Hello, I am a newbie so please bare with me. I just purchased a 1999 V6 Base Mustang with 122,000 miles. I have added a CAI, new platinum plugs & 10.2mm wires, new coil pack, fuel filter, cleaned MAF & IAC. I have a miss at about 1200 rpm after the car warms up. Seems to drive fine when cold. If I pull out from a stop and do it quickly, it doesn't hesitate. If I pull out normal and slowly drive it misses at 1200 rpm. I drive 35 miles each way to work so I can't keep driving with this condition. 3 different garages and no one can figure it out. Does not pull up any codes, and has never had a "check engine" light come on. Please if anyone could give me some insight, I would greatly appreciate it.

 

welcome

 

Hello, welcome. Post your questions in the tech section on this forum.The V6 members will have more insight.

 

tech section.

 

Did the car have any of those characteristics before you did the maintenance work? Does using higher octane fuel change anything?

 

I'm not sure if it did it prior to tune up or any of the work. I did it the morning after I bought it so I didn't drive it much before. I wouldn't think a tune-up or CAI or anything else I did would make it miss. It only does it whe its warmed up and I bought the car about 2 miles from my house, so didn't drive it long enough to see if it missed. I just put new EGR valve & EGR solenoid on today but haven't test drove it since. I'm leaning towards an 02 sensor or fuel injectors. I am going to try Seafoam later today.

Thanks for your input.

 

Oh, almost forgot. I had half a tank of 87 octane in the car, but I did top it off with mid-grade.