problems with down shifting on 2005 Hyundai Santa Fe

My 2005 Hyundai Santa Fe (91,000 miles) is not
down shifting right. When I let off gas to coast, it acts
like its either going to die or down shifts hard.
Been doing this through 3 or 4 tanks of gas, so I know
it is not bad fuel.
Also, rpm is running high.

Asked by for the 2005 Hyundai Santa Fe
2 answers 4 comments
sounds like your transmission is having a problem, the PCM may be intermittently failing, the MAP, MAF or TPS sensor could be bad or going bad. let me know if you find out the solution.
I took it to the Hyundai dealership and had a scan ran on it. Had transmission fluid flushed and
a new timing belt. Will see what happens. Thank you for your response.
Check engine light on 'check codes,sounds like bad IAC motor ,idle air controller or tps sensor throttle position sensor..
My check engine light is not on. Thank you for the response, any idea of cost in these possibilities?
most likely your TCM (trans control solenoid). some places call it the PCM (powertrain control module). looks like this is a common problem on these vehicles. which engine is in your vehicle?

RR
Have found out (after spending a lot of money) that it is the
tps. Will be a fairly cheap fix.
Thanks to everyone who offered help.
I truly appreciate it.