Hi everyone, this is my first time on the board and unfortunately it is with a problem. I bought my wife a 2005 GT back in October from a local dealership, she was in love because it has the ram air hood with Airaid Cold Air intake and flowmaster exhaust. The problem was since it was a dealership they couldn't tell me anything the previous owner did to it other than the obvious. That said, it ran great until last week. It came with the shaker 500 radio in it and I swapped it out for a new clarion head unit. Later in the day it threw a code P0506 Low engine RPM. The only thing I did was disconnect the battery...could there have been a tune that was erased with the battery being disconnected? I was told that even if it was tuned it would take a number of key turns for it to relearn the tune? Sounds off but at this point I am willing to try it. Thanks for the help.

 

You wont erase the tune. It does have to relearn the idle. If it runs alright now clear the code and see if it comes back.

 

Your tune will be fine. Double check your installation and the connections to the battery. A poorly connected battery can create a low RPM situation.

How low are the rpms?

 

Thanks for the help but I have checked and double checked the battery and everything is good n tight. The engine after about 15 starts is still "hunting" between 600-900 rpm. This is frustrating.

 

dirty MAF ?

 

I thought that as well but why would it start after the battery was disconnected and not before? I am using the wiring PAC kit from crutch field on the stereo...would that do anything? Also when I connect the battery there is a sound that resembles the horn from the passenger side but it is Not the horn.

 

Give it some more time. It took over 50 miles of driving before my 05 GT's wavering idle smoothed out the last time my battery was disconnected.

 

How old is the battery? If you aren't sure, take it and get the battery tested at autozone or advanced if you have one of those around you. I'm on my 3rd battery and I have an 05 as well. My last one (Interstate battery) was sitting at about half its CCA rating and was getting harder to start so I replaced it last week.

Don

 

If it continues to hunt after about 50 miles (which should be sufficient time for the adaptive learning to smooth things out), then a good TB and MAF cleaning plus a fuel filter replacement would be in order, especially since you have no previous history info.