Did The Parts Jockey Give Me The Right Part?

[LSVLance]

I asked for a fuel pump assembly for a 2003 Tahoe, 4x4 with a 5.3 Flex Fuel "Z" code engine

He had an Airtex and a Delphi, I asked for the Delphi.

I did quite a bit of online shopping before deciding to buy it locally, and EVERY place I looked had different part numbers for the "T" code engines and the "Z" code engines (like I have).

After I got the part home, I decided to google the part number on the box. Ever result pointed towards a fuel pump assembly for a "T" code engine.

Here's what the label on the box says:

Delphi
C# FG0324
IO# FG0324-11B1 then in smaller numbers beside it 16108
QTY#1
Module
Made in the USA
UPC 689604084274


I have two concerns and I hope a tech on here can help me settle them. First, I want to make sure I have the right part for the car before I start pulling the tank on Saturday morning. Second, if this is the right part, I'd like to buy it online for the $190 I found it for instead of the $290 I paid O'Reilly for it.

Does anyone have any insight they can shed on my dilemma?

Thanks,
Lance

PS, Part of my concern and why I decided to buy it locally is they have changed the electrical connection on these and I wanted to make sure I had the new one to put on the vehicle side of the connection...which this one DID come with.

 

[Sepiroth]

I forget the reason why the pumps have different numbers, but, you got the wrong pump.

 

[LSVLance]

I even called back to Oreillys, got a different guy and had him look up the fuel pump assembly from scratch. He even had me read the VIN # off to him. And their computer came back with the same part # again.

Something here stinks...

What is the difference in the fuel pumps between the "Z" code and "T" code engines anyway? Anything?

 

[FATHERFORD]

Yes,

For one I'm sure it's a bigger pump, two the seals on it are probably a little bit different to run e-85 and gas.

That's just a guess, but I'm sure the correct answer.

 

[LSVLance]

Let me ask this....if I don't ever plan on running E85 in it, can I get away with running this pump I currently have?

 

[FATHERFORD]

Not sure if the hook ups are the same.

Do these year models have returnless fuel systems? Is the voltage always the same or does the computer vary the voltage for fuel output?

 

[LSVLance]

The new pump came with a new pigtail to connect to the factory harness, so electrical wise, it'll be fine. And I'm assuming the plumbing of the fuel lines will be the same as well. This is the correct pump for this vehicle, just for the one with the T code engine, not the Z code.

I just talked to a mechanic that replaces a lot of these and he says his parts guys don't even ever ask if it's a T code or Z code vehicle, he just gives them the year make and model and they send a pump out. He also says that Oreilly's computers are off on all kinds of stuff, so this didn't surprise him at all.

He told me that as long as I don't run E85 in it, it should be fine.

 

[rob0014]

As far as the seals, all fuel system components have had to be ethanol-compatible since the early 1990s when the 10% ethanol blends came out.

All our gas around here (Chicago area) has had 10% alcohol in it for many years now.

The E85 pump is probably slightly larger since E85 gives fewer miles per gallon, so the pump has to move a little more fuel for the same amount of miles driven as it would on gasoline.

There are stories online of people running non flex-fuel vehicles on E85 with no major problems (although they get less power with a non flex-fuel vehicle), so I would think that the fuel pump isn't a problem. One thing I read was that a side-effect of running E85 is that the pump and sender stay cleaner than than they would in gasoline.

 

[FATHERFORD]

As far as the seals, all fuel system components have had to be ethanol-compatible since the early 1990s when the 10% ethanol blends came out.

Walbro will NOT warranty or guarantee non pump damage when using E-85.

The E85 pump is probably slightly larger since E85 gives fewer miles per gallon, so the pump has to move a little more fuel for the same amount of miles driven as it would on gasoline.

E-85 takes minimum 30% more fuel. So either the fuel pump was big enough from the start, or they had to increase it. I do know the flex fuel engines have bigger injectors then non flex fuel engines.

Unless the engine can compensate for the increase in fuel, it will burn up the engine going lean.

 

[rob0014]

Walbro will NOT warranty or guarantee non pump damage when using E-85.

True enough. They're not in the business of warrantying engines. My answer was meant to convey just that the materials the pumps and seals are made of won't fall apart in ethanol.

E-85 takes minimum 30% more fuel. So either the fuel pump was big enough from the start, or they had to increase it. I do know the flex fuel engines have bigger injectors then non flex fuel engines.

Very good point. Bigger injectors are going to flow more fuel.

Unless the engine can compensate for the increase in fuel, it will burn up the engine going lean.

The PCM would detect the lean condition with the O2 sensors, but it wouldn't be able to compensate for it if the fuel pump was already flowing its maximum.

The mechanics who are putting in the wrong pump are gambling on their customers not pulling any heavy trailers up hills - which is where you'd need the full capacity of the fuel pump. Even if there's no engine damage you might not be able to make it up the hill with a full load or a trailer. That would suck.

I am the kind of person who likes to have everything overbuilt - I like wide margins of safety. So, I have agree.

If it were my vehicle, I'd want the right fuel pump in it. Especially since there's not a huge cost difference to get the right pump.

If you just drive around town at low speeds, you could get away with the wrong pump. I like to accelerate really hard on the expressway though, so I probably couldn't.

 

[LSVLance]

I guess I should post an update. I ended up buying a Carter flex fuel capable fuel pump from Napa for about $250 and taking the non Flex Fuel Delphi pump back to OReilly. I looked at the screen on the OReilly computer when returning it and it very clearly showed their AirTex pump as the only one they had for the flex fuel option and the Delphi unit the guy sold me was clearly NOT for my Tahoe. They just didn't want to loose the sale once I told them I wouldn't buy an AirTex brand.

Well, it cost them as I'll remember that with every part purchase I make from now on.

The pumps had all of the same connections and looked compatible but were completely different. The Carter was made out of steel, had the sending unit encased inside it and the seal was made out of a butyl type material, not rubber. The Delphi was made out of plastic, had the sending unit exposed outside the unit and had a rubber seal.

It took me about 2.5 hours to swap it out, not that difficult of a job...but would have been easier had I done it here at work on the lift instead of at home on jack stands. The hardest part was getting the back part of the tank low enough to get my hands up on top of the tank to get the fuel lines loose...before the tank could slide back far enough to drop the front part below the cross member.

Thankfully, there was only about 3 gallons of gas in it at the time (gauge said there was a 1\4 tank). Had it been half full or more...would have been a ROYAL PITA to do.

 

[Sepiroth]

I am glad everything worked out for you.