I have a 1996 crown vic i need to know these touble codes po305 po304

Do tune up,coils module,wires,plugs and see what happened..

Don't know, wish I did, as I am always trying to find comparable year parts. However, what I do is call the local wrecking yards and ask them on the phone. They have it on their computers.

Good luck! :)

code p0102 refers to MAF/VAF sensor ---low input ===causes --wiring short to ground. MAF/VAF sensor
code po172 refers to system too rich --bank 1=== causes ---intake blocked --EVAP canister purge valve---fuel pressure ---HO2S sensor
code po random misfires ---plugs --wiring ---injectors--low compression
code po305 refers to cylinder 5 misfire detected ===causes --engine mechanical fault--ignition/ fuel system ---injector ---ECT/MAF

I would check that the air filter is not blocked first as it affects the MAF/VAF sensors . Have a fuel pressure system pressure test done

PO300 Codes-- are cylinder misfires

PO301 thru PO308

Last # is the cylinder

Could be bad ignition coil for a cylinder
or a coil pack for that side,depending what
engine you have

#1 &#4 are at the front & back of the passenger
side of your motor or firewall side if transverse

You will need to provide details of who worked on it
& exactly what was done besides replace a coil based
on a code

Codes aren't very good with COP Ignition but a complete
coil pack on one side should take care of some issue

Vacuum Leaks & other items can cause misfires & the codes
don't tell you to replace ignition parts as you may have

No,not without a lot of switching of electronics

1993 is OBD1 & 1996 on is OBD2 System

The engine may be okey-- but not the induction
system or any electrical

The 300 codes are misfire codes, do a tune up and that should fix the problem. the 155 i will have to investigate and try to see what it is.

Did you mean PO305 for cyl #5 ?

You say boot is good
What about the coil,correct me
if I'am wrong, but you do have COP
Coils!

A PO305 doesn't alway give exact results,
if you have multiple codes but for a $60.00
coil should end the misfire.

You already know to:
Check for vacuum leaks
Clean throttle plate
Clean MAF
Replace front (2 ) O2 sensors at 100,000

No you must have a scan tool

The speed sensor in the transmission is most likely the problem.

might be the coil pack is bad, wires, plugs, o2 sensors, dirty injectors, catalic converter ( only if you smell rotten eggs ) . cylinders are misfireing.