I have a 04 infiniti G35 I power wash the engine a few days ago. It started to misfire I replaced all spark plugs and the coil packs show to be not working. After all that it's still misfiring? ??

Presumably you had to disconnect the battery, so you have to reset the security system which also includes the anti-theft engine immobilizer. Solid red light means NATS/IVIS is triggered, the ECM will still CRANK the engine but it will not open the fuel injectors or deliver spark. You may need a mobile auto locksmith to program it.

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Is your NATS/IVIS indicator LED solid red when cranking the engine? If so then yeah you probably just need to get it reprogrammed, or the RFID chip in the key failed. You can follow the troubleshooting steps in the FSM, section BL - Body/Locks/Security

https://www.nicoclub.com/infiniti-service-manuals

Videos in this link

https://www.google.com/search?q=2006+infiniti+g35+security+system+reset

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The simplest answer here is pay a good mechanic to do it!! Changing the actual plugs is not a difficult job. However! On the Infinity G35 the access to the plugs is buried underneath a lot of auxiliary parts like the air filter box and air intake pipe work. There are also a number of pipes and cables you will need to work around. Then the coil packs on each plug are bolted in place with small, short bolts that if dropped are a pain in the tailbone to retrieve!
the attached youtube link gives you an idea of what's involved. DIY 1st Gen G35 Spark Plug Replacement part 1 of 3

Bad gas with too much ethanol or water can cause a lean issue and P300 codes .

coil pack...timing or a bad plug wire or an air leak

Cold starting misfires can often be caused by either tired high tension spark plug leads or ignition coil packs. If replacing leads, then replace with a full, new set. Coils can be changed individually, but it is often the case that if one has failed, then the others aren't far behind. Some cars have individual coil packs on each spark plug. Some cars have a single pack for all plugs and some have coil packs which may control two or more plugs.

To check for a misfire (ignition failure) follow these steps:

(Cold start) (Use a pair of insulated pliers)

1) Start the vehicle

2) When the vehicle starts misfiring, disconnect plug leads or coil pack connections one at a time. If the vehicle idles even more roughly, then that plug or pack should be considered fine.
Replug each connection before disconnecting the next one. Once you disconnect a plug lead or coil pack connection and find no difference in poor engine running, then you have likely found the offending cylinder. Check the spark plug condition, lead and/or coil condition and connections on that cylinder.

3) Replace components as necessary.

the only thing left to replace would be the spark plugs -I would do all the plugs-cheers Denny

You must remove the upper intake manifold, then each spark plug has its own ignition coil, remove them and the spark plugs are down in the deep well in each of the valve covers.

This is common issue with Infiniti I30 1999-2001.

When the coil packs fail they burn up components/parts on the engine computer ECU. If the problem gets worse, you will need to replace the ECU or have it rebuilt.

Is your check engine light on?
You might also get code P0505
Technical bulletin also recommends to replace
The Idle Air Control Valve MUST be replaced prior to re-installation of the ECM, or immediate damage to the computer will occur again.

http://www.myairbags.com/product/ecu-infiniti-i30-2000-2001
Common Failures:

• No Start, Hard Start, Engine Stalls
• Rough Idle, High Idle, or Idle Up and Down
• Misfire to one or more cylinders
• No signal to the ignition coils
• Engine Trouble Codes For Idle Control Valve (IACV)
• No Communication With Computer
• Replacing IAC Does Not Fix The Problem

Hi:
It seems that your intermittent problem could be a cheap fix,and you can try a few things that might fix or eliminate the problem. Since the code pointed to the #1 cylinder misfire, You could change out your spark plugs and spark plug wires as a possible cause. If it doesn't fix it, they were 5-6 years old, and a new set isn't a bad investment. If the problem persists, then you are looking at a ignition coil, coil pack, distributor cap/ rotor,depending on your particular engine. Often if you have an ignition module failing, it will affect all cylinders misfiring, often randomly , so once you change your plugs and wires, have someone clear the check engine light, so if it comes back on ,you can check to see what the new code problem is...I hope you get a cheap fix!