Misfire causing back fire turn over but no start what could be the problem?

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.

run the fault codes as misfire can be from injectors , low fuel pressure and ignition problems
all temp gauges will show a rise on stopping an engine as there is still residual heat in the block and heads with no water circulation and cooling
the fire from the exhaust indicates an exhaust valve is not closing properly so a compression test would be in order to check for valve problems or hydraulic follower problems

DO NOT ATTEMPT TO START IT IT COULD CAUSE SERIOUS DAMAGE IF SOMETHING INTERMAL HAS FAILED.Get a mechanic to take a look at it and track down the issue.Do not put in gear or attempt to start it. You said it had a slight misfire just before failing. Misfire is usually attributable to bad fuel / air mixture but does not usually result in a breakdown immediately upon happening. It sounds like something might have failed.
Good Luck

Please let me know what happens, it sounds a little out of the ordinary

You have a misfire due to bad spark plugs, ignition coil, which causes the cat. converter to melt inside

misfire is bad timing
check cam time.
check spark timing.
bad timing causes backfiring..

did you put the spark wires back like you found them or better the correct firing order? if not it backfires.
last is lean backfire.

saturn had a lot of problems with the coil posts getting rusty that will cause the misfire on cylinder number 3 and any skip will cause the random misfire see as one coil fire two cylinders the egr sensor is built into the vavle and try stick closed from carbon build up cleaning it will only putoff replacing it if it operates at all

OK, We'll cover the Diagnostic Test Codes (DTCs), starting with the standard definition set by SAE J2012 (Revised December 2007)
DTC P0171 "System Too Lean Bank 1"
DTC P0174 "System Too Lean Bank 2"
DTC P0301 "Cylinder 1 Misfire Detected"
DTC P0305 "Cylinder 5 Misfire Detected"
DTC P0316 "Engine Misfire Detected on Startup (First 1000 Revolutions)"

The "system lean" codes are pretty much telling you that there is way too much oxygen in the exhaust. There is too much oxygen on BOTH sides of the engine, and that is why you are getting codes for bank 1 and for bank 2. Bank 1 is the side where #1 cykinder is located and Bank 2 is the opposite side.

The misfire codes are pretty self-explanatory. #1 and # 5 cylinders are misfiring. The P0316 DTC is telling you that the misfire monitor is detecting a misfire as soon as the engine starts. This tells you that it is a very severe misfire and that the engine does not have to warm up and the car does not have to be driven to detect the misfire.

A misfire can be caused by many things it can be vacuum leaks, bad spark plugs, bad ignition cables, faulty ignition coils, fouled or malfunctioning injectors or injector circuits, blown head gasket, cracked cylinder head, burnt valves, etc.. etc..

However, look at the codes you have. Then look at the firing order for your engine. 2002 Mercury Sable is only equipped with a 3.0L 2V 6-cylinder engine.
The firing order is 1-4-2-5-3-6

Now if you take the firing order and split it in half, stack the two halves on top of each other, it looks like this:
1-4-2
5-3-6

When you look at the firing order this way, you can see that cylinders 1 an 5, 4 and 3, and 2 and 6, are "PAIRED" cylinders. They are exacly opposite in the firing order. Now, the cylinder only fires every second revolution of the crankshaft. With paired cylinders, one of the cylinders in the pair will fire on the first revolution and the other cylinder will fire on the second revolution.

Looking back at your codes, please note that the cylinders that are setting the misfire codes are paired cylinders.

Now the coil pack for your ignition is actually made up of three coils. Each coil fires a set of paired cylinders. If you look at the top of the coil, it will usually be marked with the cylinder numbers that each coil tower is supposed to connect to. The coil will look just like the firing order split and stacked as above.

With all of this said, I would say that it is VERY LIKELY that your misfire codes are being caused by a defective ignition coil.

The lean codes are a little different.

These are USUALLY caused by vacuum leaks which allow too much air into the engine that is not getting measured by the Mass Airflow (MAF) sensor and causes the engine to be getting too much air and not enough fuel (running lean).

I would take a good look at all of the vacuum hoses and lines. Ford is notorious for getting holes in the rubber parts that connect the PCV tubes.

If you do not find any obvious reasons for a vacuum leak, then you may want to fix the misfire codes, reset the computer memory, and drive the vehicle to see if the lean codes come back again. The misfires COULD be the cause of the lean codes. In a perfect world, this is not supposed to happen because the misfire monitors setting codes will not allow the oxygen sensor monitors to run and set lean codes. However, I HAVE seen cylinder misfires that have caused lean codes.

I hope this helps you to figure it out. Good luck!

A BAD COOLANT TEMPERATURE SENSOR CAN CAUSE MISFIRE AND COOLANT FAN TURN ON WITH A COLD ENGINE.

misfire happens because there is still fuel not burned in the cylinder so when its pushed out its burned in exhaust tube because the heat thats why you hear these small explosions. this caused if your sparking pluge not firing well . or there is a leak in the intake valve . in your case i advice you to check your sparking plug . if this helped pls vooote

If when you changed the distributor cap you misplaced the wires in the incorrect order you could have caused a misfire. When looking at the cap the correct firing order for a 4.3 liter is 165432 going clockwise. Also if you loosened the distributor hold down bolt and turned the distributor even slightly you could cause a misfire.