Misfire only in drive when idle. Ok when driving

run the fault codes and check for random misfires on one or multiple cylinders
try using injector cleaner in a couple of tanks of fuel

Idle adjustment procedure - Ford Explorer and Ranger Forums ...

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Mar 25, 2015 - 19 posts - ‎11 authors Idle adjustment procedure Under the Hood. ... Below are the stock idle speeds (RPM) for my 2000 SOHC V6 with strategy CDE4. ..... when you apply the throttle or it could be too much base timing causing a huge misfire. High Idle Blues 1994 4.0
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Could be a bad cam or crank sensor. But before you go to electronics, ck the plugs, wires & coil or coils (whichever coil system you have) Start with the plugs

When you know the symptom who needs codes?And if there was a code it probable say lean bank 02. why simple you have a misfire. the smell rich exhaust the shake and sputter in drive. 2 causes the Expedition suffer from ,An open EGR valve.If you can change a fuel filter and change a spark plug you can test this. when the engine is running and misfire at idle and the vehicle is warmed up and at operating temperature. Turn off engine. Go to the EGR is it hot to touch. because if it is it open and this the the culprit.Another misfrie is from COP (coil on plug.)When you change the spark plug where any of the spark boot torn or worn that spark can go through. Or even a faulty COP will do this .To find it you have the engine running and lift one COP out of the cylinder and listen for a engine drop if the engine RPM drop the COP is good if no change in engine the COP is bad. By the way 600rpm in drive is low

Its either a faulty idle air control valve or a faulty fuel pressure regulator.My bet would be the idle air control valve. If you pull the vacuum hose off the fuel regulator or the map sensor and fuel runs out then the regulator is bad.If you replace the control valve then you have to reset the computer.

Cylinders are numbered from front to rear (grille to firewall) passenger side: 1-2-3, driver's side: 4-5-6. Firing order is 1-4-2-5-3-6
Did you check by pulling #2 out while the engine is in idle to see no weakness from the engine? BTW your coil pack cost $80.

EGR valve, throttle position sensor or idle air valve should all be checked

idle air contol valve is bad

Sounds like a bad IAC (idle air control valve/sensor) that controls your idle when going from throttle to idle. If bad your idle will act crazy and can cause stalls easily. Pretty sure that's it.

po301 thru po306 all misfire codes cylinder 1-6 remove plugs and replace them..... set the plug gap first
i suggest u replace the wires also if they never been replaced all these misfire codes can set the others and one is for the oxygen sensor ( 02s or HO2S) CIRCUT MALFUNCTION do u know how to check wireing systems
do the tune up plugs (set gap) .052-.056 change the fuel filter also. clear the codes hows it run
this info is for 98 E-250 4.2Litre
what engine do u have 4.2L or 4.6L i know it is a v-6 by the codes