Bignition modual gap spec - Troy Bilt Backpack Blower, 25cc, 160 Mph, 500 Cfm, Model No. Tb25bp

When you buy plugs that fit your car, they are gapped to specs, but you should always check the gap anyway.

The spark plug gap should be shown on the Vehicle Emission Control Information (VECI) label, under the hood or on the radiator support, the long white label or sticker.

i think you left out the word NOT? above.
I'm not boring the cylinders, right>? key word NOT.
if not tapered the gaps are spec,.
if bored , the same.
if not bored, the answer is below. in all cases.

that is easy, the bottom of the cylinder is not tapered.
you measure and set ring gap there (BTC), and it is set (ground) right there..
and then move it to the top and see it go larger ?.that gap. it sure will.
or do the math and add the taper measured amount to the gap spec. (using equation, Pi x D. = circumstance) (D = tapered max diameter)
what you don't want is , to have the gap hit zero as the piston
goes to BDC.

so say the taper is .005"
so circum is .016 wider, add that to spec gap.
then slide ring to BTC see gap go to, spec.

Pi = ? = 3.14"

Engine light will stay on until the engine starts. Its a self test of the system. As far as it not starting it sounds like the ignition modual in the distributor has gone bad. (common in 90's) Also the control modual on the drivers side fenderwell is also known to burn out. Both control spark.

Check on the VECI label under the hood, vehicle emission control information, the long rectangular label. It shows tune-up specs and spark plug gaps. And yes, halphin, the wrong gap can cause a misfire, if too far off.

intermittent spark usually caused by failing ignition module in distributor cap, but first check air gap on pick up coil--should be 0.008-0.016 in. (0.2-0.4 mm). If air gap is good, replace module. If air gap is bad, adjust and see if problem resolves.

the only thing you can adjust is spark plug gap. the others are computer controlled. the gap can be found on the emission sticker, located in the engine compartment on the underside of the hood or on the fan shroud. possibly on the shock mount tower.

use business card to set air gap

Check the gap on your spark plugs, if not to spec - replace them and gap them top specs. The spec is on your sticker in the engine compartment.

Well I can't really help with the timing specs but the points gap should be .019 (in.), but I always learned to use a match box to gap them  and that works great too. Hope this helps.

go to autozone.com

click on repair guide, then on specs, it tells you the gap in the specs.