It won't start.
 

Trying to get the miata started after installing the Pierburg pump. I disconnected the injector relay while it was idling to depressurize the system. Once it stalled I hooked the plug back up.

I drained all the gas from the car and hooked up the pump. I put 2 gallons into the tank. Primed the system for a total of maybe 2 minutes, and can feel the fuel pumping through the lines under the hood.

The pumps "whur" when priming, I'm assuming that's how it's supposed to sound. Checked all fuses, thought maybe one was blown, they look good.

I just pulled an injector and it didn't smell like gas. So, is this an injector problem? I've been cranking and cranking so the injectors should be wet? Injector relay?

fuses "look" good? but does that mean they ARE good? Test em out first

Maybe the pump is running "reverse"?

Hell, maybe. I don't really know what that means :)

I could post a pic of the Pierburg. Maybe it's in "backwards" you're saying?

Just comfirmed 12 volts at the injector. How can I do a one person spark test?

does this help?

https://www.miataturbo.net/forums/at...5&d=1163312208

Attachment 2525

Almost every single time i have had a problem like this, it turned out to be something I messed with and didnt put back together right ... namely stuff like leaving the cas plug out, or something like that. If you only messed with the pump and its turning on, make sure you have it pumping in the right direction. Lol i know it sounds simple but stuff like that is easy to do.

any word?

gosh darn that pic looks like a pain in the BOOOTY!

Are you sure you don't have the polarity of the connections reversed? Is the install identical to the picture? Sort of looks like the one here, but reversed: http://www.rev2red.com/images/cars/begi4install.pdf

it is the same picture but i flipped it since when I got up under the car I noicted the PPF isn't on the outside. and above picture is how it looks when you crawl under the car to install it.

double checking polarity makes sense. if you installed it correctly but it's flowing back into the tank, you wont have any fuel at the rail.

Sorry fellas, I have two threads about the same problem. I'll continue here, and edit the other to direct here. Thanks for the help!!

I posted pics in the other thread, which I'll link to here.

Pics of the installed (hopefully backwards) Pump.

https://www.miataturbo.net/forums/sh...0&postcount=10
https://www.miataturbo.net/forums/sh...1&postcount=11

install is correct. pull the return at the engine bay and verify it dumps fuel. if not, try reversing the power leads on the pump and see if that doesnt fix it.

Pulled. Plenty of fuel there. Battery is getting low, going to charge w/ another vehicle.

Tried a spark test. Holding the plug close to the head to verify spark. Got a yellow spark. I know it's supposted to be a strong blue, but the low battery explains that, and it was fully charged when I started. Still, will try jumping it.

The INJ relay/fuse under the hood. Any way to test it? I have a voltmeter. Seems the pumps are working and there is spark present. Switched out the engine fuse under the dash even though it was good.

Double checked it all again. The power/ground to the Pierburg is good, and it's spliced into the blue/red power wire at the stock pump. Looked over the bay for obvious screw ups couldn't see any.

Just so I feel better, the air introduced into the fuel lines just pumps through the lines and back into the tank yes? No problem there?

The pump is purchased used from Joel "IntrnlStorm" so I'm sure it works fine. What the shiz am I forgetting......

Correct on the first item. What else did you do?

OK, some good info. Charged battery up with another vehicle.

Jumped GND and FP under the hood, turned key to power the pumps. Checked the voltage at the Pierburg, it was low. Checked voltage at the connection to the stock pump wire and it was 8.8V. Disconnected the Pierburg power wire and checked again, it was 10.8V.

Left the Pierburg power wire unhooked and it started. Power wire back on, does not start.

So, either the power/ground connections, fuel hose connections, or bad pump, right?

The ground was connected to the pump when I got it. It's got a "melt-type shrink plastic" coating covering the connection, but it's solid. The ground connects to the ground already present near the pump with the bolt that's there. I cleaned the connection before install.

I think the fuel lines are correct, I posted them earlier today, #11. B-money confirmed correct install.

I also think the pump is good as Joel sold me other parts that work fine, and he pulled the pump off his car when it was working fine, plus there is fuel in the return under the hood, plus I trust Joel. But, I can't be positive though.



EDIT: Just thinking the whole thing over, I'm thinking it's the connection at the power-in at the Peirburg. I didn't clean it like I thought to do. I Think that would cause voltage to drop, but don't know if it would prevent starting. Back to the garage..

The voltage shouldn't be that low at the pump no matter what. Sounds like a bad connection or relay contact getting back to the OEM pump or a bad ground, maybe originating at the battery or its' ground to the chassis.

Redid the connection at the pump, no help.

Did a test. Unhooked the power to the Pierburg. Started the car. Powered the Pierburg and the car died immediately. :ugh2:

OG: Tested the stock pump voltage while the car was idling, it was 13 and change. I figure it's recharging the battery, but the voltage there (car running) seems fine.

That's where it should be, I misunderstood earlier post. Check the Pierburg by running a separate line before removing it.

I guess I don't fully comprehend how the Pierburg pump works. If the pump is wired directly from the battery will it be pumping constantly? What I'm asking is in the stock setup, does the pump get a regulated or pulsed voltage in order to pump the correct amount of fuel, or does the voltage not matter and the fuel gets regulated by pressure or (?)

So to test, I should start it, then power the Pierburg directly from the battery?

Check this, post 7.

http://forum.miata.net/vb/showthread...light=Pierburg