tl;dr my dealer had my car for a week to diagnose an intermittent electrical gremlin.
My maddening intermittent electrical gremlin was with my new to me Mazda3. Occasionally and randomly after in the first few months I had it the throttle would "go to sleep" during normal driving. By that I mean in the process of normal driving I'd suddenly have no throttle response, the car would go to idle, and the only way to get it back was to completely get off the gas pedal and it would respond again as usual. I'm appreciative that worked, but I couldn't shake the idea that if that were to happen during hard acceleration bad things could happen.
My first trip to the dealer yielded a recording in the event log of the throttle shutting off because it saw throttle and brake at the same time, an expected behavior I was told. I assured the mechanic and service manager that I was almost certain this wasn't the case, they had no other explanation, I continued to have the problem and made certain when it happened that I hadn't somehow been on both pedals.
After an email to Mazda's support line with some technical details hoping to get my situation into the right hands, I got a call from the dealer asking to hang onto it until they could replicate the problem.
The service manager or someone else in the shop drove it for the better part of a week, taking real time telemetry while they were in it while I was in a loaner.
Turned out that the problem was the second brake switch hanging on. I found out that there's one switch that talks too the ECU and another that talks to the brake lights, the former being the culprit.
Frustrating as could be, but like a good nerd I found the final diagnosis fascinating. I also wonder and would like to believe that my detailed and informed email to the mother ship made someone pass it up the line until it got into the right hands.
My maddening intermittent electrical gremlin was with my new to me Mazda3. Occasionally and randomly after in the first few months I had it the throttle would "go to sleep" during normal driving. By that I mean in the process of normal driving I'd suddenly have no throttle response, the car would go to idle, and the only way to get it back was to completely get off the gas pedal and it would respond again as usual. I'm appreciative that worked, but I couldn't shake the idea that if that were to happen during hard acceleration bad things could happen.
My first trip to the dealer yielded a recording in the event log of the throttle shutting off because it saw throttle and brake at the same time, an expected behavior I was told. I assured the mechanic and service manager that I was almost certain this wasn't the case, they had no other explanation, I continued to have the problem and made certain when it happened that I hadn't somehow been on both pedals.
After an email to Mazda's support line with some technical details hoping to get my situation into the right hands, I got a call from the dealer asking to hang onto it until they could replicate the problem.
The service manager or someone else in the shop drove it for the better part of a week, taking real time telemetry while they were in it while I was in a loaner.
Turned out that the problem was the second brake switch hanging on. I found out that there's one switch that talks too the ECU and another that talks to the brake lights, the former being the culprit.
Frustrating as could be, but like a good nerd I found the final diagnosis fascinating. I also wonder and would like to believe that my detailed and informed email to the mother ship made someone pass it up the line until it got into the right hands.