Fuel pump question???
 

Gotta quick question about the same thing... the guy that I bought mine from replaced the sending unit an pump an now the pumps bad again can I just change out the pump instead of replacing everything or are they all one unit? an what brand should I replace it with ?

I was only getting 23psi w/ a year old pump

sorry... its a 1993 W motor vortec

RE: Fuel pump question???
 

You should be able to replace just the pump on this model. Get a good brand of pump and you should not have to replace it again so quickly.

RE: Fuel pump question???
 

Okay I can get a Bosch Lifetime warrenty pump from advance for $96.99

or a AC Delco Lifetime from the dealership for $156.99

so are these worth the extra money an actually goin to the dealership?!

RE: Fuel pump question???
 

Work the dealer over on the price.

On RockAuto.com:
The AC Delco pump (# EP381) sells for $89.89 and requires the strainer (AC Delco # TS7) is an additional $6.50.
The OE Delphi pump (# FE0114) sells for $74.79 and also requires the strainer (AC Delco # TS7) for $6.50 additional.

The only good thing I can see about the Bosch pump is that it includes a new wiring harness with the pump. I am not sure if the AC Delco or Delphi units include the wiring harness.

And yes, I would definitely rather pay a bit more for an AC Delco or Delphi unit than to have to do this job over again in short order due to using aftermarket.

RE: Fuel pump question???
 

okay the dealer had to get it from another place it will be in theis afternoon an i'll pick it up in the morning would they even make the effort of matching prices? an should I replace the wiring while i'm at it? I think thats like $9.49 at advance

RE: Fuel pump question???
 

I would at least have the wiring on hand.

And they should make an effort to come down on the price a bit. My dealership parts counter guys expect me to haggle with them on price. When I purchased the MFI spider for my old 2000 Bravada, they quoted me close to $400 for the spider. I paid under $300 for it because I told them I would just buy it from someplace else if they could not do any better. Since you have already ordered it, it may be more difficult... But it is worth trying!

The OE part number for the pump is 25163473 and lists on GMPartsDirect.com for $81.33. Print that off and show it to them. That is probably below their cost on it by the time you add S&H, but you have room to work with them. I would think you should be able to get them down under $100.

RE: Fuel pump question???
 

wow thats crazy I could have that part overnighted for $40 less than goin to the dealership I wish I woulda seen this earlier we need it in the morning to put it all back together though this sucks but thanks for all the info!

RE: Fuel pump question???
 

Okay... got the pump replaced... Now i'm getting 43lbs of fuel pressure but still wont start where do I go from here???

RE: Fuel pump question???
 

okay poured fuel down the TB today and it fired up.... ran for aboiut five mins an shut it off an tried to restart and would just crank... Relieved the pressure once an it fired back up w/ out gas in the TB shut it back off an tried again an it would just crank an crank wont start any ideas or help!?!?! Please!

thanks

RE: Fuel pump question???
 

43PSI is too low. To see if you installed a bad fuel pump (what brand did you buy?), you need to remove the fuel filter and adapt your fuel pressure gauge to the line that runs to the pump. Check the pressure right there. You should see at least 60PSI.

RE: Fuel pump question???
 

its an ac delco pump

RE: Fuel pump question???
 

not to sound foolish but sometimes the simple things get us, look through your rear wheel well (this happened to me on my 94 after replacing the fuel pump) and look at your fuel lines i was sloppy when putting the tank back in and kinked one of the nylon lines which was not allowing enough fuel flow was a very simple fix and easily seen from looking through the wheel well, wont hurt to take a look just to be safe.

RE: Fuel pump question???
 

will check that right now changing the fuel filter also

RE: Fuel pump question???
 

replaced the filter an checked the lines... Still nothing when the pump is running though its really loud almost like a faint siren or horn this I know this isnt normal anyone had this happen before?

RE: Fuel pump question???
 

I guess you missed the rest of my post when you got to the first question.

RE: Fuel pump question???
 

what was that? im lost sorry!

RE: Fuel pump question???
 

is it supposed to be that loud or could it be a defective pump?

RE: Fuel pump question???
 

About how loud a pump should be, there is no set sound level for a fuel pump in these vehicles. Some are louder than others. Some are designed to be more quiet than others. The original design was a rotary vane style impeller and some aftermarket pumps changed to a turbine style impeller which is much quieter and should be more robust, but these are the pumps that most often fail.

So to reiterate, to determine if the pump is what is causing the low fuel pressure condition, you really need to test the pump discharge pressure at the fuel pump.

RE: Fuel pump question???
 

okay took it down to the local garage... When cranking have 45-46 psi an 50 when started they are now telling me its the injector that needs to be replaced

RE: Fuel pump question???
 

Are they going to guarantee that will fix your problem. If you still have not tested the pump discharge pressure at the fuel filter, you are subject to speculation.

How did they come to find that the injector is at fault? Did you ask?

RE: Fuel pump question???
 

okay dumb question but is the cmfi trhe same as the cpi? in the chiltons book I was tryin to look up fuel pressure numbers an the cmfi is callin from 58-64 psi is that what I should be getting at the rail? also what adaptors do I need to test it at the filter? The shop couldnt guarentee that thats gonan fix the problem so I brought it home.. Took the plenum off an everything looks good an new under there so now its leading me back to the fuel pump, I check all the lines for kinks or anything ordinary everything looks good! an it has a new filter. So I called the dealership an a another new pump is on its way will be in tomm am but now they want the Vin number an milege of the vehicle is this normal?

thanks alot for all the help!!!

RE: Fuel pump question???
 

The fuel pressure requirements between the CPI motor that is in your truck and the newer SCFI is the same. You need in excess of 52psi for proper opening of the poppet nozzles that are used.

RE: Fuel pump question???
 

Yes, CMFI = CPI

RE: Fuel pump question???
 

so it wasnt normal for when I turn the key on it went to 45 an after the pump shut off it dropped to 20ish psi?

RE: Fuel pump question???
 

No, not at all normal.

RE: Fuel pump question???
 

would that be the pump faulty then? or is there another place that it can lose pressure like that?

RE: Fuel pump question???
 

Um, someone else can better answer that, but there are 2 places that could cause leakdown: one is the fuel pressure regulator, the other the fuel pump.

I can't remember what test tells you which is bad, though...:eek:

RE: Fuel pump question???
 

Run down through the test in the DIY section. Even though I think I wrote it up for the SCFI motors, the components are very similar and the pressures are the same. The diagnostic chart that I posted will point you at the appropriate component at fault.