Miata has new fuel pump, new injectors, will start on starte r fluid in the air intake but will not run on own

My first post, hope I am doing this right.
First, I aquired a miata that has sat for 2 years. I have drained the fuel, replaced the fuel pump, replaced the injectors, checked the fuel filter, checked the fuel pump relay (fuel pump is now working). The car will almost start after sitting for a bit and then die. I can get it to run with starter fluid in the intake and I can keep it running by adding a shot every few seconds, but it will not run on it’s own.
Any ideas? The MAF should not cause a problem until it is running, the computer appears to work as the check engine, et al light up with key in run. cylinders have fuel and spark… becoming the stumped chump.

If all the cylinders have fuel and spark it would be running ok. You know its not a spark or timing problem b/c it runs on starter spray into the air intake. So it must be a fuel problem. Check for stored diagnostic codes then measure the rail fuel pressure is where I’d start. Post the model year and engine for best help here. If you feel lucky, and this car uses a rail mounted fuel pressure regulator, remove its vacuum hose and see if there’s any fuel inside. If there is the fpr needs to be replaced.

Sorry, I put the 2001 Mazda Miata in model and make, but it did not show up. Next step is to measure the pressure.


The spec I’m seeing for the 1.8L engine is 53-61 psi w/36 psi hold pressure. Safety is paramount when working w/fuel. All fuel-safety practices apply. For diy’ers willing to take the risk, best to do this sort of work outside away from buildings and have a big fire extinguisher nearby and ready to go. Keep anything and everybody that has a spark or flame completely out of the area.

Are you trying to start the engine with the intake hose disconnected? The intake hose and MAF must be in place for the engine to run.

Generally the hose is connected so it will have airflow over the MAF. The exception is when I used starter fluid and I disconnect post MAF so the starter fluid does not ruin the MAF.

Thanks for the spec, and I do follow safety… I can imaging Tom M making a comment about the “Fire Safety Engineer” Ben Liddup -(been lit up).

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I don’t know how to check filter without a pressure gage. But in any event the filter could be the problem as the car set for awhile. Replacing it would be a good idea in any event.

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How did you determine that fuel is getting to the cylinders? If it’s just “It must be getting to the cylinders because I replaced all these parts,” then you don’t know for sure that it’s getting there. There are some parts you haven’t replaced, and the ones you have could be defective out of the box.

TCmichnorth, I have checked the filter, it had been replaced just before the car was set up and is still pretty clean as it had little use.

Shadowfax, I checked by removing the plugs as well as after trying to start it, then let it sit for about 30 minutes, it will almost start (run for a second or two). I think I need to check the fuel pressure today. Just because it is getting fuel does not mean it is getting enough or too much.