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This is just something that bothers me.
When I start it it seems to take a while 3-4 seconds of cranking before it starts. Battery, plugs, wires, rotor/cap are all new. It just seems to crank longer than most other cars that I've driven. I was thinking maybe taking starter apart and seeing if any parts need replacing.
I noticed on warmer days it will usually start right up or when I drove it 2-3 hours ago.

mitmaks wrote:This is just something that bothers me.
When I start it it seems to take a while 3-4 seconds of cranking before it starts. Battery, plugs, wires, rotor/cap are all new. It just seems to crank longer than most other cars that I've driven. I was thinking maybe taking starter apart and seeing if any parts need replacing.
I noticed on warmer days it will usually start right up or when I drove it 2-3 hours ago.

You'll more likely want to check fuel pressure... You'll need a gauge hooked up to the car.. See if fuel pressure is bleeding off after you shut down the car... Also see how long its taking for it to build up afterwards...

Crazy is right... try pumping the throttle three times, for 2 seconds each, prior to cold start. Simple, easy test!!

MrMazda92 wrote:Crazy is right... try pumping the throttle three times, for 2 seconds each, prior to cold start. Simple, easy test!!

Pumping the throttle isn't a good test with a fuel injected car... It might help, but it wont tell you for sure that its a fuel pump problem...

Holding the throttle down prior to start floods the engine... Why wouldn't priming the injectors slightly be a decent test? Not very specific, but it'd certainly point you towards fueling. :/

My '92 cranks for about 1-2 seconds when cold, my '93 is 4-5

how does throttle position affect the pump? When the key is on but the engine's not running the ECU (I think) is not sending any signal to the injectors. Key on starts the pump, which pumps until the pressure in the rail is up and then cuts out.

If pressure is low it's likely because the pressure sensor is out of spec and cutting the pump early.

Just a guess. I don't have intimate knowledge of the fuel system controls.

I just know that when I have had no starts in the past(long cranking, or stalling as soon as the engine starts), that flooring the throttle 2-3 times always got it going.

Not exactly a scientific approach, but it certainly worked.

I was told it might be due to forcefully sold ethanol gas we have to buy.

dirty fuel filter?

Changed fuel filter ~100K, has ~120K miles on it now. Also checked fuel pressure a few months ago and it was fine.

How good is your battery. My engine cranks like 40 and fires up right away. I have a real good expensive battery.

Replaced in the spring.

mitmaks wrote:Changed fuel filter ~100K, has ~120K miles on it now. Also checked fuel pressure a few months ago and it was fine.

You need to leave the fuel pressure gauge hooked up at minimum 30min to an hour with out touching the car... All though if I was doing this to my car at home, I would leave the gauge hooked up over night and watch what the fuel pressure is/doing during the long cranking...

Since your problem is only on start up you should have good fuel pressure once the car is running....

What I suspect you'll find is that fuel pressure over night is bleeding off to almost 0... The older mazda's I believe don't prime the pump during key on... (my old KL swapped 323 didn't, and I don't recall my gf's old stock mx3 priming the pump either).... With no pressure in the system it takes a bit for enough fuel pressure to build up during cranking... This happens because you have injectors spraying fuel at the same time as the pump is trying to build pressure... Pumping the throttle during cranking makes the computer increase the injector timing... That just helps get enough fuel to start up sooner...

If fuel pressure is bleeding off while the car sits you either have a problem with the check valve in the fuel pump its self being bad, or the fuel pressure regulator has a week spring/leaking internally....

MrMazda92 wrote:Holding the throttle down prior to start floods the engine... Why wouldn't priming the injectors slightly be a decent test? Not very specific, but it'd certainly point you towards fueling. :/

My '92 cranks for about 1-2 seconds when cold, my '93 is 4-5

Try holding your foot to the floor on a ford/gm or even a later model mazda... It doesn't flood the car.. Most cars actually go into whats called "clear flood mode".. They shut the fuel injectors off completely...

pumping the peddle just tells the computer to increase injector on time.. this allows for more fuel and makes the car start up faster... not all cars will do this though... This only tells you that its a possible fuel related problem...

Well that explains a bit more I stumbled onto it as a "Well, maybe this'll work" method.

crazycanadian wrote:What I suspect you'll find is that fuel pressure over night is bleeding off to almost 0.

Could be as simple as the fuel cap? Filler neck leaking too maybe? I had to replace mine because it was rusted and leaking (bad spot for snow and salt to sit where it was ) Or maybe just the seal around the fuel pump/sending unit is gone?

crazycanadian wrote: Try holding your foot to the floor on a ford/gm or even a later model mazda... It doesn't flood the car.. Most cars actually go into whats called "clear flood mode".. They shut the fuel injectors off completely...

My Rx8 has that feature (obviously), but there's a better deflood method that I came across and worked very well where the pedal didn't

crazycanadian wrote:pumping the peddle just tells the computer to increase injector on time.. this allows for more fuel and makes the car start up faster... not all cars will do this though...

That would only be during cranking, and would have no effect if it was done prior.