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Hello Xpensiveobcesions, Look for a dirty throttle plate. Remove the snorkel that goes from the air filter box to the throttlebody. Manually open the throttle plate. Dirt builds up on the back side of the plate and around the bore where it sits in. When dirt builds up, it closes off the air gap that allows air to flow past. When this happens, idle becomes too low and stalling insues. Use carburetor or throttlebody cleaner and a brass brush to clean the dirt, then wipe things clean with a rag. See if that helps at all. Let me know.
Your JA Expert,
I did so,I pulled the intake plenum the MAF and the throttlebody off to insure a good clean. While those were off I also cleaned what I could from the intake manifold just inside a little bit. Cleaned the intire air intake system with carb cleaner and even cleaned the little idle hole on the throttle plate. As of right now i'm still having issues with it, drove it around for about 20 miles and its still happening, if that was it my guess is that it would be an instant fix. So the problem still exists.
I do agree, if that was it, it would have been better right off the bat, so now we have to get deeper. The next thing we need to verify is what is the fuel pressure when you start the car the first time. That car should have a test port on the fuel rail, so you will need a fuel pressure guage. Here is your spec.
Let's see where that leads us and we'll move forward from there.
One other thing, I haven't seen it on your car, but it's worth checking none the less. Locate your fuel pressure regulator on the fuel rail. Disconnect the vacuum line from it and see if there is fuel present in the vacuum line. If there is, that's the problem and excess fuel is entering the engine. You may have to check several times and look with the car running and just after shutting it off.
Ok so I tested the fuel pressure and it tested between 45 and 46 psi. Also I checked a couple vacuum lines from the rail to the throttlebody (only ones I could find) and both on both sides of the tube were dry/no fuel present. What would be next?
Ok, the next thing is a little harder to test since you don't have a scan tool. On the throttlebody, you have an Idle Air Control motor. It is located as #5 in this diagram.
I am attaching a description of what this device does. It has a tapered pintle that closes of an air passage then opens up the cap to regulate a specific idle speed. If that pintle is getting stuck into the seat or the motor is getting stuck not allowing it to retract, it could be causing your issue. Again with out a scan tool, it's impossible to operate. You can remove the 2 bolts and remove it. The pintle and seat get dirty like the throttlebody, so clean them and let's see what happens. Do not push the IAC in, or you'll have to drive it to allow it to move back into it's proper position.
CIRCUIT DESCRIPTION The Idle Air Control (IAC) valve is located in the throttle body of both the Throttle Bowl Injection (TBI) and the multi-port fuel injection (MFI) Systems. The IAC valve consists of a movable pintle, driven by a gear attached to an electric motor called a stepper motor. The IAC valve motor is a 2-phase bi-polar permanent magnet stepper motor that is capable of highly accurate rotation, or movement, every time the polarity of a winding is changed. This change in polarity can be seen when observing a test lamp connected between ground or B+ and an IAC valve circuit while the PCM is attempting to change engine RPM. The test lamp will flash ON or OFF each time the polarity is changed. The Powertrain Control Module (PCM) does not use a physical sensor in order to determine the IAC pintle position, but uses a predicted number of counts. One count represents one change in the polarity, which equals one step of the stepper motor. The PCM counts the steps it has commanded in order to determine the IAC pintle position. The PCM uses the IAC valve in order to control the engine idle speed. The PCM does this by changing the pintle position in the idle air passage of the throttle body. This procedure varies the air flow around the throttle plate when the throttle is closed. In order to determine the desired position of the IAC pintle at idle or during deceleration, the PCM refers to the following inputs:
When the ignition key is turned OFF after an ignition cycle, the PCM will first seat the IAC pintle in the air bypass bore and then retract the pintle a predetermined number of counts in order to allow the proper amount of air to bypass the throttle plate for engine start-up. This procedure is known as an IAC reset.
Also here is a picture of the fuel pressure regulator. The vacuum line that attaches to this unit is the one you need to check. I think your engine has a plastic cover on it. You most likely have to remove that plastic cover to see this item.