shifting problems 04 yukon xl

[kimo76]

thanks for reading this posting...my yukon has 170,735 miles on it ..i got it used ..I have been noticing a problem shifting from 2-3 gear. i have to pull my foot off the gas a bit for it shift when it does shift i also notice my rpm's will get to about 2,500 and my check engine will start blinking and i am doing about 55 mph. After i slow down check engine will go off . but i get no codes for this...i almost forgot i got a code one a few days ago when it first started doing this and it gave me a code for my TPS sensor and my speed sensor..i cleared it and they have never came back on....i also lose power going up hill....please help me ....thanks

 

[SLCHOE]

What code did you get?

 

[kimo76]

Not sure..I reset the computer with out writing it down..but have not gotten any codes yet ..other than p0300..ramdom misfire..but I don't notice any difference with the engine? ?

 

[SLCHOE]

The blinking Check engine light is to bring attention to possible catalytic converter failure. The most common cause for that light to blink is a misfire. Since you had a stored misfire code, I'd check that first. Engine issues can and will affect transmission behavior.

My first move would be to pull the plugs and change them out if they are worn. Clear the codes and drive it.

 

[kimo76]

Ok...thank you..let's see what happens..