hard cold starting (even when it's not cold)

[cozz]

90 model ranger, first start of the day, won't start unless I use starting fluid and floor it. used an obII code reader and got code 54 (iac circuit open, vane flow sensor out of range) Soo, I replaced the Iac sensor and still having same prob. Also replaced the pressure regulator at a guess before I did code reading. After I get it started once, it'll start all day long. Also when I unplug the IAC, before starting, it starts right up, course I get a check engine light.Any guesses here, thanks, Cozz

 

[RangerFabWorks]

my blazer has the same problem. got code telling me low activity in bank 2. meaning needs oxygen sensor. maybe same type of deal. and when yours starts, does it run rough?

 

[shadetree]

Usually a cold start/ok warm start problem is associated with the engine coolant temp sensor, or it's circuit.shady

 

[cozz]

yea that's what I was thinking, went ahead and replaced the coolant temp sensor, on the bottom of the intake. I haven't started it today, I'll update this later, think I need to find out how to test the MAF. I replaced the O2 sensor bout a yr ago, code reader helped me figure that out, not getting a code for that now