Blog
Fault codes, sensors and the tricks of diagnostics: what the codes mean, where to start checking and why a cheap adapter sometimes lets you down.
A blinking Check Engine, not a steady one: the difference
A steady lamp means «look into it soon». A blinking one means «stop». Two different messages, and the difference is expensive.
4 September 20262 min
The MAF sensor: signs of wear and a live-data check
A mass air flow sensor lies gradually. The car still drives, just worse — and the numbers show it before you feel it.
4 September 20263 min
The oxygen sensor: telling from live data that it is tired
The sensor rarely dies outright. Far more often it answers slowly — and live data shows it.
4 September 20263 min
Clearing a fault code: what "erase" actually does
The button turns the lamp off; it does not fix the car. And it erases exactly what the mechanic needed.
4 September 20263 min
ELM327 will not connect: a checklist in order
Nine causes, most common first. Eight of them are fixed without buying another adapter.
4 September 20264 min
Checking a used car before you buy: what a scanner shows
Fault codes get cleared before a viewing. But some traces cannot be cleared — and those are the ones to look at.
4 September 20264 min
The fuel cap: codes P0455, P0442 and P0457
Three codes whose culprit costs nothing in a third of cases and is fixed by hand in five seconds.
3 September 20262 min
Misfires: P0300, P0301 and why you should not keep driving
The one group of codes where «it can wait until the weekend» costs more than the repair itself.
3 September 20262 min
Fault code P0420: the catalyst or just a sensor
The most expensive-looking code in the book. And the most common case of replacing a thousand-dollar part for nothing.
3 September 20263 min