Recently, my GF's 1995 626 has been acting up. Sometimes under normal driving, usually around 3k RPM's, the CEL will come on, stay lit for maybe 7 seconds, and pop off. It randomly comes on, never stays on for long, and always pops right off.

This usually occurs at a constant ~3K RPM's, but sometimes if you punch the gas and the revs jump, it will pop on. I reset the ECU for kicks, and it didnt show up for a good 50 miles of driving...then the same thing started happening, except it comes on even less frequently now.

Any ideas? 1995 626 with ~87k, Auto Tranny I4. Any ideas/help is appreciated

 

The ECU might be detecting knock. I'm no Mazda fan but that does happen on a Honda when the knock sensor comes into play.

 

If you know someone with a Mazda diag connection, that's what you'll need. Unfortunately, every car built with computer controlled engine management and fuel injection can't be diagnosed very easily. SEL can mean any one of a million things, from throttle position sensor to O2 sensor, to timming, crankshaft, or cam position. You get the idea.

 

That's a common behavior for an o2 sensor error on the 626's.