I had stalling and low idle issues.

My truck idles smooth at 500 rpm. 700rpm when AC is on.

When my truck dipped to lower rpms and stalled a time or two, it was all related to the IAC or TPS sensor. I just replaced both. All is good now.

 

** NEW UPDATE


damn it, i bought the map sensor and changed it, and it still doing the same behavior, the voltage goes down, start at 1.15-1.20 and as i push the throttle it goes 0.8 0.9v to 1.60v randomly but mostly 0.8v, ok im lost here, im in blank, dont know what to do, all would be fine but the smell coming from the pipe itches my eyes, it smell really bad, like poorly burned lp gas, there is a really bad combustion inside, random misfires when cold, and almost want to stall when i stop on red lights or bumps, and bad mileage, all spaks changed for mcc4 and tested coils, there is sparks on each, i really dont know whats next or what should i do now, pcm is new and updated, new fuel pump, and still dont want to work properly

 

The vehicle is most likely running very rich. Do you still have the old MAP sensor? And PCM? Clean the throttle bore and Idle speed motor and replace the TPS. You may want to do a compression test and scanner the vehicle for codes.

 

You pay attention, yes that is correct. You test at the middle wire to a good ground, like the battery. Just because your voltage isn't all the way up doesn't mean it's "bad" but it's not the best either.

With the smell I am now questioning your CAT, or bad plugs/spark in general. Have you replaced the pre-cat O2 sensors? Get them at www.rockauto.com and buy the Denso brand regular OEM plug in style. You can get both from there for the same price as one.

Duralast is just fine, ran them on a few rigs and their half the cost. NAPA Echlin is a good brand as well.

 

IAC and tps, 02 sensor and powersteering switch and crank and cam and vacume lines and sensors on the transmission causing it not too down shift right will cause is to act funny or stall without shooting codes. honestly change you crank sensor cause everyone underestimate them because its not showing the code and spends hours on looking else where the power steering switch adjust your rpms to adjust for the strain it puts on the motor but it i was you change the crank sensor check for vac leaks change cam sensor change transmission speed sensor and change the powersteering one if it dies when turning in that order and also when starting hold the gas down then play with it like a carb until it stays running. sometimes when the battery is off you can flood these things and are a bitch to start if you don't know that trick, having the gas flooredwhen starting tells it to cut back the fuel.