Hello everyone,

A couple of months ago I replaced my throttle body equipped with a new throttle body position sensor. It was a decent price and it looked to be in good shape. Got it off ebay and it totally came from China. It came from a relatively low mile D2 apparently. When I received it I has a replacement throttle body heater plate ready to install with a silicon gasket. As an aside I squished the silicon gasket and it leaked everywhere. My rec is to stick with the normal non silicon gaskets for the throttle body and heater plate. Anyway, when I initially inspected the replacement throttle body it looked squeeky clean and I realized they probably hot tanked with caustic or acid cleaned this thing because under the throttle body heater plate once removed was crusty and white under. Maybe they disassembled prior to cleaning but I doubt it.

I tried it out simultaneously as the first fire up after installing the Inline thermostat mod. I went to try and pedal to 2500 rpm to buzz the bubbles out of the coolant per the recommended bleed procedure for the inline mod, and the throttle body behaved extremely poor. It over revved and held at 2800 rpms when I did not have my foot on the throttle.

I noticed the aforementioned throttle body heater plate coolant leak after shutting the engine down and swapped the heater plate to the previous throttle body and everything went back to norm.

Any ideas why this happened? Both are photographed below, they seem to be like for like but who knows? I am at a position where I am about the replace the throttle cable so maybe that was it?