Car seems to be running lean? It idles fine without any surge but when at wot you can hear a huge surge of air being sucked in, slightly bogs and it takes a second for it to rev up. You can really tell while driving that the throttle response isn't snappy. All is stock with the motor except what's listed below... and I just changed the plugs, cleaned the MAF with MAF cleaner then took the throttle body off and cleaned that real well also. No vacuum leaks anywhere and yes the cel is on but I don't know the codes at this point. Bought the car used recently and it's been this way from day one. What I've added is the CAI. Any suggestions or think it needs a tune?




Mods:
BBK Cai
Catless 3" Magnaflow o/r X-pipe (no 02 sensors that I can see)
Magnaflow resonators
SLP LM1 axle backs
MSD Ignition

 

I had the same problem with my 96 gt mustang when I bought it. I had a real bad suction coming from my throttle body and the cel was on. I had to plug a hole on the bottom of my throttle body, it was to much un metered air coming in. It took care of half of my problem the other half was a bad o2 sensor. Since then my car runs perfect.

 

Let me know if u need a pic of where at on the throttle body the air was coming in.

 

Also had to replace purge flow sensor. For some reason the 96 model are bad for these little sensors going bad.