i went out and pulled some codes, as my truck hesitates when accelerating from a stop. it seems like its not getting enough fuel and wants to stall out for a second. then re cooperates and goes. and its annoying because sometimes it DOES stall. so i did a tuneup. plugs, wires, cap, rotor, even did coil pack, then i replaced my o2 sensor, and it still does it. i pulled 3 codes.
1. 636-o. which is transmission oil temp higher or lower then expected.
could this one be because i pulled the codes while my truck was cold? im in Michigan and its relatively cold right now.
2.629-o. which is converter clutch solenoid circuit fault or lock-up solenoid circuit fault. My truck hesitates before going into gear, drive or reverse, not when im driving, just initially when picking gear. is this code related to this?
3.542-o. which is fuel pump secondary circuit fault. which sound right because theres a bipass wire from the pump to the fuse panel under my dash, if i take the wire out the truck wont start, i think theres a short somewhere i just can't find it . could this fuel pump code be causing my hesitation at a stop??
thanks, mike

 

Ummmm.........Mike,

Are you sure you're in the correct year forum ???

Bob

 

ya, i have a 95 f150 4.9l 4x4 with e40d trans. why?

 

Your term "Coil Pack" is why.

Anyhow, the 4.9's are very dependent upon a good block ground.
The block ground is a single ground point (bolt) on the starter.

You should wire brush both the ground point on the starter AND the terminal on the negative battery cable till they're shiny and bright, then apply a dielectric type grease to both surfaces then re-install.
Clean off the negative battery post and clamp as well.

It'd be a good idea to clean the ground (as above) near the battery, on the fender as well.

See what happens after you do those things.

Bob

 

Code 636= TOT (TOT= Transmission Oil Temperature) sensor voltage out of self test range. Typically a false error if you did not warm up the engine and transmission before running the KOEO/CM tests.

Code 629= Converter clutch control circuit failure (indicate solenoid did not change state when requested by the Powertrain Control Module (PCM).

Typical causes are:
-- Damaged solenoid/assembly.

-- Open or shorted harness (internal/external).

-- Damaged PCM.

Code 542= Fuel pump circuit failure This is more than likely caused by your jumper wire.

Have you checked/replaced the fuel and air filters? Have you checked the fuel pressure?

 

whats it called then? 0.o..but i will do all those things, clean grounds and terminals, also il warm the truck up, then test it again to see if the TOT one goes away, and il check fuel pressure. then i'll get back to yall with what i find. thanks!

 

Mike, it is a good idea to put the vital info of your truck in your signature. That way we will not need to ask what truck/engine/mods you have.

Just a thought.