Truck stutters at low RPM only when very cold

[Wagonized]

my truck started stuttering today within the first 1 km or so of me driving it. Only below 1500ish rpm and it seems once some heat gets in the engine it goes away and runs as good as new.
It happened on two seperate occasions today after the truck was parked and had time to cool down. The last time when it started to stutter i gave it more gas which did nothing except make a backfiring type sound out the intake (or somewhere under there)

any idea what this could be? sounds like my mixture is off possibly.

Im thinking maybe plug wires or an 02 sensor going


thanks

 

[dogfriend]

Might be an ignition problem - plugs or plug wires

Not likely to be an O2 sensor - the O2 sensor doesn't do anything until the engine is warmed up.

Could be an issue with the IAC valve - not opening enough and causing the mixture to be rich - but opening the throttle would let more air in - it shouldn't backfire.

Maybe a problem with one of the temp sensors - Intake temp or Coolent temp

 

[Wagonized]

Might be an ignition problem - plugs or plug wires

Not likely to be an O2 sensor - the O2 sensor doesn't do anything until the engine is warmed up.

Could be an issue with the IAC valve - not opening enough and causing the mixture to be rich - but opening the throttle would let more air in - it shouldn't backfire.

Maybe a problem with one of the temp sensors - Intake temp or Coolent temp

do i have an IAC valve in my 91??

im going to try cleaning the maf today to see what that does

 

[dogfriend]

Yes, all fuel injected Fords have some sort of IAC (idle air control). Sometimes it may be referred to as an Air Bypass valve because it bypasses the throttle body to allow air into the manifold for idling.

http://www1.autozone.com/servlet/Ui..._us/0900823d/80/0b/98/f5/0900823d800b98f5.jsp

 

[Rhett]

Could be the plug wires or plugs as was said. Before I did that, I would probably run a $5 bottle of Sea Foam through the throttle body's vacuum port (it's underneath the throttle body). I'm not tryin to sell you anything, either...that Sea Foam stuff is just very good and it's cheaper than new plugs and wires. THEN if that doesn't help matters, look into the plugs n wires.