Hey guys, new member here but always reading up on the forums.
So I have a 2004 GT with an 03 Mach 4v swapped in. No crazy mods, just an x pipe, cat back and 4.10s. Car runs great most times but once it runs for about a minute the idle surges for about 15-30 seconds and goes all the way up to 1500-2500 and stays there regardless if I turn it off and back on. I know these 4.6s have that hanging idle till you come to a stop and I can deal with that but this thing never comes down. Well, some days it'll be fine and then some days it idles really high.
Things I've done/cleaned:
New air filter
Cleaned MAF
Cleaned TB(multiple times)
Cleaned IAC/replaced gasket(now has restrictor plate)
Checked for vacuum leaks(smoke machine)
Cleaned all connectors(compressed air)
I'm stumped because sometimes it idles just fine at around 850-900 and then some days it 3x that. Again, I'm not worried about the hanging idle that drops after a few seconds that these 4.6s do, it's the constant high idle that's driving me crazy.
If you guys have any suggestions on what I should do, I would greatly appreciate it.
So I have a 2004 GT with an 03 Mach 4v swapped in. No crazy mods, just an x pipe, cat back and 4.10s. Car runs great most times but once it runs for about a minute the idle surges for about 15-30 seconds and goes all the way up to 1500-2500 and stays there regardless if I turn it off and back on. I know these 4.6s have that hanging idle till you come to a stop and I can deal with that but this thing never comes down. Well, some days it'll be fine and then some days it idles really high.
Things I've done/cleaned:
New air filter
Cleaned MAF
Cleaned TB(multiple times)
Cleaned IAC/replaced gasket(now has restrictor plate)
Checked for vacuum leaks(smoke machine)
Cleaned all connectors(compressed air)
I'm stumped because sometimes it idles just fine at around 850-900 and then some days it 3x that. Again, I'm not worried about the hanging idle that drops after a few seconds that these 4.6s do, it's the constant high idle that's driving me crazy.
If you guys have any suggestions on what I should do, I would greatly appreciate it.