as i said in a previous post im working on converting a 1997 A4 1.8T to ME7.5 using an harness and ECU from an 03 B5.5 passat. i had to change the connectors at the firewall on the passat harness to make it compatible with the A4's body harness. i feel i have it wired right but the problem is when i key on the fuel pump comes on and runs constantly, the injectors have power constantly and so does the coils. now the really bad part about it is when i turn the key off and remove it the fuel pump, injectors, and coils still stay running! the only way to stop them is to pull the ECU relay by the ECU, unplug the red connector or unplug the large ECU connector. after i do any of those 3 the pump and everything stays off till i cycle the key again. to add to the problem when i pull the fuel pump relay the fuel pump still stays on. i have no idea how the pump is powering on without the relay on because according to the bentley manual if the relay is removed power should be cut off everything. can anyone here shine some light on this because im stumped.

what i ended up doing was not using the main ECU relay thats triggered by ground from the ECU. instead i fed that wire into the fuse block to trigger the fuel pump relay on which than powers the fuel pump on and off with the key. the up point of doing this is i dont get the fault code for the main ECU relay anymore. but for some odd reason when you use the actual fuel pump trigger wire along with the main ECU relay it put everything in some sort of constant power loop and everything stays on. by doing what i did above solved the problem and everything works.

well my problem now is the car will not start. the sensors i have swapped in to D connectors are the MAF, the DBW throttle body, coils, coolant temp sensor, wideband OXS, and MAP sensor. i repined and put the original square connectors on the harness for the knock sensors and the crank sensor. the cam sensor is original and i put the different trigger wheel in for the later ECU. i have 12V power on pins 3, 21, 62, and 121 at the ECU. i figured grounds would be natural when i grounded the wires under the expansion tank and on the valve cover. lastly i tested for 12v at the injectors, coils, and MAF which it has. the cam sensor and MAF also show 5V power from the ECU. lastly i dug out my oscilloscope to check the signals from the crank sensor and the cam sensor and both output nice wavelengths on the 0-scope. when i test the coils or injectors for them triggering on and off during cranking there is no pulsing from the ECU to either. i have no idea as to why it will not run because everything is there to make a fire in a sense but it will not trigger either coils or injectors. anyone have any insight on this?

yes i have the bentley manuals for both vehicles with full wiring diagrams. i have gone through the wiring with a multimeter several time and i even borrowed a friends B5.5 passat to trace out everything in the body connectors to see how its supposed to act and than try to simulate that in the A4. when i wire it how the B5.5 is with the ECU control relay (j271) in play my dash and everything now stays constantly powered instead of my fuel pump. when cranking in VCDS it doesnt show an RPM, injector pulsewidth, or spark advance. O-scope= oscilliscope. i use this to actually see the wavelength from VR crank sensor because that is the only way to visually see the signal from that sensor as it is not a pulse like the cam sensor. the cam is hall effect which is an on/off switch and can be seen with a test light. i will test the crank and cam sensor again today and post pictures of what my scope displays.

i do keep getting a fault still from time to time for the crank sensor and no signal but i know that can be a phantom fault. i figure the sensor is good because the car ran on the M5.9 on that sensor and when i scoped it where the sensor connects to the harness it had a good wavelength like i said above. what i said a few posts back is i put the square connector from the original harness on the new one so i didnt have to change sensor itself, i assume the crank sensors are the aside from the connectors. i may try to swap it out with another AEB crank sensor and if that doesnt work than i will install the original D connector back on the harness and put the later crank sensor back on it to see if that makes any difference.

EDIT: here is a screen grab attached from my oscilloscope of the 60-2 VR crank sensor. you can see the tooth count and the large dip is the 2 missing teeth. i have check the signal from the B5.5 to compare the signals.