Rough idle

[Hissss5]

When i start my 95 mustang 5.0 it idles like crap ( rpms go up and down)for a min. or so then the check engine light comes on, then the car idles fine.. i can drive it around after that with no more idling problems even with the check engine light on. it just does it on start up. the motor had some work done to it like cam,heads intake and so on.. do you guys think that i need to get it tuned to make it run good without it idling rough on start up? Im not sure if the guy i got it from did any kind of tune or anything....

 

[Njc0las]

Well, step #1: What does the check engine light code say when you get it read for free at any car place?

 

[Hissss5]

well it doesnt have a egr valve system at all and it reads the two 02 sensors are bad.. but thats just for the smog. I found out that the maf was bad and it was replaced ( the idle was rough then too, even driving it around town.. it would start to die at a stop light) so when the maf was replaced then it would run good around town but still having idling problems at start up.

 

[SVTCobra306]

Ensure you have no vacuum leaks (shouldn't) and that the 02 sensors are good, what cam is in it? I ran a crane 2031 for two years with a .030 over motor with no tune and no driveability concerns at all...

 

[Hissss5]

Thats the thing, I have no information about the engine at all.. My mech. tested all the vacuum lines for leaks and he said they were all good

 

[Hissss5]

If the 02 sensors were bad that wouldnt make it idle rough would it?