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Hi all.
As the title says I bought from ebay a used AP engineering unit and installed it to my S5 turbo. I also installed a 3 bar map sensor and a FD air intake temp sensor. I reseted the unit and tried to start the engine with no luck. The only possible problems that I could find is that the boost sensor reading is stuck to 4.99-4.98 all the time, even when the boost sensor is not plugged. So I guess that there is a problem with the sensor or the wiring that goes to the ecu. Can anyone help me troubleshoot this problem. I really have no experience with PFC and any help would be appreciated.
Also I hear a ticking sound coming out of the main solenoid of the rat's nest and a new kind of sound coming from the fuel pump when i turn the key
This is the
These are the readings of some sensors. The boost sensor value is always +1,92 so I guess that this confirms that there is a problem with the boost sensor.
Verify the map sensor is functional first. If it is then you will want to trace which wires run to the ecu for it and verify that aren't messed up in some way. Last option would be to run new wires entirely for the map sensor. This should be pretty easy to fix
Verify the map sensor is functional first. If it is then you will want to trace which wires run to the ecu for it and verify that aren't messed up in some way. Last option would be to run new wires entirely for the map sensor. This should be pretty easy to fix
Thank you for your reply. Do you happen to know any troubleshooting procedures for the sensor? Should I apply 5v to the one cable and measure resistance on the signal cable? Would that be enough?
No problem. I have been searching the forum for 19 years. I think that I should try to find out first if the POWER FC unit and the main wiring is ok. The map sensor is brand new and when I installed the stock FC boost sensor, nothing changed...the PIM value remained highlighted in black. Thanks anyway.
the ECU sends a 5v reference, and a ground to the sensor. then the sensor has the voltage reading back to the ecu, and if its 5v, the same as the reference voltage, its hinting that there is a short in the wiring
the ECU sends a 5v reference, and a ground to the sensor. then the sensor has the voltage reading back to the ecu, and if its 5v, the same as the reference voltage, its hinting that there is a short in the wiring
ok nice to know that. Thank you.
Do you happen to know why I get three stars (*** - highlighted in black) instead of the fuel temp sensor name? Does this imply that might also be a problem with the fuel system?
ok nice to know that. Thank you.
Do you happen to know why I get three stars (*** - highlighted in black) instead of the fuel temp sensor name? Does this imply that might also be a problem with the fuel system?
the FC doesn't have a fuel temp sensor, so the AP version of the PFC has it blocked off, as it were.
if its highlighted in black you have a problem with the harness, probably the same as the map sensor (same 5v reference)
Thank you for your reply.
Another strange reading in the sensor's monitor screen is that it shows my OMP in working condition. Let me explain what I mean...
My car has all the symptoms of an ECU limp mode when I try to boost it:
"Originally Posted by lastphaseofthis
Limp MODE
1. can only be activated by the failure of the OMP(oil metering pump), or it's cirucits within the ecu, usually when the OMP fries, it takes out the omp control within the ecu. NO other sensors will activate LIMP MODE.
2. after you start the vehical it takes about 4 seconds for the check engine light to come on, and limp mode to be active.
3. you cannot exceed 3500 rpm, or fuel will be cut to the REAR rotor.
4. You cannot exceed ~30 percent throttle, or fuel will be cut to the FRONT rotor.
you can down shift(to get above 3500 rpm) and floor the pedal and get no fuel at ALL."
I used a Mazda self diagnosis error checker and the car had 3 OMP errors (26, 27 and 37). No check engine light though.
So I thought to buy a POWER FC in order to by pass the problem, start to premix and use a better ECU than the stock one.
That's why I wonder why the POWER FC shows that the OMP is working. I thought that this reading should also be highlighted in black.
Does anyone know why this happens?
Well it never started so I didnt. I reinstalled the stock sensors and the stock ECU because I needed to drive the car. With the stock setup the car starts always even when its hot. Its my only car and almost a daily driver.
I live in a city with no rotary expert and the closest rotary garage is at least 220 km away. So I dont want to drive there with a limp mode. The car stalls every time that boost goes to positive pressure so any long trip would be problematic.
You already found the issue. Its a map sensor problem. Its not reading or is it reading and it thinks its at max boost. All you have to do is fix that and it should start right up. Use your energy troubleshooting that single issue. Have you tested the map sensor yet?
Thank you for your reply.
Yes I also thought that this might be the problem, but the fact that nothing changed when I connected the stock map sensor, or when no sensor was connected on the stock wiring, makes me think that there might be a short in the wiring. This will be really hard to find...
But of course I will try to check the map sensor too.
How can I provide the 5V power source to the sensor? I have an AC-DC adaptor but it provides up to 4.5 volts. Is this enough?
Does anyone know if I can use this cable to connect the map sensor directly to the POWER FC? My AP engineering PFC main unit has a similar 3 pin port on the side.
Also the map sensor that I have bought is this. Has anyone use it with the PFC?
not really, you already found it. engine harness, the 5v reference voltage wire (Pin 2I, Brown with Black) is shorting out on the Pressure Sensor signal wire, 2H Green with Yellow
not really, you already found it. engine harness, the 5v reference voltage wire (Pin 2I, Brown with Black) is shorting out on the Pressure Sensor signal wire, 2H Green with Yellow
either replace (N374-18-05ZG) or repair harness
The Brown/Black wire of the stock boost sensor wiring is the 5V reference? Are you sure? I thought that the Brown/Black was the ground and I had connected the sensor like this:
The Brown/Black wire of the stock boost sensor wiring is the 5V reference? Are you sure? I thought that the Brown/Black was the ground and I had connected the sensor like this:
What do you mean? My electrical engineering skills are kinda low...
Do you happen to know if I can use the apexi cable shown in the photo above to directly connect the map sensor to the main unit? Will this bypass the problem?
Not sure if this has been clarified but when you purchased your AP Engineering PFC, did it come with the patch harness for the ECU to engine harness?
Yes it has. Its a plug n play ECU that plugs to the stock harness. One thing that I dont know is why there is a single wire coming out of the patch harness. This wire has a metalic edge and I think that it goes to the speed sensor that is located behind the stock gauge panel. I will post a photo.
