2005 Mazda 3 Won't Start But Cranks **PLEASE HELP**

[GarrettMazda]

Hello there,
I have been running into a problem with my 2005 Automatic Mazda 3 Hatchback it cranks but doesn't have that oomf to start, ive been hitting the gas pedal while attempting to start. I recently just had a tune up done on her, i've done almost everything i've come across on the internet. I made sure there was fuel going through to the fuel pump, spark plugs were just replaced, tried to boost it, charged the battery and nothing seems to work. It had this exact problem a month ago but not this bad. When I got it started a month ago I hit the gas while someone was banging on the fuel tank under the car(I came across a forum that said this might work) it did work for the first 3 times but not now. When I did get it started I let it run for 20 minutes and then another 15 with AC on to try and reset the computer. It fixed it for about a week, it started like she was new. It all got worse when it stalled when I came to a complete stop, the RPM's just went lower and lower until she quit. :(((((

When I try and start it wants to fire but doesnt (the rpm goes up and then goes right down to 0)
Do you guys have any suggestions that might work? This is very fustrating.
Car has 131 000 kilometres.
There is half a tank of premium fuel in her aswell.

[nigvlb_]

Hello there,
I have been running into a problem with my 2005 Automatic Mazda 3 Hatchback it cranks but doesn't have that oomf to start, ive been hitting the gas pedal while attempting to start. I recently just had a tune up done on her, i've done almost everything i've come across on the internet. I made sure there was fuel going through to the fuel pump, spark plugs were just replaced, tried to boost it, charged the battery and nothing seems to work. It had this exact problem a month ago but not this bad. When I got it started a month ago I hit the gas while someone was banging on the fuel tank under the car(I came across a forum that said this might work) it did work for the first 3 times but not now. When I did get it started I let it run for 20 minutes and then another 15 with AC on to try and reset the computer. It fixed it for about a week, it started like she was new. It all got worse when it stalled when I came to a complete stop, the RPM's just went lower and lower until she quit. :(((((

When I try and start it wants to fire but doesnt (the rpm goes up and then goes right down to 0)
Do you guys have any suggestions that might work? This is very fustrating.
Car has 131 000 kilometres.
There is half a tank of premium fuel in her aswell.
starter relay? check all wiring.

[dentinger]

Then it wouldn't crank at all.

So, we know you have power to the starter, it cranks just fine.

So, you either have no spark (or weak spark), or no fuel (or bad fuel)

Judging by what you be described, you have a fuel related problem. You can try opening up the air filter box, and spraying throttle body cleaner or brake clean down the tube towards the intake, while someone else cranks it.
If it fires up, you have a good starting point.

You can also double check the plugs, make sure they aren't fouled.

One more thing, you can try clear flooding it. Gas pedal to the floor, and crank it for 15-20 seconds. Don't hold it forever, you'll cook the main starter power wire.

Source: I'm a mechanic

[dentinger]

Oh, you can also check for fuel pressure. you might have a schreader valve on your fuel rail or near by (on the fuel line). Key on, depress the valve (exactly like a tire valve), and see if fuel comes out. If it sprays out with force, you know the fuel pump is most likely doing its job. If nothing really sprays out, you know it's not

[dentinger]

Being that the mazda3 is technically a Ford vehicle, do they have an inertia switch like most Ford's do?

[shiftyy]

Bump this thread...

Ran into this exact problem yesterday, car cranks like hell and even fires once or twice then the started disengages and RPM's drop to 0. It stalled twice after coming down from 3000RPM the day before, and they just dropped to 0 again. Got a laundry list of stuff to try such as a hard reset on the computer, cleaning the MAF and IAC/TB.

Is there anything else I can try? Battery is solid, you can hear the fuel pump priming the engine for the next start, and I don't think the air intake is blocked although I will have to check today.

Thoughts?

[Booter22]

GarrettMazda did you have any issues before? how recent was the tune up done? what did they do? what parts did they use? oem or aftermarket.

[shiftyy]

UPDATE: I found the source of the problem. It's a dirty MAF sensor. Took me 15 minutes to fix with a couple of bottles of cleaner for the MAF and the throttle body (TB). I apologize for no pics, may update later.

Step 0: Disconnect BOTH the positive (+) and negative (-) terminals of the battery. Then TIE THEM TOGETHER for the duration of this repair. This will perform a hard-reset on the ECU, which will allow it to reprogram itself from ground-zero. If you don't do this, you could short something or screw up the position sensor on the throttle body. That's NO BUENO.

Step 1: Unscrew the two screws holding the MAF in place. Disconnect the harness. Put the MAF on a shop cloth or rag, something relatively clean.

Step 2: Spray the amber-coloured bulb with MAF cleaner (http://www.canadiantire.ca/en/pdp/crc-sensorkleen-mass-air-flow-sensor-cleaner-0381704p.html#srp) and the two wires down the hollow shaft area of the sensor. Let the cleaner soak if all the dirt doesnt come off at first. Repeat until bulb is clear. You can't really see the wires, but spray them the same number of times as the bulb to be sure. DON'T TOUCH/DAMAGE the wires or bulb. That's a new sensor. About $75 on Amazon I think.

Step 3: Unclip the top of the air box, inspect filter. If it's dirty, replace it. It'll help with airflow.

Step 4: There's a couple of harness plugs that you should disconnect at this time to make it easy to take the intake boot and air box out of the way. It's pretty obvious, so unplug those.

Step 5: Unscrew the pipe clamp at the throttle body end of the intake boot. Pull boot and air box top assembly off as a whole. No need to separate these two pieces.

Step 6: Disconnect all harness pieces from the throttle body BUT LEAVE THE WATER HOSES. That's a whole other demon you don't want to mess with.

Step 7: Use a deep socket (8mm or 10mm.... I forget) (deep for clearance, though short ones do work) and remove the 4 bolts holding the TB in.

Step 8: Pull the TB back, rest it on whatever is under it but careful not to damage the water hoses. Use TB cleaner (http://www.canadiantire.ca/en/pdp/crc-throttle-body-kleen-air-intake-cleaner-0380781p.html) and spray both sides of the butterfly valve to soak, then spray again to remove debris. I sprayed until the excess liquid running off the engine side (by far much dirtier) ran clear as it dripped away. I figured that's about as good as it gets.

Step 9: Make sure the TB and MAF sensor are dry, reassemble everything in the reverse-order of how you took it apart. Connect the battery again, and start the car. It'll idle funny for about a day, then the ECU will begin to re-program itself and learn to run smoothly. I think it stalled once (doing the funny RPM drop thing) on the way home, but it's been running super well ever since. No start up struggles, no pick up lag.

I'm on day 2 of this fix, and it's running even smoother than it did previous to it stalling like previously described.

Hopefully this helps!