Heat and air weak at idle - 2004 Volvo XC90

[crw4bama]

My 2004 Volvo XC90 t6 the heat and air blows fine whe at consistent speed however when idling or just getting going it bogs down and doesn’t have the same strength

[jvl]

Does the blower itself bog down (blows air at same temp but not as powerful?)
Or is the blower consistent and does the temp lerature vary?

The first would indicate electrical trouble that arises at lower voltages (lower revs --> less alternator output). Could be a bad ground or corroded connection. Or dirty/faulty switch.

The latter would indicate a problem with coolant flow: thermostat stuck open, failing water pump, clogged cooling channels.

How is overall performance? Does the engine get up to temperature? How's the coolant level?

[oragex]

I would also think first electricals. Maybe check the controller on the blower

[jimmy57]

cabin filter plugged?

[crw4bama]

Same temp blowing but does idle rough has error code low air flow circuit

[crw4bama]

Does the blower itself bog down (blows air at same temp but not as powerful?)
Or is the blower consistent and does the temp lerature vary?

The first would indicate electrical trouble that arises at lower voltages (lower revs --> less alternator output). Could be a bad ground or corroded connection. Or dirty/faulty switch.

The latter would indicate a problem with coolant flow: thermostat stuck open, failing water pump, clogged cooling channels.

How is overall performance? Does the engine get up to temperature? How's the coolant level?

[crw4bama]

Bogs down when rpm drops I do have check engine light on and it low airflow circuit a

[ggleavitt]

Original battery? If not, how old is it? (With Volvo part marked batteries, sometime you'll see the manufacture date in YYWW stamped on one of the terminals). My vote is on battery and/or alternator regulator until both can be omitted as causatives.

[cn90]

Tstat and heater core are the usual culprits. I posted some DIYs in forum.

[oragex]

Maybe the alternator doesn't charge well. I'd test the voltage at the alternator and battery. 8'd also check all pulleys on the serpentine belt for turning smoothly by hand with the belt off. Also the timing belt tensioner should not shake and it's needle should be correctly positioned