OK. I’m going to sweeten the deal for anyone who helps me. I’ve got an ongoing problem with my stang and I’m so desperate that I’m willing to send anyone who helps me resolve this problem $50 either by Paypal or by check.
Let me start by specifying everything done to my car and then the symptoms.
I’ve got an ’02 5-Speed SOHC 4.6L. It has the following mods:
MAC Long-Tube headers
MAC Off-Road Pro-Chamber
Flowmaster 40-Series mufflers
Typhoon Intake Manifold
Steeda Dragon Plenum and Throttle Body
MAC Cold-Air Intake with 90mm MAF housing
Steeda Underdrive pulleys
Ford Motorsport 3.73 gears
Walbro 255 LPH fuel pump
Alrighty, onto the problem. I’m going to describe what the car feels like as best as I can. When you begin driving in first gear, immediately, you feel a subtle vibration in the engine, almost exactly the same as you feel when traction control kicks in. If you keep the gas at the same pressure, you feel this vibration throughout all the gears. If you get to a certain point in the RPM range in any gear and you ease off the gas to a minimum, the car feels like it jerks very little and the vibration disappears and it feels normal. It stays normal until you press the gas any harder than you were holding it before. Sometimes, the car will have the same vibration when you’re idling, and other times it won’t. There is no difference in response from the car whether the A/C is on or off. Obviously, this vibration is impacting acceleration a lot and it will take twice the time to get through the RPM range with this problem than it took when the car was driving normally. Sometimes, it will throw a code, but the codes vary so much that there is no rhyme or reason. I’ve gotten a code for lean in either bank and then the next time rich in either bank. Then I’ve gotten a code for a cam sensor but no matter what the code is, once I reset it, it never comes back. The latest was for incorrect reading in the upstream O2 sensors. I played with the EGR recently through my hand-held programmer and I thought it may have been stuck in the open position, but the problem persisted even when I turned the EGR system off and installed a small piece of aluminum between the EGR and plenum to block any possible leaks. Currently, there are no codes. One thing worth mentioning is that I’ve never once gotten a code for a misfire, which is the first thing I thought this could be when it originally started.
The following things were done/installed in effort to fix the problem:
Ford Motorcraft 255 LPH fuel pump and assembly
Ford Motorcraft fuel filter
Ford Motorcraft 19lb injectors
Cleaned/oiled MAC filter and let stand for 24 hours before re-installing
Cleaned the MAF sensor with carb-cleaner followed by electrical contact cleaner
I’ve pulled the wires off each injector and coil one by one but every single one produced the same result, the engine would idle even rougher.
In one final play of desperation, I played with the timing and A/F mixture through my programmer all to no avail.
One more problem I’m having is with the ABS system. A year ago, it started intermittently turning on and off until a few months back it turned off completely and never came back. I should point out that the main problem started happening before the whole ABS problem and the ABS has been off even when the other problem went into remission a few times.
Any input will be greatly appreciated.
Let me start by specifying everything done to my car and then the symptoms.
I’ve got an ’02 5-Speed SOHC 4.6L. It has the following mods:
MAC Long-Tube headers
MAC Off-Road Pro-Chamber
Flowmaster 40-Series mufflers
Typhoon Intake Manifold
Steeda Dragon Plenum and Throttle Body
MAC Cold-Air Intake with 90mm MAF housing
Steeda Underdrive pulleys
Ford Motorsport 3.73 gears
Walbro 255 LPH fuel pump
Alrighty, onto the problem. I’m going to describe what the car feels like as best as I can. When you begin driving in first gear, immediately, you feel a subtle vibration in the engine, almost exactly the same as you feel when traction control kicks in. If you keep the gas at the same pressure, you feel this vibration throughout all the gears. If you get to a certain point in the RPM range in any gear and you ease off the gas to a minimum, the car feels like it jerks very little and the vibration disappears and it feels normal. It stays normal until you press the gas any harder than you were holding it before. Sometimes, the car will have the same vibration when you’re idling, and other times it won’t. There is no difference in response from the car whether the A/C is on or off. Obviously, this vibration is impacting acceleration a lot and it will take twice the time to get through the RPM range with this problem than it took when the car was driving normally. Sometimes, it will throw a code, but the codes vary so much that there is no rhyme or reason. I’ve gotten a code for lean in either bank and then the next time rich in either bank. Then I’ve gotten a code for a cam sensor but no matter what the code is, once I reset it, it never comes back. The latest was for incorrect reading in the upstream O2 sensors. I played with the EGR recently through my hand-held programmer and I thought it may have been stuck in the open position, but the problem persisted even when I turned the EGR system off and installed a small piece of aluminum between the EGR and plenum to block any possible leaks. Currently, there are no codes. One thing worth mentioning is that I’ve never once gotten a code for a misfire, which is the first thing I thought this could be when it originally started.
The following things were done/installed in effort to fix the problem:
Ford Motorcraft 255 LPH fuel pump and assembly
Ford Motorcraft fuel filter
Ford Motorcraft 19lb injectors
Cleaned/oiled MAC filter and let stand for 24 hours before re-installing
Cleaned the MAF sensor with carb-cleaner followed by electrical contact cleaner
I’ve pulled the wires off each injector and coil one by one but every single one produced the same result, the engine would idle even rougher.
In one final play of desperation, I played with the timing and A/F mixture through my programmer all to no avail.
One more problem I’m having is with the ABS system. A year ago, it started intermittently turning on and off until a few months back it turned off completely and never came back. I should point out that the main problem started happening before the whole ABS problem and the ABS has been off even when the other problem went into remission a few times.
Any input will be greatly appreciated.