intermittent FIPL/TPS issue

[fuglyf350]

Howdy,
I've been lurking for a bit and just happen to be stumped with an issue my truck is having.

I have a 1994 F350 7.3l factory turbo truck,
has 150,000 miles

I've recently installed all new battery cables, batteries, starter, glow plugs, new fuel injector lines and fittings, flushed the trans and all fresh fluid, trans filter.

Anyways, I replaced the FIPL or TPS with a napa unit roughly 5-6 months ago, at the time I didnt bother setting it I just swapped it out with the original one and was good to go.

I pulled a 7,000 lb trailer a little over 1000 miles with out any issues.
Then while driving unloaded, about an hour away from home 30% city 70%highway rural driving it seems to hesitate on the 1-2 shift and then the OD Light began to blink.

The truck still went through all the gears just shifted rather ******* the 1-2 and occassionaly in the higher gears.

So I pulled out my multimeter and set the tps to .99 Volt at idle ( I later bumped it up to 1.3volts)

The volt-meter gradually increases without any spikes or drop in voltage as the throttle is depressed.

Now what I have noticed is that If I am accelerating and quickly release the gas pedal it will ocasionaly go back to hard shifting and the blinking O/d light comes back on.

so now what I have noticed is that if I quickly apply and release the accelerator my tps reading drops to .4 volts or less before returning to a steady 1.3volts

Is the momentary drop in tps voltage enough to make my O/D light begin flashing and make my shifts much firmer ???


thanks!

 

[fuglyf350]

bump, no one has any idea ?

 

[icanfixall]

That is a difficult problem. I never have seen it before. You could clean the 6 or 7 electrical connections for the trans. You have 3 under the master cylinder and the rest down on the trans. Several are on the trans tailshaft and one is behind the heat deflector plate on the muffler side of the trans. Clean them with contact cleaner that wont harm plastic. Let dry and grease them with plenty of die electric grease. It has helped others. The fittings get a white corrosion in them and causes all kinds of trans trouble. Figure this job will take about 2 hours and most of the work is overhead so be careful. The cleaner tastes terrible....