Its more than likely a vacuum leak, basically air is entering the charge system that hasn't been metered by the Mass Air Flow Sensor.
What you can do is take a can of WD-40 and lightly spray your intake plumbing from Filter to Engine and see if the idle RPM changes. Don't spray directly onto the surface close enough that the liquid collects, just mist it from about 1 to 1-1/2 feet away slowly to see if you can pinpoint the location where the air is entering the intake system and then tighten up the connections if its at a joint, or replace your parts if there is a hole, for instance in a rubber piece.
I don't know how modified your car is, but if you have other supporting modifications to your car, but if you maxed out your stock Throttle Body (Which is highly unlikely if thats the only thing you've done to your car), you probably need to upgrade your ECU and possibly your Camshaft.
Also, if I may make a suggestion to you about your modifications to your car. If you've done all of this intake work, with no other supporting mods. You aren't going to get very far as far as Horsepower, Throttle Response, or Torque. You only need to upgrade how easily the air can get into the engine if you start getting into some Head-work, some light-bottom end work, and a very good exhaust. The most you'll see out of these modifications is 10-15 peak horsepower, and you probably actually lost some throttle response. I recommend you put the car back to stock and start upgrading the engine from the other end starting with the exhaust. A set of headers, a free-flow true-dual exhaust and a mild camshaft will do absolute wonders for Horsepower, Throttle Response, and Torque-band, not to mention if you do all these things, at that point you could start adding some intake upgrades.
I hope I didn't offend ya by this post, I'm just truly trying to help ya man from a hardcore gear head. Hehe
May 16, 2008 |
2002 Ford Mustang