Ford Repair: 1986 F-150 4by4 302 fuel injected, automatic overdrive transmission, haynes manuals

Question
Hi,

I have two questions and the first one has to do with engine failure to idle fast upon initial start and requires pumping of accelerator to keep running.  Once engine is warmed up it will idle roughly but has considerable hesitation when pressing down on accelerator.  Appears to run smooth after the hesitation is over but does not seem to have same power or acceleration as normal.  I tried a new air bypass valve on throttle body and it didn't help so I cleaned and put the old one back on.  I replaced the throttle position senser and it did not help.  I unhooked postive battery cable for 20 minutes but did not make any difference.  What would you try next?

Second question has to do with the automatic Overdrive transmission.  It works fine in all gears except the OD.  It shifts into overdrive early at about 35 MPH instead of 45 as it did when new if there is no load on truck and if the truck experiences a load situation after it has shifted to OD and is moving greater than 25 MPH, instead of shifting into a lower gear it will go into neutral.  If the truck has slowed to 25 MPH or less it will downshift like normal.  It will also shift into and out of OD normally if I manually shift between drive and overdrive.  Is there an adjustment that can easily be made to remedy this?  Is there a problem with driving the truck below 45 MPH in OD?  Your help would be greatly appreciated.  Thanks in advance.

Answer
Bob:

Your engine concern could be anything from wiring to a fuel pressure issue.  Transmission can be adjusted using the t/v cable that runs from the throttle body to the transmission and basically acts as a kickdown.  HAYNES manuals normally list an adjustment procedure for setting T/V.  Hope this helps.

Patrick