When leaving from stop light, stepping on the gas, then when shifting to 2nd over revs, then I have to let up on the gas to shift, then it takes off. I was told could be a bad MAF sensor or a shift band. A couple months back had filter changed and was told looked good, no chunks, fillings, or burnt fluid. How do I test MAF & trans? 2004

 

Never mind

 

Yes, a filter is cheaper than a repair, but I have still have xlint power. What would a filter have to do with shifting?

 

Never mind

 

Also you want to re-check ATF quantity using the proper procedure according manual for your year and model.

 

A proper fluid level check is good advice.

Do you have any codes? Are there any other engine or transmission issues? Why did you have it serviced?

After the fluid level there are many possibilities, what has you focused on the MAF sensor?

A proper MAF sensor test involves a check of the reported air volume at idle using a scanner with live data and then capturing the same value at a full throttle shift point and putting the engine values into a volumetric efficiency calculator to see if they make sense. This of course will be difficult when you can’t get a full throttle shift but you can probably get close by trying to capture the value as you approach the presumed rpm shift point under wot acceleration. You’ll need graphing capability or an assistant.


George

 

From the Blazer shop manual, the primary possibilities are:

Pressure regulator valve
Pump slide
Spacer plates or gaskets
Valve body pad
2-4 servo
2-4 band
Throttle position sensor
Vehicle speed sensor
4WD low switch



George