Tune/computer issue

[snoboy]

A few weeks ago my CEL came on for the first time. I installed the SCT and checked for codes but none showed up so I returned to stock and CEL extinguished but returned on the next stert up. Now the same thing happens each time I retune or return to stock, the CEL remains extinguished until the net restart. I should add that the transmission shifting seems to be the only thing affected. Upon restart and CEL illumination the truck seems to shift like it has a tune installed. Stock the truck will shift up and down quickly and effortlessly whereas the non stock or tuned performance is more TC lockup where it shifts out and lugs around seemingly stuck in high gear forcing me to bury the pedal for kickdown. I'ts almost like the stock tune only remains until shut down then gets lost and needs to be reloaded. Any ideas?

[snoboy]

What turns on the CEL? Normally an emission related item, correct? Does the CEL turn on at a prescribed mileage in these trucks?

[briguy1982]

if trans is shifting funny it in itself can throw cel on as far as tune i would unhook the batteries and kill the memory it might have to much garbage to sort thru best of luck to ya

[snoboy]

Thanks for the response. If I disconnect the batteries will the computer default to the stock tune or do I need to reload the stock tune with the SCT?

snoboy

[briguy1982]

not likly anything is possible boot it may be more likly to accept the tune one thing is the torqueshift trans you might experiance so shift flare as it will need to relearn i had the same issue on a truck i disconnected the batteries and hooked them back up about 20 mins later than it would loud the stock tune back in only time had any problems is when i was switching between tunes often like every other day thats when mine basically froze up that worked for mine

[BBDS]

I have (2) 2004 F550's between the two there have been 5 Turbos, 4 injectors, 1 EGR cooler, several recals and a couple of times the boost hoses blowing off and my employees have never seen a CEL. I think Ford must have turned them off on one of the early recals. They have never come on.