Mazda 626 Dies on Highway


#1

My 98 Mazda 626 has died on me on the highway twice in the past two months. Conditions were the same in both cases: temps in the 90’s; air conditioner on; only driving for 15 min before dying; on highway in stop and go traffic. No engine lights come on and no warning is given before it just dies. After sitting for 20 minutes or so, it will start and run just fine. I’ve taken it to two different mechanics and they can’t figure out what is wrong with it. I can’t afford to buy a new car right now so any ideas are much appreciated!



Thanks -

Julie


#2

I suggest one of two things.

First, how often do you buy gas and where do you buy it. If your car still has winter blend, it may be vapor lock. Well, it still could be vapor lock. A weak fuel pump or several other issues may cause it.

Second, how old are the plug wires and coil (or the equivalent for your car? Maybe it is time for a change. Coils tend to be heat sensitive.

Now, maybe you can help.  What did the mechanics check?  What did they find?  Has anyone checked to see if there are any error codes stored in the computer? If so what exactly were the codes?

#3

Thank you so much for responding.
I don’t drive my car every day so I don’t get gas that often - maybe once every 3 weeks. I always try to go to a BP if possible. The tank was only about 1/8 full when this happened.
In April of 2004, I had to replace the engine of the car with a used one. The water pump went out unbeknownst to me, and I burned up the engine (a $3800 mistake). Anyway, at that time they put in new plugs and coils (I assume)so my guess is they are about 3 years old now.

I just paid $100 for a mechanic to hook it up to a diagnostic machine – he said that no codes came up. He suspected it might be the fuel pump but said it was a $800-900 guess. (I can get more info on exactly what he did if it would help). I’m a little embarassed to admit that this was at a well known muffler/brake kind of place. . .I have another trusted mechanic but he is about an hour’s drive away and he couldn’t diagnose the problem the first time either so I am reluctant to make that trip again. . .


#4

First, on a ten year old car, it’s time for the aged, dirty, fuel filter to start causing you problems. Change it. A fuel pump replacement is NOT something which has to be guessed at. There are various tests which can, and SHOULD, be done before a fuel pump replacement is considered. For some of those tests, you can see them at: www.carterfueldelivery.com/fuelpumps/supports.php. Download a copy for whatever mechanic who works on your car and starts talking, “fuel pump”.


#5

These kind of problems usually don’t set any codes unless there is a problem with one of the engine sensors. Sorry you spent the money and don’t get much for it.

The problem could be the fuel pump but I would suspect the fuel pump relay even more than the pump. The problem could also be with the ignition system. There is a test method you can use to help pin the trouble down when this happen again. Be ready for the trouble by carrying a spray can of starter fluid with you. Find out where the air intake for the engine is at then when the trouble occurs spray a one second burst of fluid into the intake. Then see if the engine tries to fire up. If it does then you know it is a fuel problem. If you don’t get any reaction then the ignition area should be looked at.