2004 monte carlo ss 3.8 engine diagnostic message "cylinder 5 misfire"- will changing the spark plugs resolve this issue?

The firing order for a 2004 Oldsmobile Alero with a V6 engine is typically 1-2-3-4-5-6. Cylinder 5 would be the fifth cylinder in the firing order. A misfire in cylinder 5 could potentially cause the symptoms you described, including the car shutting off while driving and the RPM gauge behaving erratically.

When a cylinder misfires, it can disrupt the engine's smooth operation and cause a loss of power. In some cases, it can be severe enough to stall the engine while driving. The erratic behavior of the RPM gauge could also be related to this misfire.
To address the issue, you should consider the following steps:

1. Diagnose the Misfire: Confirm that the problem is indeed a misfire in cylinder 5. Use a scan tool to retrieve trouble codes and identify the specific issue causing the misfire. This could be related to ignition, fuel delivery, or other engine components.
2. Check Spark Plugs and Ignition Components: Inspect and replace the spark plugs and ignition components, such as the ignition coil and spark plug wires, if they are worn or damaged.
3. Check Fuel System: Ensure that the fuel injector for cylinder 5 is functioning correctly. It should provide the right amount of fuel to the cylinder.
4. Examine Vacuum Leaks: Vacuum leaks can also cause misfires. Check for vacuum leaks in the intake manifold or vacuum hoses.
5. Perform a Compression Test: Low compression in cylinder 5 could lead to a misfire. Perform a compression test to check the compression levels in all cylinders.
6. Consider Other Sensors: Sometimes, faulty sensors like the crankshaft position sensor or camshaft position sensor can also cause misfires. These sensors help the engine's control module determine the correct timing for fuel injection and spark.
7. Professional Diagnosis: If you're unable to identify and fix the issue on your own, it's advisable to seek the help of a qualified mechanic or technician. They can perform a comprehensive diagnostic check to pinpoint the problem accurately.

A misfire can lead to various engine performance issues and potentially dangerous situations, so it's essential to address it promptly. Ignoring a misfire can also cause damage to other engine components over time.

check / replace no 5 injector or injector control

That sounds like they're installing too hot a spark plug - they should step down about two, maybe three ranges toward a colder plug, at least for that one cylinder. If that mechanic knows what they're doing, they'll know how to select a colder plug for that car's engine.

Unless, of course, the plug isn't "blown" but is instead carbon fouling. If THAT's the case, then that cylinder is losing oil badly - whether from serious cylinder-wall wear, broken rings, or a dried-out valve stem seal.

Fuel, spark, low cylinder compression. All must be checked.

If the code is 301 it means there is no power from that cylinder. It could be a problem with the ignition, fuel injector, or something mechanical.

The three plugs in the back are a bit tricky but 2,4,6 are all back there 6 is right by the O2 sensor you might have to feel around for them but you don't need a jack or any special tools just a ratchet, small extension 5/8 SP socket slide the metal sleeve forward and yank ******* the rubber plug wires after a while they will come loose 4 it about 3 inches to the left of 6 and 2 is back behind the coolant Reservoir

P0304 is a misfire cyl 4, check the plug wire, and spark plug

The COPS (coils) may have shorted the drivers in the PCM (computer). You should get a misfire code for each cylinder misfiring though.

Slim possibility, but very expensive unless you have a service contract.
LINCOLN: 1999-2004 Navigator
2002-2003 Blackwood
2003-2005 Aviator MERCURY: 2003-2004 Marauder
ISSUE: Some 1999-2004 Navigator, 2002-2003 Blackwood, 2003-2005 Aviator, 2003-2004 Marauder and 2003-2004 Mustang vehicles built before 12/19/2004 equipped with 4.6L 4V/5.4 4V engine may exhibit a runs rough, lacks power, and engine misfire, prompted by a MIL light and DTC codes P0301, P0302, P0303, P0304, P0305, P0306, P0307, P0308, and P0316.
ACTION: Diagnose engine for engine misfire concern. If diagnostics determine an engine misfire which is characterized by leakage through exhaust valve(s), only replace the affected cylinder head(s).
SERVICE PROCEDURE FOR VEHICLES WITH RUNS ROUGH/MISFIRE CONDITION:

1. Perform relative compression check on all cylinders. If abnormal, check cylinder leakage and actual compression for "low" cylinders refer to Workshop Manual (WSM), Section 303-00.
2. If leakage/compression check indicates a valve train concern, per valve train diagnostics in WSM, Section 303-00, replace cylinder head and cam assembly, pipe plugs and timing chain tensioner, per procedure outlined in WSM, Section 303-01.
3. If cylinder leakage and compression tests are inconclusive, perform misfire diagnostic, per TSB 05-22-8. NOTE: DO NOT TRANSFER SPARK PLUGS. INSTALL NEW SPARK PLUGS IN REPLACEMENT CYLINDER HEAD AND CAM ASSEMBLY. NOTE: THE ENGINE MISFIRE CONCERN IS TYPICALLY EXHIBITED ON THE LEFT HAND CYLINDER HEAD AND RARELY ON THE RIGHT HAND CYLINDER HEAD. UNLESS CONFIRMED, THE RIGHT HAND CYLINDER HEAD SHOULD NOT BE REPLACED AS AN "EXTRA MEASURE" SERVICE PRECAUTION. NOTE: THE REPLACEMENT CYLINDER HEAD WILL NOT IMPROVE OR REDUCE ENGINE HORSEPOWER OR TORQUE ABOVE ADVERTISED LEVELS.
   

Check your firing order, could have crossed a couple wires.

make sure no fuel is down in the spark plug ports it will short out the spark