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TaKid455
08-10-2012, 10:08 AM
Looking at a 4th gen that is stated to have a bad fuel pump. Mileage is low <50k. told car runs when fuel is poured in intake. <--seems odd to do on a LS1 motor.

just seeing if this is an issue w/ 4th gens. Dont ind changing pump if that is it, but want to make sure is not something greater.

LTb1ow
08-10-2012, 10:25 AM
Could be a shot pump, or just bad fuel pump relay, wiring, or a theft deterrent system.

Really need more info on the situation, what was tested, and what symptoms its throwing. Otherwise, a fuel pump swap is lengthy only in the steps to get to the pump, the switch itself is easy. Basically need to drop the rear end, drop muffler, drop fuel tank, and then swap pumps. Much easier on an LS1 with the plastic fill neck.

richduty455
08-10-2012, 10:40 AM
unless it a car that you're eh about.....cut out an access panel in the back hatch area.....easy peasy

MyFirstZ
08-10-2012, 10:52 AM
Il be doing the access panel when the time comes for mine

Check fuel pressure when you cycle the key and listen for the pump as well to see if it is turning on.

WayFast84
08-10-2012, 10:57 AM
When You turn the key does it even prime?

deadtrend1
08-10-2012, 11:31 AM
unless it a car that you're eh about.....cut out an access panel in the back hatch area.....easy peasy

I am probably most against this being that its not that difficult to do correctly from the bottom. The rear end doesnt even need to come all the way out (just pivot on the front of the lcas), and LS1 tanks are even easier due to the rubber filler tube.

BonzoHansen
08-10-2012, 11:33 AM
LTb1ow and the others are right, there are a few things to review first. got a fuel pressure gauge?

I am probably most against this being that its not that difficult to do correctly from the bottom. The rear end doesnt even need to come all the way out (just pivot on the front of the lcas), and LS1 tanks are even easier due to the rubber filler tube.

why do that when you can play fuel line roulette! lol

sweetbmxrider
08-10-2012, 11:34 AM
I am probably most against this being that its not that difficult to do correctly from the bottom. The rear end doesnt even need to come all the way out (just pivot on the front of the lcas), and LS1 tanks are even easier due to the rubber filler tube.

Agreed. I've had my tank down more times than I care to admit and I wouldn't hesitate to do it again. Its really simple, just takes time.

MyFirstZ
08-10-2012, 12:37 PM
I have no desire to take my tank down and have become accustomed to access panels here at BMW and probably will use on of thier doors to seal it properly

Jersey Mike
08-10-2012, 12:54 PM
I have no desire to take my tank down and have become accustomed to access panels here at BMW and probably will use on of thier doors to seal it properly

Care to post a picture?

If it's an OEM piece, I'm sure it seals well and keeps the fumes out.
But from DIY jobs I've seen in Fbody write-ups, it's just a small piece of sheetmetal, a hinge, some small bolts, and maybe some caulking. Hence my curiosity about this OEM option.

chrisfrom nj
08-10-2012, 01:40 PM
check the fuel pump relay first

WSex
08-10-2012, 02:10 PM
unhook the filter and see if it works
if not go to relay box pull the relay swap it or hotwire it
pin 30 to 85(someone back me up on that one)
see if youre even getting power at the hot pin which is 30.

TaKid455
08-10-2012, 02:24 PM
Should have stated that its a car I am looking to purchase thus I do not have it in front of me. I have not seen that car in person as of yet. This is the reason for the discounted price. just looking to see if it could be anything major aside from relay/ fuel/ pump issue. Hope it wasnt a flooded car. Supposed it would have other issues if that was the case.

WSex
08-10-2012, 02:28 PM
wheres the car located? if youd like some help

did he say it runs when he pours fuel into the intake because that just sounds bad to begin with and big chance it was hydrolocked my opinion

TaKid455
08-10-2012, 03:27 PM
In a carb or up right style intake I would say this would be OK. in an longitudinal (LT1/ LS) style intake, pouring fuel into it seems a touch difficult, unless sprayed into the MAF. Car is in PA.

WSex
08-10-2012, 03:35 PM
yeah i know but you said poured and ls1
im near westchester everyday if its not too far i can check it out
i got some jumpwires and my meter
i can also check if its pa turnpike eastwards or rt 1

MyFirstZ
08-10-2012, 06:24 PM
If it is cheap enough and you have the know do it. Brake clean, starter fluid can all be sprayed in the intake to get it running. If...... You can get hold of an injector cleaner that is used by pressure into the fuel rail and you get it running I would buy it do a pump and filter. Wish I can lend the ones we have at work but they are shop yools.

sweetbmxrider
08-10-2012, 09:55 PM
You jump 30 and 87 to bypass a relay but I would just see if power is getting to 87 first after you verify the relay operates. Worst comes to worst, punch and kick the bottom of the tank while someone cycles the key with a few seconds delay, might get it going again.

TaKid455
08-14-2012, 03:33 PM
Thanks for the input. wound up passing on the care. at 14k, it seemed like a lot for anon running car. even if it was a 30th T/A.

The concerns escalated as I would not be able to test other systems w/o the car running. FOr 5k, I would have snagged it.

maroman88
08-14-2012, 11:10 PM
14k for a non running 30th anni?