New fuel pump is getting power but won't prime or run

[02FRTJ]

This is the second Delphi fuel pump Summit Racing has sent me. All was well with this replacement one for a few days and then it sat for a week and now it won't prime. I verified power and ground are present for the 1.5 seconds upon key on. Fuel gauge works fine.

Before I go through the process of yanking another fuel pump out, is there anything else that could possibly create a situation where the pump won't prime or operate even with power? It fired up fine with a spray of starting fluid. So everything on the ignition side is fine.

Everything seems to indicate the pump but what are the odds of getting two defective units in a row?


edit: The power and ground were present at the pump connector. So if it is a wiring problem, it would have to be in the Delphi pump pigtail.

 

[ItchyDong]

Be damn sure the 12 volts you’re getting is carrying sufficient amperage by testing with an incandescent test light. Preferably, you’d test with a headlight that draws about 4 amps. More than likely, you are. But, I’ve been burned in the past. All but one strand of wire can be broken and you’ll read 12 volts on your meter. However, that one strand can’t carry the required amperage.

The same test light test should be used for testing a ground for the exact same reasons. Always load your powers and grounds.

What’s the resistance of the fuel pump?

Edit: never mind. I didn’t catch the fact that it starts up and runs with starter fluid. That would most likely rule out a power or ground issue being that the prime uses the same wiring.

 

[02FRTJ]

I hooked up a 51w halogen headlamp bulb to the pump connector and it glowed bright during the priming sequence. So circuit integrity is fine.

 

[02FRTJ]

I ohmed out the pump and it is showing 20.0-20.2 ohms. And that is through the power and ground pins of the pump.

 

[Moglocker]

I ohmed out the pump and it is showing 20.0-20.2 ohms. And that is through the power and ground pins of the pump.

Looks like summit got a bad batch of pumps,I bought my Delphi at Napa a few years ago.

 

[02FRTJ]

Is there a better aftermarket option than the Delphi?

 

[macleanflood]

I put a Brute Power in my 97 from Rock Auto. Almost the cheapest one I could buy. Been almost a year and a trip from Oregon to the Rubicon Trail and back and lots of miles in-between.

-Mac

 

[B1Toad]

If you have the time and patience you can buy the original Bosch pump and install it into your housing assembly. Somewhere on here there's a thread on exactly how to do it. Amazon has the filter screen for the bottom, I don't remember where I got the pump but I'm sure I have the receipt in my file. It's been perfect for a couple years now,

 

[02FRTJ]

Unfortunately the original pump is gone. It's looking like I should have just kept it and rebuilt it.

 

[B1Toad]

Unfortunately the original pump is gone. It's looking like I should have just kept it and rebuilt it.

Maybe you can put a Bosch in the Delphi assembly? Or pick up an OEM from a salvage yard and rebuild it while you keep running on free Delphi warranty replacements?

 

[02FRTJ]

There are a few "New - Old Stock" OEM fuel pumps on eBay. When were these last manufactured? What are the chances these are legit?

 

[ItchyDong]

There are a few "New - Old Stock" OEM fuel pumps on eBay. When were these last manufactured? What are the chances these are legit?

I wouldn’t trust a thing from Ebay. So many fakes out there now days.

 

[ItchyDong]

I ohmed out the pump and it is showing 20.0-20.2 ohms. And that is through the power and ground pins of the pump.

20 ohms seems crazy high

 

[02FRTJ]

20 ohms seems crazy high

I couldn't find any numbers on what it should be. Just what the fuel level indicator range is in ohms.

 

[macleanflood]

According to Google AI a working fuel pump should be between.5 and 2 ohms. Reminds me I should baseline mine for a reference point should I have issues later.

And if you get a warranty replacement test it before installation.

-Mac

 

[ColoJeep]

For what it's worth , I put a Airtex fuel pump in my 99 in 2012 , still works fine.

 

[02FRTJ]

I spoke with Delphi and they couldn't give me any resistance numbers for the pump itself.

Nevertheless, I purchased another one locally from an auto parts store. It primed and fired right up. The other pump (the replacement to the first dead one) wouldn't do anything even with 12v being supplied directly to it.

Hopefully third time is the charm. Getting tired of dropping the tank.

 

[macleanflood]

Getting tired of dropping the tank.

I've just embraced it. I schedule mine monthly. Of course once I decided it was going to be that frequent I've only dropped it one more time to chop an inch off the skid.

-Mac

 

[Moglocker]

I spoke with Delphi and they couldn't give me any resistance numbers for the pump itself.

Nevertheless, I purchased another one locally from an auto parts store. It primed and fired right up. The other pump (the replacement to the first dead one) wouldn't do anything even with 12v being supplied directly to it.

Hopefully third time is the charm. Getting tired of dropping the tank.

 

[macleanflood]

Fewer things ward off ever having issues again with a fuel pump like an access hatch or on rail fuel pressure gauge.

-Mac