So it started with the EGR valve code p1406 and p0300 random misfire. I ran the codes later that day it was p1406 (EGR valve) and p0305 (cyl 5 misfire)
I've changed the wires and plugs and checked the coils. I attempted to listen to the fuel injector but couldn't because of how far back it is and my screwdriver isn't very long. Today after changing the sparkplug wires the car was very sluggish and started backfiring, but only when increasing pressure on the gas pedal it doesn't backfire whilst idling.The only four things I can come up with is a bad fuel injector, clogged catalytic converter, bad O2 sensor, or a faulty valve on cylinder 5. Please dear God someone help

 

welcome to the forum, moved thread to 4th gen general section for you. double triple check that plug wires are in the right place.

 

Thank you for that I checked the rules that's my fault. I checked my wires I've even gone off the diagram from the manual of a 96 v6. Probably need to check em again tho can't hurt nothing

 

have you pulled the egr to see if it needs cleaning or replaced?

 

also if you dont have a factory service manual you can download it here, 1996svcman http://www.mediafire.com/?40mfgeoe4ctti there are a couple different ways a gm 3.8 in 96 is wired. best I could tell there's the Camaro and all the rest.

 

Yeah I went ahead and replaced the EGR when I saw the code. Very much appreciate the manual I've been looking for one but have yet to be able to find one for a 97.

 

for the life of me I can't remember is the 98 or the 96 applies to the 97, I think some is 98.

 

Is there any noise coming from the valve train? No exhaust code makes it hard to put it on the catalytic converter. Injector seems more likely?

 

Man cylinder 5 is a bear to work on.

Its not a pugged cat, That would be low power not a miss, Its not the o2. o2 can cause random misfires but not specific cylinder misfires.

A broken vacuum line could cause both codes but only if the vacuum source is pulling from the cylinder 5 runner.. Did replacing the EGR valve fix that code (you would have to clear the code and see if it reset

The question is do you want to do a compression test or swap an injector with another cylinder.

There is no reason an engine should run worst after new wires. Sound either a wire is not on all the way or the plug wires was not made right or the wires got crossed,