F150 misfire at shift point, and above 45mph

Parked behind the barn for a year, just purchased this 1993 F150, 300CID
I6, 5 speed manual, 2 WHD, long bed, XL package, with dual tanks.
105,814 miles.

Rebuilt Engine and new clutch in 2004. Minor body damage on right side,
with passenger side mirror whacked off, and front bumper bent down two
inches on Drivers side, cross brace on bottom under Radiator is pulled
down like it was yanked out of a bog by a chain.

Lady said her dumb ephew rewired the turn and brake lights, after the
original harness burned out after U-Haul trailer rental in 2006.

On both tanks, with 6 gallons of new gas in each, last night, when I
bought it for $400.00, and drove it about 14 miles to home, it would
stumble as the engine reached it's shift point in each gear.

So, I'll be checking the codes, with my OBD Code tester, and then,
changing out an fuel filters, and, yes, the gallon left in each tank
before I pumped in new gasoline did stink from the solvents venting off.

Tank switch works, transfers while in motion. no change of symptoms on
either fuel tank.

Suggestions of things to test, replace? Dirty injectors, plugs, fuel
filter? Will be doing a tune up, etc. Definitely will disconnect and
re-learn the engine control computer...

I'll be 62 in a month, was a medium and light duty mechanic, and
computer technician, in the US Air Force, for 20 years, until retirement
from the USAF, in 1985.

I have owned and operated a couple auto dealerships with attached
service garage, where I was the the mechanic, with a helper and have
repaired hundreds of vehicles.

I've solved some very difficult auto, motorcycle, aircraft, boat, and
truck problems. So, this should be something I can solve, but, I have
always mentored with the wise mechanical technicians that I could find
available.

monitoring this group shows me that such wise and experienced folk are
still extant.

TIA for your ideas and suggestions.

Sounds like a weak coil, wet or poor spark plug wires etc...

patrick wrote:

> Parked behind the barn for a year, just purchased this 1993 F150, 300CID
> I6, 5 speed manual, 2 WHD, long bed, XL package, with dual tanks.
> 105,814 miles.
>
> Rebuilt Engine and new clutch in 2004. Minor body damage on right side,
> with passenger side mirror whacked off, and front bumper bent down two
> inches on Drivers side, cross brace on bottom under Radiator is pulled
> down like it was yanked out of a bog by a chain.
>
> Lady said her dumb ephew rewired the turn and brake lights, after the
> original harness burned out after U-Haul trailer rental in 2006.
>
> On both tanks, with 6 gallons of new gas in each, last night, when I
> bought it for $400.00, and drove it about 14 miles to home, it would
> stumble as the engine reached it's shift point in each gear.
>
> So, I'll be checking the codes, with my OBD Code tester, and then,
> changing out an fuel filters, and, yes, the gallon left in each tank
> before I pumped in new gasoline did stink from the solvents venting off.
>
> Tank switch works, transfers while in motion. no change of symptoms on
> either fuel tank.
>
> Suggestions of things to test, replace? Dirty injectors, plugs, fuel
> filter? Will be doing a tune up, etc. Definitely will disconnect and
> re-learn the engine control computer...
>
> I'll be 62 in a month, was a medium and light duty mechanic, and
> computer technician, in the US Air Force, for 20 years, until retirement
> from the USAF, in 1985.
>
> I have owned and operated a couple auto dealerships with attached
> service garage, where I was the the mechanic, with a helper and have
> repaired hundreds of vehicles.
>
> I've solved some very difficult auto, motorcycle, aircraft, boat, and
> truck problems. So, this should be something I can solve, but, I have
> always mentored with the wise mechanical technicians that I could find
> available.
>
> monitoring this group shows me that such wise and experienced folk are
> still extant.
>
> TIA for your ideas and suggestions.