1997 Ford Ranger stalling and rough idling

1997 FORD RANGER
213,000 MILES • 6 CYL • 2WD • AUTOMATIC
Avatar
HALFMOONTOET
  • MEMBER
  • 2 POSTS
My ranger runs good while the weather is warm, but as soon as things begin to cool down it begins acting up. While giving it gas it runs fine but when you let off the gas it begins running rough. When you stop at a redlight or stop sign it will stall. It will stall running in park sometimes. I have had the Iac valve replaced and the pcv valve as well. trouble usually starts when weather dips into the 60's.
Nov 5, 2009 at 11:12 AM
Advertisement
Avatar
RENAUDTN
  • CAR REPAIR CONTRIBUTOR
  • 636 POSTS
Have you checked for trouble codes?
From your description of the symptoms, I’m tempted to think your IAT (intake air temperature) sensor may be defective. It’s located either in your intake manifold or it’s built in your MAP sensor (which is located in your intake manifold as well). Basically your computer relies on this sensor’s input to know the air density and changes the air/fuel ratio consequently.
Have your mechanic check that. If you’re mechanically inclined and you have a scan tool or a DVOM you can check this sensor yourself.
Let me know
Nov 5, 2009 at 4:32 PM
Avatar
HALFMOONTOET
  • MEMBER
  • 2 POSTS
I replaced this sensor and it has helped the rough idling a good bit, but It still stalls when I stop. It takes a few moments for it to stall and if I get to the gas pedal before it does I can keep it running. I'm sorry it took me so long to reply to you.
Nov 29, 2009 at 1:04 PM
Avatar
RENAUDTN
  • CAR REPAIR CONTRIBUTOR
  • 636 POSTS
hello there,

Glad the new sensor helped.
As far as your stalling problem, it could be a number of things. I would check the fuel pressure first. I would also check for vacuum leaks, and I'd take a look at my MAP and my TPS sensors.
Have you scanned the car for codes?
Nov 29, 2009 at 7:09 PM
Repair Safety Notice: This information is for general instructional purposes only. Vehicle repair can be dangerous. Verify all information, follow manufacturer service procedures, use proper tools and safety equipment, and consult a qualified repair shop when needed.