I am in the process of having my car tuned and my tuner seems to be coming up with excuse after excuse not to do it. Idk if there is something wrong with my trans, or if he doesn't know what he is doing. My trans has about 25,000 miles on it and was in the car when I purchased it. Previous owner had a sketchy tuner as well. It has always shifted weird and now that I put a new yank stall in along with a higher hp motor, it's worse. It shift nice and firm through every gear, but the pattern under light throttle is, 1-2-4 locked-3 unlocked-4 locked. WOT it shifts perfect, spot on every time. You can hold it in 3rd and it won't slip or gear hunt. But in drive under light throttle, it will do it every time. Wth is going on?

To add to this, along with the new motor, I went to a 5 wire 85 maf and he is saying the values are the same as the 78mm, but I am setting off a p0103 high frequency code at the same time. Could that effect the shifts?

 

No one has ever come across this issue?

 

Tune has to be wrong, you should only be locked in 4th. He needs to scrub tcc tables and max out the mph in 2nd and 3rd.

Check that MAS code and determine if it is reading too much air or too little. If Mas is off your commanded line pressure may not reflect engine load and trans pressure could be low. Get this corrected or you will burn something.

I am not an expert on this, but I dont see how an 85mm mas will have the same calibration as 78mm. The cross sectional area will cause a different mas reading for a given wire temp in the sensor.

I would get a new tuner..........