or check abs and brakes and power braking will set off traction control and puts a strain on brakes and c/v axles

Go to an auto parts store and have them scan for a code. That should give you an indication of what is wrong with it.

misfire, has many cause, i have 50 reason list. for get that.
1: bad engine compression, or other major engine issues. mech.
2:bad spark
3: bad fueling. (too much or too little)

it only takes a few tests to find which it is, and in that order.
above assumes, 13.3 to 14.7v at the EFI system at all times running.
and EGR is not leaking.
what does engine light mean.
are you saying the CEL , check (service) engine light glows running? if yes ? why not scan it and report all DTC codes present. P0300 is random misfire. and P0301 is #1 cyl misfire.
as 2 examples.

Misfire condition on cylinder 5 (P0305) and cylinder 8 (P0308). There is a good explanation of it here :
http://troubleshootmyvehicle.com/ford/4.6L-5.4L/how-to-diagnose-misfire-codes-1

Sounds like ignition problem - I would first check the plug wires carefully for cracks, routing problem (flashing to engine), and incorrect order, and if all OK then check the plugs for contamination/incorrect gapping.

For engine misfiring problem check the help links mentioned below. Click the link below to go through the troubleshooting procedure :---- Engine misses and truck jumps? Hard to down shift? Issue with high gear only? http://technoanswers.blogspot.in/2012/02/engine-miss-and-truck-jumps-hard-to.html

-----------
Bad miss at idle?

http://technoanswers.blogspot.com/2012/01/bad-miss-at-idle.html

-----------
While stop engine idles like cylinder missing?

http://schematicsdiagram.blogspot.com/2012/01/while-stop-engine-idles-like-cylinder.html

------------
Engine Misfire codes for car?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html
Engine Misfire codes?

http://schematicsdiagram.blogspot.com/2011/12/engine-misfire-codes-on-chevrolet.html

--------------
Misfire on cylinder 4?

http://schematicsdiagram.blogspot.com/2011/12/misfire-on-cylinder-4.html

-----------
Oil on spark plugs and car misfires?

http://technoanswers.blogspot.in/2012/02/oil-on-spark-plugs-and-car-misfires.html

----------

This will help.

Thanks.

YOU HAVE CYLINDER MISFIRE CAUSED BY BAD SPARK PLUGS AND WIRES, CLOGGED FAULTY FUEL INJECTORS WILL CAUSE SEVERE ENGINE MISFIRE WHICH WILL CAUSE CHECK ENGINE LIGHT TO TURN ON..

This may be totally off base but my 2002 Lesabre with the 3.8 litre engine was running like this and it was the ignition control module. It is under the coil packs. The engine would start ok and idle ok but run like heck when trying to drive it. Are you getting any codes? Mine was random misfiring. The ignition module was about $150 and relatively easy to replace. Make sure everything is clean when it goes back together.

I don't know why the abs and trac off lights are going on and off unless there is a short somewhere.

hope that helps. if not repost your problem.

This is common, when ever the computer sees a fault it will turn the light on and shut down the trac, the trac cant operate correctly when engine is not running good, you will need to have the computer scanned for codes, whenever the engine light comes on the computer stores a code with the problem, a flashing light means it needs attention asap, this mean its misfiring like a bad plug or sparkplug wire, the flashing is because you can cause damage to converter in the exhaust system, many autopart stores will scan the codes for free, for example they may pull a code that says po301 cylinder 1 misfire, this would mean cylinder 1 is misfiring, this take about 5 min, to get the codes, they use a small hand held scanner that plug in inside the car under the dash to the diagnostic connector which comunicates with the computer, hope this is helpful.

A misfire on this type of vehicle can be due to 2 factors if it missing spark it will trigger a misfire code and it you have a bad INJECTOR. Most misfires are due to missing spark but there are quite a few in my experience that were due to bad injectors or bad injector wiring. To check this you need a NOID light disconnect injector wire on suspected cylinder in your case #1 and connect wire to NOID light (engine must be running for this) Your NOID light should have a consistent flickering light going while vehicle runs at idle. If light its NOT flickering at a steady pace and flickers erratically. THE PROBLEM IS A BAD Injector wiring or a bad computer. If light flickers consistently and in a steady pattern then YOU HAVE A BAD INJECTOR. Replace injector and that will solve this problem. I know this is a lot of info but It will help you alot. Good luck and thanks for using FIX YA