Engine Over Heats Only When Ac Is On

[sm00thpapa]

My engine seems to over heat when I turn on the AC. Other than that it runs at normal temp. It is a 2004 Isuzu Ascender with the GM 4.2 Inline 6 Vor-Tech.

[txab]

Check to make sure radiator fins are clean. Same goes for the condenser. Check operation of fan. If fan is weak, lazy or is not locking up then you're not pulling enough air through the condenser and radiator

[markw8]

Has the coolant ever been changed? Possibly a partially clogged radiator.

 

Mark

[sm00thpapa]

Put a new fan clutch, water pump and changed the coolant and still over heats when the AC is on. Now when I am at idle speed it idles erratically and cuts the engine off.

[sm00thpapa]

Now the engine stumbles at idle speed with either the AC or heat on. What can it be? Please share some advice or if anyone has ever experienced this issue. Thanks...