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-   -   It cranks, has fuel and pressure and spark, but won't start. (https://www.rx7club.com/3rd-generation-specific-1993-2002-16/cranks-has-fuel-pressure-spark-but-wont-start-646077/)

HHTurboVert 04-24-07 11:32 PM

It cranks, has fuel and pressure and spark, but won't start.
 
Ok so here is the deal, I just swapped a used J-spec in place of a blown A-spec into a 93'. I just finished but the car won't start. The car cranks fine, but there's no combustion.

I've gone through the trouble shooting guide in the FSM, it said to check the following.
1. Crankshaft position sensor
2. Main relay
3. Fuel pump
4. PCME(1H, 1O, 1T, 3I, 4D, 4E, 4G, 4H)
5. Igniter
6. Injector
I've checked all of these already and found no problems.
There is spark and fuel pressure, but I don't think the injectors are pulsing. I've checked every wire at the ECU 1A-4Z with my multimeter and every thing checks out execpt the clutch switch is always at +B(batt voltage, it's supposed to go to less than 1V when depressed). I don't think this would cause the car not to start though right?

I've also jumped the Gnd and TEN pins in the diagnostic connector but there aren't any error codes( there were a few minor ones, but I solved them). I've also jumped f/p and gnd and verified that the fuel pump is working.

I was thinking it could be a bad ground somewhere, but I've check all the easy to access ones, like the one at tha back of the UIM an the one that bolts to the engine below the spark plugs. I also specifically remember tightening down the one on the top of the engine under the UIM.

If anyone can help me solve this issue I would really be grateful. I might even paypal you some money if you solve me problem.

In case the above description of the problem is too convoluted, my engine has spark and fuel pressure, but theres no gas getting into the engine. What can cause this?
Your suggestions and ideas would be appreciated. Thanks

TheCrazyAZN 04-25-07 12:22 AM

Your Fuel Lines hooked up correctly? Feed actually going to Feed, Return Actually going to return etc etc?

12leavu 04-25-07 12:28 AM

mine did about the same thing. it was the main 120 amp fuse under the hood blown.

DriftTrix 04-25-07 02:25 PM

Yeah, I would check the feed and return lines too ^^ good call!

Jay7 Nyc 04-25-07 03:14 PM

Yes it could be the fuel lines return and feed. Also change the fuel filter if seen some completely clogged on 3rd gens from yrs of sitting. Check the plugs see if they're wet, fouled or black. If they are any of the 3 mentioned then clean out the combustion chamber by pulling the EGI relay and crankin the car with only the trailing plugs in place. Then clean the plugs or put new ones in and crank the car with the EGI inplace...

Jay7..

HHTurboVert 04-25-07 07:32 PM

Thanks for the suggestions guys, some good ideas but no cigar. I've already checked to be sure the fuel lines are correct. The car still started until I took the motor out last week, so I don't think its the fuel filter and its not the 120a fuse because all of the other elec. acessories work, and I checked too. Along with every other fuse in the car.

One other clue is that when I turn the ignition key to the on position it sounds like all the relays click on but then one second later click off. Sound familar? Any more ideas? Please keep them coming guys.

HHTurboVert 04-26-07 12:12 AM

Anymore ideas guys?

HHTurboVert 04-26-07 11:07 AM

Does anyone know how I can test to see if the injectors are pulsing without an ocilliscope? Can I use my digital multimeter somehow? I'm going to check to see how the plugs look and then re-check the main relay according to the FSM. I still need more suggestions though. I know someone has had this same issue before, I need more ideas.

Eggie 04-26-07 02:11 PM

Should be able to hear them clicking, especially if you use a mechanic's stethoscope (i.e. piece of hose in your ear). You can also disconnect the harness and test the injectors directly with 9-12VDC. This makes hearing them a lot easier, but it doesn't test if the ECU tries to fire them.

paintballpfl 08-27-07 11:33 PM

I am having the same problem, can any one suggest a diagnostic tree that is a little more helpfull than the FSM? It seems that mazda may have used this material as an advertisement to by "testers" more than a helpfull aid in my oppinion.

mono4lamar 08-28-07 06:23 PM

Take off the upper intake manifold and as said charge each injector with a battery. You will hear and unmistakable click noise. Just make sure you dont have the fuel system primed cause if you hold that injector open it going to obviously disperse the fuel.
Also have you done a compression check yet?

HHTurboVert 12-31-08 02:53 AM

I just realized I never posted how the problem was solved. Turns out, the injectors were pulsing. The engine was horribly flooded. It started using starter fluid.


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