Today while i asked to re-check the throttle body harmess, as i want to order one but it will take a while for it to ship here, i turned the car on without the covers or the air filters and the cars rpms were jumpy, there was a hiss sound that was happening when the rpms went higher and stopped as they dropped to normal levels, then they would drop to slightly below 500 and back up.(this happens always you can see the rpms often jumping) Monday they’ll check, i think that might be causing the issue. Considering that the car has been checked by two dealerships and multiple shops and none noticed..

Now the car drops to around 11V with the new battery.

Do the throttle body harnes its like 24$ on eBay u just cut and splice the new one I'm sure that will take care of it

I'm looking for one closer to me otherwise i'll have to go with the eBay options ,$50 for the shipping, though it will take around a month for it to get here. :tapping:

An update: I got a throttle harness, however i did not need to install it yet. I noticed that the car generally felt bogged down and sluggish after checking a few things i noticed that the car was running hot and the temps were never dropping, turns out the thermostat wasn't opening at all or barely opening! I drove like this for at least two weeks that i know, during that period the transmission went and i've started having all sorts of troubles, anyone know what else may have been damaged that i may need to check and are you aware at what temp does the hot temperature warning come on, as i never saw that after my auxiliary fan and radiator broke, anyway i might open another thread to ask these. The issues did not come back until now.

These are the codes the car kept throwing when the issue occurred, when the engine malfunction light appeared the last two came up.
2D32 - Differential Pressure Sensore
2CF8 - Throttle potentiometer
2CFA - Throttle Potentiometer 2
2D13 - Air Mass sensor, rationality
2F03 - Intake air temperature signal

X2. Had similar problems with my car. My dash was lit up like a Christmas tree, limp mode, the works. Replacing the harness fixed my car. If you plug these OBDII codes into Identifix, it will point to a TSB about the harness.

Keep in mind that the "harness" in question is merely a plug connector with about 18" of wires coming out, the first 12" or so covered in black plastic sheathing. I got mine at my local dealer, they had them in stock, (tells you something right there). It was not expensive.