Hesitation

[blackf3504dr]

One more problem has cropped up. While climbing a grade or just accelerating it will "miss a beat", not a miss fire but as my dad would have said "a hitch in it's giddy up"... New (not rebuilt) distributor, coil, ICM, fuel pump relays and fuel pump.

[subford]

Hesitation is a bad TPS most of the time.
But I am not sure that is what you are talking about.
Not sure if you are saying the transmission gives a slip or the engine is doing it.

This could be anything from the wrong transmission filter installed to the TPS or TR sensor
Note a 2WD transmission filter in a RV with a E4OD will do this. The books are all wrong on the application for the F53 on this one. The F53 takes the 4X4 filter (FOYC3Z-7A098-BA or YC3Z-7A098-BA or FT114).

[blackf3504dr]

It's the engine, trans is operating fine. Is there a way to check the TPS ?

[subford]

The best way to check the TPS is with an analog VOM.

Put the probes between the TP wire and SIG RTN on a low scale as you are looking for a maximum of 5VDC.
Slowly open the throttle very slowly with the key on and the engine not running.
The needle should go up the scale from about 0.9VDC to 4.5VDC smoothly with no jerks in the movement.

Note that the Computer only reads three voltage levels from the TPS. They are Closed Throttle, Part Throttle and Full Throttle. When the engine is first started the Computer reads the voltage from the TPS and takes this as Closed Throttle (CT). That is why you should never touch the throttle while starting the engine. The computer will then use math to come up with Part Throttle (PT) and Full Throttle (WOT or FT).

•Closed Throttle can be anywhere between 0.6-1.0 volts
•Part Throttle is triggered @ 0.04 volts above Closed Throttle
•Full Throttle is triggered @ 2.71 volts above Closed Throttle

For some more information on the TPS go to this link:
Fuel Injection Technical Library » Throttle Position Sensor (TPS)

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[Brockx]

Originally Posted by blackf3504dr

One more problem has cropped up. While climbing a grade or just accelerating it will "miss a beat", not a miss fire but as my dad would have said "a hitch in it's giddy up"... New (not rebuilt) distributor, coil, ICM, fuel pump relays and fuel pump.

Glad to see this post, returned from a 3300 mile trip Weds. night and experienced this once a day, every day. I was searching for related posts.

90% sure it is engine related, just a twitch, jerk, hic-cough, got kind of a hard shot once in the trip. I drive mostly by foot, so I think not cruise related, but to be honest cruise had not occurred to me until just now.

[subford]

Also look for arcing spark plug wires. Could also be a valve sticking sometimes.

[blackf3504dr]

Thanks Bill, I'll see if I can borrow an analog meter, or maybe just replace the TPS and see if it makes a difference. I don't think it's the wires as they are fairly new and well separated.
Someone mentioned it could be the MAF sensor, do these old 460 use a MAF ?

[subford]

No they do not use a MAF sensor. They use a MAP sensor. The MAP sensor should be either good or bad so I do not think it would be the MAP sensor but make sure the wiring to it is OK along with the vacuum line.

If in dough it can be tested also with an old dwell/tachometer that you used with your old point systems. You can also use a frequency meter to test it.