1988 E-150 van won't stay running until it's fully warm
 

I have a 1988 Econoline E-150 with fuel injected 302 engine. Ever since it has started getting cold this year I'm having an issue with stalling that I didn't have in prior years with this van. When it's below 70f outside I will have to start it and immediately leave my foot on the accelerator revving it up until the temperature gauge goes above halfway, otherwise it will stall out. It seems to do fine when warm. Is this enough info to get an idea of what might be the issue? Anyone have something similar happen? I plan to keep driving it like this but it is kind of a pain having to sit in the driveway for 5-10 minutes wasting gas.

Thanks.

check the vacuum hoses