I have a AEM AFR guage which has been giving odd readings for a while now. Today it just stopped. When I got the car back after the clutch and flywheel swap I found the sensor to be very loose in the thread and it'd been rattling about and the wiring had been left laying on the exhaust and the protective sleeve had totally melted. I'm hoping these 2 issues have wrecked the sensor but how can I test it?