Spark plug gap for my 2001 ford ranger 6 cyl. 3.0 motorcraft platinum sp-432

There is a little controversy about this. Searching the web, the best explanation I see is:

he 0.061-0.068 gap comes from the Ford OEM Service DVDs for 2003, 04 & 05, for the 4.0L Explorer, Explorer Sport-Trac, Mountaineer & Ranger, originally equipped with the Motorcraft AGSF22PM plug. Interestingly, in 2005, the Mustang started using the same 4.0L engine. In that application, the engine was equipped with the AGSF24N plug (a hotter plug). The gap on the DVD is shown as 0.052-0.056 in.

Through 2002, all 4.0L SOHC plugs, according to the Ford DVDs, are gapped at 0.052-0.056, using AGSF22PP plugs as replacement plugs.

The 4.0L SOHC is a waste spark engine, which uses slightly different plugs on the left & right banks.

Replacement plugs are usually double platinum, suffixed PP so they can be
used on both banks.

On the 2006 and later Ford DVDs, all 4.0L SOHC plugs are gapped at
0.052-0.056 in.

On the Ford OEM parts site, the AGSF22PM plug isn't listed. The replacement
plug for 2003-05 4.0L engines is the SP400, which is shown as having a gap
of 0.052-0.056 in.

The sites for Autolite, Champion and Bosch all list replacement plugs, for
those years as having a gap of 0.054 in.

Bottom line, it looks like the original plugs in the 2003-05 engines, except
for the 2005 Mustang, were gapped at 0.061-0.068 in. Replacement plugs,
regardless of manufacturer, are gapped at 0.052-0.056 (0.054), regardless of
electrode type (iron, copper, platinum, double platinum, or iridium.

1.10 mm

Hi
original spark plugs ( MOTORCRAFT AGPS22PP1 1.0mm gap
you can use ( CHAMPION RC8PCY 0.8mm gap
or ( NGK PFR6B-II 1.1mm gap
Note that the specs given are for euro ford 2.3 engine code E5FA

Good luck

0.042-0.046 is the correct gap for your spark plugs,If it is backfiring now and was not before make sure you were not sold platinum bosch plugs and if you are using factory plugs,then I be looking for a faulty spark plug.Also make sure the firing order is correct.

3.0 L V6 engine - .044 inch 4.0 L SOHC V6 engine - .065 inch ( 2001 to 2004 Ranger )
According to motorcraft.com

"Front" indicates front of the vehicle

Motorcraft Spark Plug Part Number MISP479

Part#: MISP479
Part#: MISP479 Part#: MISP479 Description: List Price: $5.52 Our Price: $4.68 You Save: $0.84 Quantity: MOTORCRAFT SUPPRESSOR SPARK PLUG, PLATINUM IRIDIUM, SOLD INDIVIDUALLY -- 0.054 in. gap size, standard service plug; Delivers maximum voltage to the spark plug while maximizing performance and increases engine life; Resists corrosion and abrasion; Reduces the chance of misfire.

Depending on the mileage, the excessive gap may be due to wear. It also may be from the plugs not being properly gapped when they were previously installed. I would recommend installing a new set of plugs, and setting the gap to the factory specs.

MOTORCRAFT Part # SP420 {#BSF42C, BSF42CF4}
.044" Gap
this gap has been he same for years, who told u 0.26"?

Have you tired the Idle Air Control Valve? When was the last time you did a tune-up with new Spark Plugs and spark plug wires? Make sure you use Motorcraft Platinum spark plugs if you want the best performance for your vehicle.