RPMs drops on my 06 mustang gt

[Dylan R]

My RPMs will drop to 500 and raise to 1k in an instance and back down to 500 repetitively once I come to a complete stop with clutch in or even if I throw it in neutral. I have no issues with actually driving it, but it seems like it just wants to stall on me as soon as I completely stop. Clutch isn’t slipping and all fluids have been changed. I’m thinking it’s fuel injectors because it runs smooth as soon as I give it plenty of gas. Also gas mileage has taken a severe hit since this issue started occurring. No lights other than a service airbag. It has the bama plug in tune so I will reflash tune to see if that will fix it

 

[Eman]

Check engine light on? Any codes? Check for vacum leaks

 

[Dino Dino Bambino]

Thoroughly clean the inside of the throttle body especially between the blades and the bores. It's easier if you remove it altogether.
If that doesn't help, it's very likely you do have a vacuum leak. The drop in gas mileage does suggest that you have unmetered air entering the intake system. Check if any of the hoses coming off the intake manifold are cracked/broken/disconnected, and ensure that there's no air leak around the MAF sensor. If you don't find anything there, spray brake cleaner around the bottom of each intake manifold runner where they meet the head and see if the idle changes. A smoke machine will also help find any leak.

 

[darcman]

You really need a code reader. Years ago my 05 GT had exactly the same 500-1000 RPM issue thing. My old Predator was saying both sensors were bad on the throttle body. Well by the time I bought one or two sensors it was cheaper just to get a whole new throttle body. I got the Ford Racing TB for like around $150 I think...fixed

A nice thing just happened to me. A guy advertised on craigs he was giving away for free an SCT X3 and Steeda underdrive pulleys. He traded in his 06 GT, he said if you can use them they are yours. Well I didnt even email the guy because I figured he probably got a zillion emails. Then I figured what the heck. He said he did get alot of emails, but I was the only one that said I had an 05 GT and I wanted the stuff for my car...so he gave them to me. Probably all the rest just wanted the stuff to resell.

 

[StockishS197]

If it has only recently started happening (and not after any recent tuning), definitely clean the TB (take it off and inspect it, clean the butterflies). You could also check the MAF to make sure it’s clean, especially if you use an oiled filter. After you do all this, reset the KAM through your SCT device or unplug the batter for 15 mins. Then let it idle until you get to op temp, let it idle for 5-10 more mins with AC off, then a few more min with the AC on to let the car relearn the idle.

If it recently started happening after a tune, the tune might need some adjusting.