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Flashing engine light(CEL) means active misfires so engine damage can occur

Steady CEL means codes are set in memory
Get the codes an WRITE THEM DOWN!!!!!!!

Unfortunately, 2004 to 2006 Ford Rangers with 3.0l engine have a TSB about what you are seeing
TSB seen here: https://www.ford-trucks.com/forums/8...placement.html

Hopefully this is NOT the problem, but I would get compression test done to eliminate it FIRST .
Otherwise you will be wasting money and time on non-fixes

When was the last time you filled up the tank?
"Bad gas", gas with too much water in it, can have the same symptoms, idles OK but misfires under load

 

 

How many miles on the engine? Also let us know the engine codes as that will help.

I had this happen to me about 18 months ago. The spark plugs had about 20k on them but they were standard plugs. I replaced the plugs and still had the miss. I replaced the plug wires and still had the miss. I replaced the ignition coil and it ran smooth once again.

About 5 months latter it started doing it again. I changed out the plugs - no joy and the same for the wires. The ignition coil I had gotten had a lifetime warranty. I swapped it out and it worked for two weeks and died again. I am on my third replacement and it has lasted a year.

 

If you have a 'Smartphone', a phone that can run APPs, then you can get a Bluetooth OBD2 reader for $25-$40, download Free APP and you can read codes on your phone, and also watch LIVE engine data, which can be helpful.

The Bluetooth OBD2 reader works on ANY vehicle sold in the US or Canada since 1996, ANY VEHICLE, that's the LAW, not a Ford thing or even a Made in the USA thing
So not a bad investment if you plan on owning vehicles sold after 1996.
Rent it to friends for $10 and make some money back, lol.
I would get an extension wire, $5, with it, some OBD ports are recessed in the dash so you have to remove a panel to plug in the Bluetooth unit, with extension wire you do not.

We do not know whats wrong with your Ranger??
So "safe to drive" is relative, if fuel pump is going out then it could just stop and strand you.
Will engine be damaged, usually not with your described symptoms, but back off the gas pedal if CEL starts to Flash again

 

I have an 04 3.0 with a miss-fire at idle, it starts off as just a slight shake/miss and progresses until the CEL begins flashing and the truck shakes rather hard. It threw two codes in the low p300s for cylinder 2 miss-fire detected, and another for miss-fire within the first 1000(?) revolutions. The previous owner had documentation to get plug wires done, and the ones there look new. I believe the plugs were replaced with the wires but I'm not sure. So, I pulled the cylinder 2 plug, the gap was .048 inches and it had a few white spots on the plug. I threw the plug back in and twisted the plug wire connections back and forth to try and eliminate a bad connection. During the test drive after putting the plug back in, I cleared the codes and then checked them again once the CEL came back on. The two codes reported were the same cylinder 2 miss-fire code, and a random miss-fire detected on all cylinders code. Given this information, how likely do you think my cylinder heads are bunk, and how much would it cost to get new ones installed?

Edit: mileage just turned 116.5k miles

 

I too would like a answer for this I think I have the same problem 😔