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Cold start idle help

Hello! I’m having a great deal of trouble with some idling issues. It started as a warm start idle it would fluctuate a bit then go to a steady idle. I decided to clean the maf sensor and used the proper cleaner to do so. I put everything back how it was and waited for it to dry. It all seemed fine. Now however a cold start it sometimes will stall and kick on the check engine and the battery light. Other times is will fluctuate and my interior lights will dim as it almost dies, then it catches itself and goes to the steady range. I’m not sure it the intake manifold o-rings I’ve heard to be a problem since it was happening at a warm start, now it happens with a cold start. The battery does leak a bit of acid from what I’ve seen so I’m thinking I’ll replace that and hope that was the problem. Any help at all would be greatly appreciated. It’s the 4.0L v6 xlt with 92k miles

Replace the battery first and see how it goes.

Just bought and installed a new battery, didn’t help it at all. Stalled out and had the check engine and battery light on. Then started rough again but it caught itself before it died and leveled out

So… what fault code was stored?

Sounds like the alternator is bad. Get it tested by a pro

No code was stored and the alternator test came back good…

Your check engine and battery lights will always come on when the key is on and the engine is not running. That is how you know those lights are functional.

Your engine stalling could be caused by too many things to list.

Honestly I think I may have fixed it. Took off the throttle body and it was completely black on the inside. There was so much junk in it. So cleaned that and got it looking all new and that this guy starts up so much better. My rpms are higher at idle and even on a cold start at starts like it just woke up.

Nice to hear you made some progress! I am not a mechanic, but the last time my CEL was on (turns out due to low ECT), he also read out “IAC dirty”.
The idle air control is a barrel-ish, 2 part assy about 6 inches long mounted horizontally with 2 10mm bolts with a “loose” gasket on side of intake manifold on right side of engine. After you get it off, take the 2 halves apart with the 2 phillips screws. The solenoid half should be fine. I used carb/choke cleaner (no idea if best, or really HIW to clean it), actually soaking the dual-chamber/pin-jet sensor half overnight in a bath (my clear cleaner came out light-brown). “Seemed” to help the idle over various operating conditions. Like now it doesn’t stall for example when shifting D/R or R/D in tight spots and traffic… Lmk
Also, very curious about your MAF and throttle body procedures! Tia.

Funny enough on my year model it has the iac valve doesn’t exist on my explorer, it’s a part of the throttle body… Which made me feel like an idiot. Cleaning the mass airflow sensor is easy you just have to be careful not to damage it. They sell a dual pack of cleaner at Walmart for the mass airflow sensor and the throttle body. The throttle body looked clean from the outside but after taking it completely off I saw all the black junk that was behind it. Relatively easy to do just takes a simple YouTube video look up to figure out how to do it.

Glad you got your idle problem fixed. The dirty throttle body problem is pretty common report here. It gets gunked up from the EGR and PCV valves, causing the throttle valve mechanism to not move as smoothly as before. I had to do that job or my Corolla a couple years ago due to an idle problem.