Join Date: Apr 2009
Location: Hebron, Indiana
Well after 130,000 miles I started getting code P0506. I got it a few times last spring and now that the temperature dropped the problem returned this fall. The description is idle speed too low. Watching the engine speed on my Scanguage, I saw that the code usually happened when stopped at a traffic signal for a minute or more and the RPM dropped to the low 500s.
One of the listed fixes listed is to clean the throttle body. So I decided to do that first. It only takes about 45 minutes. I had never done it in 130,000 miles on this vehicle. After removing the throttle body I found it to be dirty, but not extremely dirty. (I have cleaned a few throttle bodies in my life.) So I assumed that cleaning it would not fix the issue. I cleaned and polished all surfaces and removed any trace of the oily dirt.
Upon re-installation I found that the idle had increased to the 650 or 700 range and it idled much smoother. It never drops to the 500s. I have put about 120 miles of city driving on it. The P0506 and slow idle seems to be gone.
So if you experience a P0506, I suggest that you do as others here have recommended and clean the throttle body first.
2005 White 2wd Z71 WT
Last edited by n9cv; 11-23-2016 at 10:10 PM.