Mechanics

99 4 CYL AUTO- OCCASIONALLY IT WILL NOT START - RIGHT AWAY - BUT EVENTUALLY DOES.

1999 Mazda 626 • 16,000 miles

99 Mazda 626 4 Cyl Auto- Occasionally it will not start right away. It will just turn over and over without starting. Battery is strong. Then, once I hear the fuel pump come on, it will start. When I do not hear the fuel pump come on and have tried to start it a few times unsuccessfully, I merely "bump" the key / ignition until the fuel pump cycles on, then it will start right up. This has worked every time so far. This started happening intermittently about 6 months ago. At first we didn't bump but just continued trying to spin it over and over and over. Sometimes it would take 20-30 minutes of trying at intervals before it would fire.
Another item: Sometimes you will turn the key and nothing - no power, no clicking, nothing - then turn the key off completely and then try again and all is normal - this may be unrelated as they usually do not happen together but started during the same time period.
Thanks for any help.
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Morkfromork
July 3, 2012.



Maybe you should start by checking the ignition switch. Seems it is intermittently not making the correct connections. If it is the ignition switch, both problems should be related.

KHLow2008
Jul 3, 2012.
KHLow2008 - Thank you for the reply.
Would the car's ignition switch cause the fuel pump not to engage?
The car cranks (spins over) with no problems but will not start - until the fuel pump cycles on, which would be my only concern with replacing the ignition switch.

Tiny
Morkfromork
Jul 3, 2012.
Yes. A faulty ignition switch can result in missing power supply and that would not allow the fuel pump to engage.

The starting position uses another circuit so you caould have the starter spinning but no power is sent to the fuel pump.

You could also have a faulty main or fuel pump relay etc and you should not be replacing components without testing and confirming that it is bad. Try swapping out the fuel pump and main relay with either the A/C clutch or headlight relays to test.

If you have a test light or DVOM, you can use it to perform tests.

Btw did you note if the dash indicators lights stays on while cranking?

KHLow2008
Jul 3, 2012.
Oops I hit the "flag for review" button thinking it was a reply button - sorry.

Thanks again for the reply, I was not aware of the circuitry contained in the ignition switch.

I have checked the dash lights and they do stay on while cranking.

Also I have checked the relays that control the fuel pump, both the "EGI Main" and the "Circuit" relays and they are both good. I replaced them both just to eliminate that variable.

Is it a possibility that it could be the ignition and not necessarily the switch? I only mention because I have heard of others having problems and that being the culprit in some cases.

Thanks for the help and answers you have provided, much appreciated, I have been trying to figure this little ghost problem out for a while and it rarely happens when I have tools handy to diagnose.

Tiny
Morkfromork
Jul 3, 2012.
http://www.2carpros.com/articles/car-cranks-but-wont-start

When engine could not start, you need to find out what is missing. It could be the ignition system such as sparks or the fuel pump. The above link explains what to look for when it fails to start.

KHLow2008
Jul 4, 2012.