Ford Ranger won't idle in any gear.

[aonghus]

I've got a 1998 Ford Ranger XLT 4.0L V6 automatic, basically won't idle in any gear, only park and neutral. The check engine light reads that cylinder banks 1 & 2 are running lean.

What'ya guys think?

[MrQuick]

is the idle real low? Vacuum leak?

[68BNUT]

Just had that problem in my 99 F-150 and my buddy had the same problem on his 2000 F-250, It is definetly a Vacumn leak with poor idle and that particular code.

[aonghus]

Thanks fellas. His IAC was completley siezed, we pulled it off and nailed it on the ground, bunch of garbage came out, the car shifted into reverse just fine, but when we attempted to shift again, the ******* stalls out.

My money is on bad o-rings between the inake manifold upper plenum and heads.

Again, thanks for the responses. :git:

[68BNUT]

My Iac went bad It didnt throw a code in computer. Sometimes you have to grab and wiggle the hoses around to find the leak. A new IAC valve is only like 20 bucks. I did the same thing tried to clean my old one. it will go bad again.

[MrQuick]

I don't think smaking the IAC valve on the ground is going to help it at all. Once it gains computer control it will go back to where it was...put a new one on the retest.

[aonghus]

I must've been out of it when I posted that last response. We did replace the IAC valve, they're actually $60, not a big deal. The truck ran flawlessly for a day, no idle issues or stalling issues. But as I said, a day later, the truck stalls probobly 1 out of every 3 starts/shifts.

I used an OBDII reader and found that codes are lean cylinder banks 1 & 2, however all 3 of the O2 sensors passes. (1 O2 sensor is brand new)

I'm thinking, that the IAC valve was the primary culprit of the idle/stall issue, but that there is a vacum leak in the manifold somewhere causing the computer to throw codes for lean banks, while also contributing to the now much much better, but still annoying idle/stall problem. I've read in a few places that Rangers have O-rings that eventually go bad, causing the lean condition and error codes. So we'll replace the manifold gasket and go from there I think.

Oh, and Quick, I banged the IAC on the ground because this thing literally looked like the inside of an old gas tank. I used a flat head to free up the spring, car shifted once, but the solenoid in the IAC stuck in place and stalled the truck out from then on. I was 20 miles from home, and all the parts stores were closed, and I had no brak-kleen or carb-clean. Whats a guy to do LOL

[MrQuick]

I must've been out of it when I posted that last response. We did replace the IAC valve, they're actually $60, not a big deal. The truck ran flawlessly for a day, no idle issues or stalling issues. But as I said, a day later, the truck stalls probobly 1 out of every 3 starts/shifts.

I used an OBDII reader and found that codes are lean cylinder banks 1 & 2, however all 3 of the O2 sensors passes. (1 O2 sensor is brand new)

I'm thinking, that the IAC valve was the primary culprit of the idle/stall issue, but that there is a vacum leak in the manifold somewhere causing the computer to throw codes for lean banks, while also contributing to the now much much better, but still annoying idle/stall problem. I've read in a few places that Rangers have O-rings that eventually go bad, causing the lean condition and error codes. So we'll replace the manifold gasket and go from there I think.

Oh, and Quick, I banged the IAC on the ground because this thing literally looked like the inside of an old gas tank. I used a flat head to free up the spring, car shifted once, but the solenoid in the IAC stuck in place and stalled the truck out from then on. I was 20 miles from home, and all the parts stores were closed, and I had no brak-kleen or carb-clean. Whats a guy to do LOL

Ok, I was wondering, it sound like you banged it on the ground then just put it back on without replacing it. your getting close....