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Discussion Starter · #1 ·
Have had my 2000 Grand Prix GT w/144k miles on jack strands for almost 2 years now. Was doing a bunch of suspension and brakes then took a stab at redoing my A/C system (compressor blew) but gave up for now and did compressor delete pulley.

The engine started and ran as recent as a year ago. But now after I've got everything back together the car cranks but no start and no fuel pressure at the Schrader valve is the obvious issue right now.

Fuel pump fuse is good and tried jumper-ing the FP relay pins but no fuel. Did the security re-learn-reset procedure and still no fuel.

Anyone have anymore common troubleshooting tips for this problem?

Thanks in advance
 

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Well, the first thing I would suggest is to see/hear if the fuel pump is running when the key is first turned on. You can use a listening device on the gas tank which should make it easy to hear the pump running.....if it actually is running. If not, in a pinch I have used a hammer to tap on the fuel tank body to jar loose a stuck pump motor. Sounds a bit off the wall, but in a pinch, this works. If you can't get the pump to start running and the wiring at the fuel pump is good, you may need to replace the pump assembly. Best of luck... Mr goodwrench

PS, when the ignition is first turned on, the pump only runs for a few seconds and then stops. AND, does the gas tank actually have fuel in it?
 

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Discussion Starter · #3 ·
Well, the first thing I would suggest is to see/hear if the fuel pump is running when the key is first turned on. You can use a listening device on the gas tank which should make it easy to hear the pump running.....if it actually is running. If not, in a pinch I have used a hammer to tap on the fuel tank body to jar loose a stuck pump motor. Sounds a bit off the wall, but in a pinch, this works. If you can't get the pump to start running and the wiring at the fuel pump is good, you may need to replace the pump assembly. Best of luck... Mr goodwrench

PS, when the ignition is first turned on, the pump only runs for a few seconds and then stops. AND, does the gas tank actually have fuel in it?
Thanks Mr. G--- yes we have a full tank of gas. Today I will have a helper to switch IGN on-off so I can listen for fuel pump activity and relay clicking. Also, can you tell me exactly where to 'hammer' (or tap?) on fuel tank? On the top the fuel pump-cover area, behind the back seat maybe?

Thanks again~!
 

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Thanks Mr. G--- yes we have a full tank of gas. Today I will have a helper to switch IGN on-off so I can listen for fuel pump activity and relay clicking. Also, can you tell me exactly where to 'hammer' (or tap?) on fuel tank? On the top the fuel pump-cover area, behind the back seat maybe?

Thanks again~!
When you hammer on the tank, hit it on the bottom side of the tank moderatly hard......don't wack it so hard that it might bend/dent the bottom of the gas tank. I suppose one could use a board on the bottom of the tank so you don't bend/damage the tank itself. Maybe recheck all the wiring and make sure the ground wire for the pump motor has a good ground connection. You may need to look at a wiring diagram for this to confirm wire colors and ground wire color. Also, using a test light and a schematic diagram you should be able to see if there's actually power getting to the pump assembly. Double check the pump ground wire for a good clean connection to ground. Hope some of this helps. At the miles you have on the car, the pump may be worn out. That would require a new pump assembly. Jake
 

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One last thing, using a "test light", confirm there is actually 12 volts going to the pump assembly and again, confirm the GROUND wire has a clean secure connection. Jake (mr goodwrench).
 

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Discussion Starter · #8 ·
Do other accessories turn on when you turn the key to accessory position?
Yes, everything runs including CD-player, etc., my problem has been, working by myself, I couldn't 'hear' anything but the IGN-DOOR chimes! Today I have a helper and, after some manipulations--- the car finally starting pumping gas! Whoohoo!
 

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Discussion Starter · #9 ·
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When you hammer on the tank, hit it on the bottom side of the tank moderatly hard......don't wack it so hard that it might bend/dent the bottom of the gas tank. I suppose one could use a board on the bottom of the tank so you don't bend/damage the tank itself. Maybe recheck all the wiring and make sure the ground wire for the pump motor has a good ground connection. You may need to look at a wiring diagram for this to confirm wire colors and ground wire color. Also, using a test light and a schematic diagram you should be able to see if there's actually power getting to the pump assembly. Double check the pump ground wire for a good clean connection to ground. Hope some of this helps. At the miles you have on the car, the pump may be worn out. That would require a new pump assembly. Jake
How's this for 'off-the-wall' recommendations--- took off inspection cover behind the back seat rest to access top of fuel pump assembly, lines and wiring. Gently tapped on the top of that nest while helper turned key... we finally heard fuel pump whirring for the standard couple of seconds, then shut off.

Went to the fuse/relay box and confirmed the FP relay was clicking as helper turned key on/off. We did this several times to be sure of what we were hearing and then tried the starter---Voilà!--- she fired off! Rough, but eventually smoothed out. We're putting all its previously drained trans/coolant fluids back into the car as we speak.

Did more research earlier this morning and I learned that this key-on/key-off sequence is factory repair manual recommendation whenever fuel system pressure has been bled off for any reason. It also states that this key-on/key-off sequence may need to be done several times to build enough fuel pressure for starting. (and that is just 1 little bitty psi---#@&!??)

That all makes sense now because over the past two days, we had previously done the key-on/key-off thing a DOZEN OR MORE TIMES already!

In conclusion, thank you everyone for your helpful suggestions--- this makes for a great forum. And I hope this info may be helpful to others in the same boat because thankfully. we missed the bullet on fuel pump replacement... for now.

ciao~!
 

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From the way you described this scenario, the fuel lines probably had air in them and it took a while to get that out before enough fuel could get to the injectors. Mr goodwrench
 

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Another thing I've done in days gone by is to pull the schrader valve out so getting the fuel to the fuel rail is easier and quicker and also gets the AIR out of the fuel line. Best of luck from here on.... Mr goodwrench
 

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Yes, everything runs including CD-player, etc., my problem has been, working by myself, I couldn't 'hear' anything but the IGN-DOOR chimes! Today I have a helper and, after some manipulations--- the car finally starting pumping gas! Whoohoo!
You should hook up a pressure gauge to that shrader valve on the fuel rail and test your pressure. They don't cost that much or you could borrow one from AutoZone.
 

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Discussion Starter · #13 ·
SEE MY PREVIOUS comments. I was the OP of this thread a year ago and I have the same problem again. I suspet the fuel pump may be bad but am stuck at this point: 2000 Grand Prix GT, 144k miles. Everything bone-stock.

SITUATION: Car was starting and running fine on a regular basis for one year. Then car sat idle for a month or more on BATT charger only with no start ups. So now I need to move the car and we have the NO START problem. BATT fully charged and engine turns over fine. Checked for fuel at schrader valve and it is dry.

Assuming we've lost fuel pressure/prime, we did the on/off IGN key sequence at least 100 times, (key on 2 secs then key off 10 secs) Still no fuel at shrader valve.


SPRAYED starting fluid into air inlet and engine runs briefly, then dies, still no fuel at schrader valve.


CHECKED FUEL PUMP FUSE; good.

Tested FP RELAY w/12V BATT power only applied = solid click sound heard/felt = good.
OHMS ZERO when relay switch closed.

CHECKED FUEL PUMP RELAY INSTALLED w/IGN KEY ON. Tested FP RELAY w/key on = solid click sound heard/felt = good.
OHMS ZERO when relay switch closed.


REMOVED FUEL PUMP cover in the trunk, unplugged 3-pin female connector, and with IGN key-on, tested 4.8v to 5v (at all 3 pins?) of the FP female power connector. (weird)

With female power connector at FP, plugged into FP, and with my ear 3 inches away from Fuel Pump, helper did IGN key on/off sequence but no sound from FP at all.


POWER at FP TESTED W/IGN w/key on: While helper cranked engine over, I tested power at FP female power connectors which still only gave me 4.8v to 5V (all 3 pins?). Not sure I am testing voltage correctly here. See photo


JUMPERED FP RELAY AT UNDERHOOD FUSE PANEL: Removed FP RELAY from fuse panel. Jumpered fuel-pump/fuse panel RELAY females 87/30 WITHOUT re-installing the RELAY. Have 12V at fuse panel females 87/30. But only getting 4.8v to 5V at (all 3 pins) on FUEL PUMP female power connector IN TRUNK.

With FP Relay fuse panel jumpered (87/30) Shouldn't I get a full 12v at the FP power connector in trunk? Unless wiring and/or pump are bad? Again, not sure I am testing voltage correctly here.


Again jumpered FP relay females 87/30 AND installed FP relay on top: same 4.5v to 5v at the FP female power connector in trunk. Helper then switched IGN ON while I checked voltage at each female connector = still the same 4.5v to 5v at the FP power connector. Same setup, helper turned engine over multiple times and still got the same 4.5v to 5v at the FP power connector.


What should my voltage read at the fuel pump female power connector pins at start up? When running?


As suggested, I tapped on top of FP several times, turned key on, still no sounds from FP.

Anyone have a method to jumper FP female power connector at the fuel pump, directly to 12V BATT? Like which pins are PWR & GND???

ALSO: anyone have recommendations for bidirectional OBD II scanner w/fuel-pump on/off feature? $500 maybe. $1200- not!

Stumped.
 

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Pump is most likely bad. I had this issue with my GTP after it got older and sat a few times. Once you get to the point where you're having to tap the pump to free corrosion from that motor sitting, it's already on borrowed time. Even an inexpensive pump will make it seem like you just put jet fuel in there.
 

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1998 GTP coupe. All stock and rust free. That will change soon.
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hot wire a harness to the pump out of the car and apply 12V.
I had issues with aftermarket pumps, the pump would run but the check valve would stick closed = no fuel
 
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