Can confirm this. I’m working on an app that uses these BLE adapters to communicate and have been successful in abstracting my code to talk to most of them (VEEPEAK, VGate, etc.) The really cheap ones will still communicate, but the format of the responses aren’t as predictable.

Sounds like you have a vacuum leak somewhere and something in your cooling system that you disturbed wasn’t put back or installed correctly.

I’d go over the recent work carefully and check for anything that looks off.

Check the relay control module