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Does anyone know anything about 2004 Mazda 3s 2.3?
So here what happened, the car had a really rough idle due to # 2 and #3 misfiring, I got new coils for it and it cleared the misfire up but was still idling a little rough, so I went ahead and disconnect the battery for a few hours to clear the PCM, here's where it gets weird I hooked the battery back up and she fires right up no rough idle purring like a kitten.... shut her off and didn't mess with the car for a few days try to start it and nothing as in no fire at all, it sounds like it wants to start but is lacking the juice to burn ... so I take some brake clean and shoot some down the throttle body and crank it over and she fires right up, SO I Replace the fuel pump cause it wasn't firing..new pump and still not firing and I can hear the pump kicking on .. the injectors show to have power but no pulse when using a test light on the hot wire. I can hear the relay click and all the fuses are good. I was told these had a built-in fuel filter in the pump and that's been replaced already and I don't think it's the anti-theft system cause that would kill the cranking part...I plan on checking fuel pressure as soon as I get a chance to pick up the tools for it .... any help is appreciated
OH!! and there are no codes either to even point me any kind of direction ..
Thanks
Well, if she fires up with a squirt of the good stuff, you have a fuel delivery problem. Doesn’t mean it’s the fuel pump necessarily.
I’m not sure how many times you’ve replaced a fuel pump but typically it takes a few cycles to build up fuel pressure in the lines. I would cycle the key about 5 times allowing for the pump to prime and not cranking. Then attempt to start.
To test for injector pulse, you need to attach your test light to battery positive and touch the control wire of the injector. The control wire shouldn’t light until you crank the engine. (Seems unlikely that you won’t have injector pulse given the circumstances)
You are going to need to test for fuel pressure. A new pump doesn’t mean it’s a good pump. Sometimes they wire them incorrectly and the run backwards (DC motors). And sometimes they’re just defective.
Making Pressure Differential Sensors (PDA Sensors) for pressure pulse diagnostics.
Currently servicing Central Texas.
So I tested the fuel pressure and got 50psi at the fuel rail.. I also re-verified spark on all 4 cylinders.. I'm waiting on a compression tester to see what it is on this.. if that checks out ..where else can I look???
I'm not sure what spec is, but 50 PSI is more than enough for this thing to start. :huh: Was the pressure tester connected in-line, or deadheading the pump?
Spark, fuel pressure, injector pulse... This car should start. :silly: I doubt you have a compression problem since it starts and runs with an external fuel source. Are you sure about having injector pulse? Because that'd neatly explain your symptoms.
Tyler wrote: 50 PSI is more than enough for this thing to start.
I doubt you have a compression problem since it starts and runs with an external fuel source.
Are you sure about having injector pulse? Because that'd neatly explain your symptoms.
I was just getting ready to say that.. I took the whole fuel rail out place some small bowls under the injectors and cranked the engine a few times... it looks like I have serious moisture problem in my fuel.. guess it's time to flush the tank and try some clean gas..
Noah called it a mile away. I thought about suggesting a fuel quality issue? But it didn't make sense to me that the fuel would suddenly 'go bad' while sitting for a few days. That's what I get for thinking. :silly:
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