1995 Mazda 626 Problems: 6 Known Issues

On the 1993-1999 Mazda 626, both the FS 2.0L I4 and KL 2.5L V6 are prone to head gasket failure as they age, almost always downstream of a cooling-system problem: original radiators clog, plastic end-tanks crack, thermostats stick, and water pumps weep, letting the engine overheat and compromising the gasket (or cracking/warping a head). Symptoms range from coolant loss and white exhaust smoke to oil/coolant intermixing and heavy oil burning on badly failed engines. Because these are inexpensive older cars, deferred cooling maintenance is the usual root cause rather than a specific factory defect.

On the 1993-1999 Mazda 626, a very common driveability complaint on the 626 is an unstable idle that surges, dips, or stalls at stops, most often caused by a sticking or dirty idle air control (IAC) valve and, on higher-mileage cars, leaking intake manifold gaskets that create unmetered vacuum leaks (the gasket often leaks on the underside where it is not visible from above). The problem is worsened by carbon buildup in the throttle body. It affects both the FS I4 and KL V6, and because these are age/mileage-driven wear items rather than a single defect, it shows up across the whole 1990s run.

On the 1993-1998 Mazda 626, the ignition switch on 1993-1998 626s (and many other Mazdas of the era) was assembled with an excessive amount of grease at the internal contact points. Over time and with heat, the grease can carbonize, become conductive, and cause the contacts to overheat, reducing insulation and producing smoke and, in the worst case, a fire. Mazda issued NHTSA recall 15V674000 covering roughly 1.37 million vehicles, including the 626; the recall began December 17, 2015. Many original owners never received notice by the time these cars reached second/third hands, so a large share are still unremedied.

On the 1993-1999 Mazda 626 KL 2.5L V6, the 2.5L KL-DE V6 uses a cam-driven distributor with an internal O-ring/oil seal at the base and a shaft bushing. As the seal hardens with age, engine oil weeps up the shaft and pools inside the distributor cap, fouling the cap and rotor and shorting the ignition. On higher-mileage cars the shaft bushing also wears, allowing shaft wobble that both worsens the leak and disturbs the pickup signal. The result is a rough-running, misfiring, hard-starting or stalling V6 that many owners chase before finding the source. This is a well-known KL-engine quirk shared with the MX-6 and Ford Probe GT.

On the 1994-1997 Mazda 626 FS 2.0L I4 (automatic), the Ford-designed CD4E automatic transaxle fitted to 1994-1997 (5th-gen GE) four-cylinder 626s with an automatic is one of the most notorious weak points of the car. It runs hot, has undersized clutch packs and a fragile forward-clutch/valve-body design, and commonly fails anywhere from 60,000-100,000 miles. It was used behind the FS 2.0L I4; KL 2.5L V6 automatic cars used Mazda's GF4A-EL transmission instead. Repair shops have reported very high failure rates and the NHTSA/CarComplaints logs are dominated by transmission complaints for these years. A primary root cause was an inadequate factory transmission cooling circuit (a poorly designed radiator that did a bad job cooling the ATF). There was no recall, so owners bore the cost. The 626/MX-6 community regards a manual-transmission car as far more reliable.

On the 1993-2000 Mazda 626, eGR valve and intake passages clog with carbon causing rough idle, hesitation, and check engine light. Carbon accumulation in EGR passages restricts flow.