Okay guys.. to start.. Its a 99 Stang GT. (4.6L SOHC) The car has BBK Long tube headers, X-pipe, MSD Ignition, CAI, Under-drive Pulleys, Stage II Clutch, Steeda Short-throw shifter.. everything else is believed to be stock on the car.
The car used to hesitate at idle and jump up and down and sometimes get so low that it would stall. Also, if I rev the engine up.. the engine wants to stay there for a few seconds before climbing back down.
I first tried Idle Air Control Sensor, this didn't change anything.
I changed the Air Charge Temperature Sensor & Cleaned out the entire throttle body.
-this seemed to have stopped the fluctuation at idle but..
The car still climbs rpms and stays there a few seconds before coming back down, as well as imbetween shifts.. the car wants to stay at those rpms with out free-falling. As well if your just cruising down the street and put it in neutral, the cars rpm's bounces up and down between 1000 - 1500rpms until you come to a stop and/or put it in gear.
The rear O2 Sensors have been disconnected from previous owner, but I don't think this would cause this issue.. but I could be wrong? (I plan to get those changed and plugged in ASAP.
What sounds to be the issue? Vacuum leak? Suckin air somewhere? EGR fault? Throttle Position Sensor?
I'd like to get some help where to start before spending a bunch of money on sensors that may not even need to be replaced.
Thanks in advance for you inputs!
The car used to hesitate at idle and jump up and down and sometimes get so low that it would stall. Also, if I rev the engine up.. the engine wants to stay there for a few seconds before climbing back down.
I first tried Idle Air Control Sensor, this didn't change anything.
I changed the Air Charge Temperature Sensor & Cleaned out the entire throttle body.
-this seemed to have stopped the fluctuation at idle but..
The car still climbs rpms and stays there a few seconds before coming back down, as well as imbetween shifts.. the car wants to stay at those rpms with out free-falling. As well if your just cruising down the street and put it in neutral, the cars rpm's bounces up and down between 1000 - 1500rpms until you come to a stop and/or put it in gear.
The rear O2 Sensors have been disconnected from previous owner, but I don't think this would cause this issue.. but I could be wrong? (I plan to get those changed and plugged in ASAP.
What sounds to be the issue? Vacuum leak? Suckin air somewhere? EGR fault? Throttle Position Sensor?
I'd like to get some help where to start before spending a bunch of money on sensors that may not even need to be replaced.
Thanks in advance for you inputs!