RPM Issues
03-28-2013, 11:56 AM
#1
2nd Gear Member
Thread Starter
Join Date: Jan 2012
Location: Tennessee
Posts: 481
RPM Issues
Warning, this is going to be a long post...
Ok, so, my 2010 GT, with automatic transmission is having some RPM issues (still).
While STOCK: When coasting, the RPMs will drop from 1500rpm to 1000rpm, then rise back to 1500rpm and then fall gradually. When coming to a complete stop, the rpms will surge from around 650rpm up to 1000rpm, and settle back to idle.
When Steeda Tune and CAI installed: When coasting, RPMs will bounce constantly up and down from 1000rpm to 1500rpm, until I get to a point slow enough that it will fall to 1000rpm. When coming to a complete stop, the RPMs will surge from around 650rpm to about 1200rpm, then settle to idle (you can feel the car lurch forward).
I have cleaned the throttle body, I have cleaned the MAF sensor, recleaned the air filter with LIGHT amount of recharge oil.
Took the car to a dealer returned to stock, and they tell me the rpm issue when coasting is because the torqued converter is disengaging, and this is "normal". When coming to a complete stop, he tells me the surge is "normal", that it is something that Ford has it programmed to do for fuel economy.
So, my questions are: Is this normal behavior for a stock mustang?
I had the issues also with Bama Tunes, thought it was the tune, but I get the same issue with the Steeda tunes. So what is wrong with my car? Any suggestions?
Ok, so, my 2010 GT, with automatic transmission is having some RPM issues (still).
While STOCK: When coasting, the RPMs will drop from 1500rpm to 1000rpm, then rise back to 1500rpm and then fall gradually. When coming to a complete stop, the rpms will surge from around 650rpm up to 1000rpm, and settle back to idle.
When Steeda Tune and CAI installed: When coasting, RPMs will bounce constantly up and down from 1000rpm to 1500rpm, until I get to a point slow enough that it will fall to 1000rpm. When coming to a complete stop, the RPMs will surge from around 650rpm to about 1200rpm, then settle to idle (you can feel the car lurch forward).
I have cleaned the throttle body, I have cleaned the MAF sensor, recleaned the air filter with LIGHT amount of recharge oil.
Took the car to a dealer returned to stock, and they tell me the rpm issue when coasting is because the torqued converter is disengaging, and this is "normal". When coming to a complete stop, he tells me the surge is "normal", that it is something that Ford has it programmed to do for fuel economy.
So, my questions are: Is this normal behavior for a stock mustang?
I had the issues also with Bama Tunes, thought it was the tune, but I get the same issue with the Steeda tunes. So what is wrong with my car? Any suggestions?
03-29-2013, 09:36 AM
#3
5th Gear Member
Join Date: Apr 2008
Location: Acworth, GA
Posts: 3,666
I've had this issue "off and on" since I've owned my car, stock and with custom tunes. Over the past year, I wasn't experiencing the high idle issues, then I recently replaced out my thermostat housing and the issue started back up. :-/
I have a manual, so it typically idles high when i slow down and shift into neutral.
I have a manual, so it typically idles high when i slow down and shift into neutral.
Last edited by kevinmalec; 03-29-2013 at 09:49 AM.
03-29-2013, 09:37 AM
#4
There's a few different things this could be. I would recommend checking/cleaning the Idle Control Valve, MAF and Throttle Body! Also, check for all vacuum leaks.
This is the first place I would look. Since it looks like you already have a Bama tune, if you'd like to you can give my Bama team a call and they'll walk you through this process and help you troubleshoot then get you a revised tune file sent out!
Let me know if you have any questions or need some assistance. I hope this helps! Our Bama Performance tuning specialists are here in the building Monday-Friday from 9AM-5:30PM EST and Saturday 9AM-5:30PM EST. You can hit them up directly at 888.226.9764 and they'll get you squared away!
-Dan
This is the first place I would look. Since it looks like you already have a Bama tune, if you'd like to you can give my Bama team a call and they'll walk you through this process and help you troubleshoot then get you a revised tune file sent out!
Let me know if you have any questions or need some assistance. I hope this helps! Our Bama Performance tuning specialists are here in the building Monday-Friday from 9AM-5:30PM EST and Saturday 9AM-5:30PM EST. You can hit them up directly at 888.226.9764 and they'll get you squared away!
-Dan
03-29-2013, 10:24 AM
#5
2nd Gear Member
Thread Starter
Join Date: Jan 2012
Location: Tennessee
Posts: 481
Dan, I HAD a bama tune had 3 different revisions, and didn't sort it out, so I went with Steeda. Now, same issues. The newer 4.6L have an "open flow" idle air control system, it goes from the valve cover on the driver side to the intake manifold behind the TB, and from the air intake hose just in front of the TB to the valve cover on the passenger side. It's not really something to be cleaned.
Also, PLEASE note I have already cleaned the TB and MAF, so that is not the issue.
Also, PLEASE note I have already cleaned the TB and MAF, so that is not the issue.
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