Just bought a used 2005 mustang 4.0 issues apparently
Throwing a code for EGR valve, we just replaced it
and cleared the code. It keeps throwing the same
code and is idling and sounds and runs like crap till
you approx 15 to 20 MPH, then it runs fine. It's also
now throwing a code for port incomplete. We know
absolutely nothing about cars history. We think its
possibly got cams that need tuned, but not sure.
It's just the 4.0 automatic. Any suggestions?
Putting a high performance cam in any engine will make it idle poorly and smooth out at higher speeds because the valves are now timed for higher rpm performance. But I also doubt mods would be done on that 300hp 4.0 liter V6 unless they wanted it to run like the Mustang V8. I'm not sure about "port incomplete", you'll have to Google that or talk to someone who does engine mods. Your engine computer will detect those mods and cause you concerns.
You have a carbon issue in the EGR ports,Starting with the throat of the throttle body,vacuum lines to the baro sensor, to as deep as the intake ports. Do not replace anymore parts!!! It is all a CARBON BUILD UP ISSUE.
How would I go about fixing that issue? Sorry I'm clueless.
send me a picture of the throttle body if you can. thanks
Here's a pic
Also noticed it will not start unless your giving it gas, and will not idle at all unless giving it gas.
Ok little more info, pulling my hair out here!!! Car will not start, idle or run unless RPM's are at least at 2000. Once your at 2000RPM, it smooths out and seems to run fine. We had to replace the radiator, waterpump, and EGR. All air filters are clean, doesnt appear to have any bad carbon buildup. We have discovered that something in the black box connected to the throttle body is making a loud pecking noise, it sounds very similar to the sound you hear when you have a rod knocking. Any thoughts?
So would a bad injector cause these issues?
Will try that, thanks!!
Did you also check for intake vacuum leak???
