I'm having a problem with my 99 Mazda 626. It has 90,000 miles and has recently been slow to start. I had the guys at Pep Boys check out the battery (since it was still under warranty) and it checked out fine. They also cleaned and tightened the battery connections and checked the starter and alternator. Everything checked out okay, but still had the slow start problem. Then tonight it wouldn't start - it began to start but gave out. Now it won't turn over at all. I even let it sit for awhile and tried to start - still wouldn't turn over. The check engine light has come on from time to time, but only after driving for 20 minutes (or more) straight. It will usually go off the next day and hasn't been flashing. Any suggestions as so what's going on? I'd appreciate any help I can get.

There are a couple of possibilities, but the most likely one is a battery that has an internal problem that won't let it hold a full charge.

This typically (but not always) also manifests itself as a reduction in the amp-hour capacity of the battery.

This can be measured by monitoring the voltage while the battery's under a specified current load and timing how long it takes for the voltage to drop a specified amount.

Take the car back to them and give them another go at it.

Everybody benefits, so post back and let us know what the problem turns out to be.

Actually, they did check the voltage on the battery and it was pulling the full voltage. He suggested having Mazda dealership check the oxygen sensor. I'm planning to take it to the dealer today - so I'll let everyone know what they tell me.

There's no way an oxygen sensor will cause slow cranking. I think there's been a miscommunication regarding the nature of the symptoms.

Slow cranking: The engine rotates at a slower number of revolutions per minute than is normal while it's being cranked.

Slow starting: The engine has to be cranked longer than normal before it starts.

Some of the things Pep Boys checked when you first took the car to them can be associated with a slow cranking problem.

.. I had a plymouth colt that did exactly the same thing, we thought it was the Alternator then the battery, prehaps the Starter... but no it turned out to be the Distributor. So i'd get that check, but before you do, make sure it isn't just a water or Fuel filter.

i have an 89 mazda 626 that did the exact same thing i replaced the battery i my self took out the starter and had it tested that wasnt the problem i installed a new alternator and it still wouldnt start. so i checked all of the fuses under the hood and behold there was my problem a $4.00 project turned into a $100 project. there should be a black fuse box next to the battery. check em' out.