My 944 NA has a intermittent hesitation when cold at mid throttle. I've replaced AFM with refurbished and no real change. It runs well other than this and when its warm its fine.
Any ideas?

 

How cold is "cold?" Here in the Northeast, I get a similar hesitation and "chugging" (for lack of better words), until it is warmed up, usually around 1-2 minutes. Go easy on the gas and turn the heat off until it is warmed up. Try thinner oil in the winter months which helped mine.

 

Its worse in the morning may 25 deg F currently but generally worse first 1/4 mile and slowly improves as the engine warms.

 

Sounds like mine. Has been the same for the past 20 years that I have owned this vehicle. I wouldn't worry about it in cold weather. If it is still the same in the summer, then it could be leaking injectors, a bad coolant (DME) temp sensor, or worst case, a leaking head gasket allowing coolant to seep into the cylinders and cause rough running until it burns off.

 

i just figure the cat needs to warm up or something lol

 

Thanks, I was wondering about injectors but couldn't make the connection but I guess they could leak before things warm up, expand and seal.

 

there's no cat after market exhaust
of course it could be like me and just not like the cold or mornings !

 

Check the DME temperture sensor:
http://www.clarks-garage.com/pdf-manual/elect-19.pdf

 

Thanks, I'll take a look.

 

I have exactly the same issue! Never thought to look into it, always fine after its warm as you guys said as well. Thanks for the info guys!