So I can't figure out why my car idle hunts. Throttle body is clean, I idle at 20 inches of vac or more depending on elevation and climate, I've replaced MAF, MAP, and my front O2 sensor. I can't figure it out. When I come out of gear, my idle will fall quickly to ~500 rpm, then bounce around up and down between 500-1200 a couple times, until I come to a complete stop, then it goes to where I have idle set.

I'm not sure if this is a related issue or not, but my cruising AFR is retarded. While doing 70 mph with cruise control on, my AFR will bounce between 13.2 and 16.4 and I can physically feel my car very slightly buck when AFR goes lean.

Anyone want to take a guess as to what my car is trying to do, or not doing? Is this tune related? I've been driving like this for a while, I haven't flashed a new tune in quite a few months.

Help me please!

 

thorttle body is bad.

 

So you think it could be worth it to buy a new TB and see if that fixes it? My current throttle body I purchased brand new and it has maybe 40k miles on it. I have had to manually open and close the butterfly valve on the inside to clean it. I've heard that's a no-no.

 

im having the same issue and mine idles in the 2k to the 3k range after i cleaned my tb im gonna have to bring to dealer because i heard time fixes it but i have a engine light on....