96 firebird 3800 v6 multiple misfire

Firebird 3.8L, vin K, firing order shows to be 165432.
How long since a tune-up? Any applicable trouble codes? Check and clean idle air system.

i would change plugs and wires change one at a time. i would also test the coil pack. may want to do that first.
http://easyautodiagnostics.com/gm/3.1L-3.4L/ignition-coil-pack-tests-1

Check all vacuum lines for leaks. Check spark plug wires for and spark plugs that may be worn and causing idle misfire.also check the fuel pressure regulator. any codes?

Do a Cylinder Leak Down Test --to see if the valve are shot & leaking

You can also do an electronic cylinder contribution test

Then if the all seal, check the timing belt

After that check for vacuum leaks with evap smoke machine

What is the firing order on a 1997 Pontiac Firebird 3.8 V6?
165432 -- left side is odd numbers, right side is even numbers


Charlie

P0101 is the MAF sensor and if it has even a tiny amountof crud on it, it can keep the dar from running. clean with ELECTRONICS cleaner not carb/brake spray.

P0300 is multiple misfire detected. Sound like it might need tune-up parts

P0420 is the catalyst system bank 1 low efficiency.

I would start with changing the plugs, wires, cap and rotor. And clean the MAF sensor with the proper cleaner. Then see if the car starts and idles. If it does then clear the codes. If it doesn't run right then I would suspect the MAF sensor is kaput. The P0420 code can be caused by a poorly running engine.

Hello smileynv: My name is Roger and I will answer for you.The 1988 Pontiac Firebird had a 2.8 v-6 engine. The timing set at 10 degrees in drive. The 1989 pontiac Firebird has both the 2.8 and a 3.8 engine.The 3.8 engine a DIS (direct ignition system) Had no distributor. The timing was preset and controlled by the computer system. There was no way to adjust the timing. Please rate the answer. This way I know it was useful. Should you need further help please just ask. Thank You for using Fix Ya. Roger

For the 2000 Chevrolet Impala 3.8L V6:

Firing Order:
1-6-5-4-3-2

Cylinders:
.....(back).....
|...2...4...6...|
___________
|...1...3...5...|
.....(front)

Ignition Coil Connections:
(back)
o <---6
___
o <---3
o <---2
___
o <---5
o <---4
___
o <---1
(front)

Let me know if this helped, or if you have additional information or questions. Feel free to contact me at FixYa.com!

sounds like spark plugs or spark plug cables are bad and it is in fact misfiring this happened to me in my car and my spark plug cables were bad

Sounds like a fuel problem, when was the last time the fuel filter was chg.? If that is not an issue, than a fuel pressure test is in order, It should have around 48 to 50 p.s.i.