truck won't start

[atc82]

ok here is the deal--couple of nights ago i accidentally left the interior light on and ran the battery down. tried to jump it off, but it wouldn't start. i screwed my fuel pressure gauge in to the fuel rail and i was getting no pressure at the rail. so i then tried to start the truck with a new battery to see if it made a difference. i let it run for about a minute and it seemed to run kind of rough. i killed it and started it again to see if my problem was solved. so far so good. i am thinking that maybe the old battery didn't have enought juice to power the fuel pump. i kill it a second time and now i can't get it to start. i turn the key to listen for the two second fuel pump buzz but i don't hear it. I plugged the fuel pressure gauge back into the rail and i am not getting any fuel pressure with the ignition on. i think my pump must have taken a crap on me but i am not sure. any ideas?

ps. i just replaced the stock pump this summer with a the kit from racetronix which included the hotwire harness and the walbro.

 

[Lynn D. Brown]

Start/Fuel Pump problems

Start/Fuel Pump problems

Aaron,

I assume a fuse came w your wiring kit ? U may want to check that.
The newer Hi-Vol pumping systems pull alot more amps. I had to increase the fuse size on my GN double pumper from 15 to 20, and
then to 25 Amps.

The hot wiring kit has a good purpose - ATR measured the voltage
drop in the stock 16 guage wire all the way back to the Fuel Pump,
and found that there was a 3V drop. In other words, U were getting
about 9-10 V at the pump instead of 12-13 volts - a drop of 25 % !

 

[Blake]

Check your fuse to see if you popped your fuse. Truck will crank all day but won't start if the ecm B fuse is blown.
Also make sure the fuel pump relays are good. Swap known good relays. I don't have one but I believe that Racetronix uses the stock fuel pump relay to "turn on" the Racetronix relay. The A/C relay is interchangeable for the stock fuel pump relay if you want to try that.
If not, here's something else to think of. If you try to start a truck with a dead battery it is a strain on the alternator. Did you happen to see what the meter in the dash looked like when you started it up? If your voltage was in the toilet or you tried to start it over and over and over with a dead battery you may have burned up the rectifier bridge in the alternator. AKA alternator death. AutoZone will test them for free
Let us know if we can help.
Look for bad connections too. Just because all of the extra work that was done.
Blake

 

[atc82]

i upgraded the ecm-b fuse from a 10 to 15 as instructed by people from the board when i changed the pump. i checked both of the ecm fuses and they are both good. i may call racetronix and see if they have any ideas. thanks.

 

[SY756]

I would first make sure your getting power all the way back to the pump with a voltmeter. Trace down the power wire to the pump as far as you can and test it. Hopefully something happened to the relay or wires.
I can't figure out how the dead battery would have caused the pump to go out. I have a theory on this but want to check some stuff out before posting and sounding like a idiot .

 

[SY2932]

Might be worth while to check the ground wire that attaches under your bed by the fuel filler neck... There are two grounds on the bed, the other is for the rear lights. When I pulled my bed to install my Walbro, I used the Dremel with a wire brush to clean the metal to bare metal. Then, a liberal coating of grease was applied to prevent further corrosion. Sounds like you might have a loose ground wire as they can cause ALL kinds of intermittent problems. HTH's

Mike Campbell

 

[InvisiBill]

i upgraded the ecm-b fuse from a 10 to 15 as instructed by people from the board when i changed the pump.

In the stock setup, the fuel pump draws all its power through the ECMB fuse. With the Racetronix kit, the circuit that powered your stock pump is used only to turn on the relay, so the pump can get its juice from the big wire you ran to the alternator. You don't need to replace the ECMB fuse with the Racetronix kit, as it should actually be drawing LESS power now.

As was already said, get a meter and check exactly where you do have power. If the ECMB fuse is blown, there won't be power to turn the relay on. If the Racetronix fuse is blown, the pump won't get any power. If the stock relay is dead, the turn-on circuit won't work either.

 

[atc82]

i got the bed off now. when i turn the ignition on i can hear the racetronix relay clicking on and off. where is the stock relay that I need to check? if i have voltage at the pump and still no fuel pressure at the rail, is the pump dead?

 

[kwick6]

stock fuel pump relay is under the hood, it will have a wire hanging from it going to nothing. If you put 12v to that you will be turning on your fuel pump, but in your case a relay.

if you're getting voltage at the racetronix relay, then test it to make sure its letting the voltage pass through it to the pump.

Scott

 

[kwick6]

I guess I could have been more specific.
stock fuel pump relay is located on firewall, near brake booster, closest to driver side. I think there are two relays right next to each other. Find the one with the wire hanging off it.

Also, if you put 12v to that wire, or turn the ignition on, whichever, you can go disconnect the connector for the pump and test for voltage. The connector is attached to the gas tank. Obviously if you have voltage and the pump isn't running than its the pump.


Scott

 

[atc82]

i can't seem to get the connector off the gas tank. i tried pulling it off, but it does not want to come off. it looks like someone before me has tried to pry it off with a screw driver. does it just "lift straight off" or what? it is very brittle looking and i don't want to crack it.

 

[kwick6]

i can't seem to get the connector off the gas tank. i tried pulling it off, but it does not want to come off. it looks like someone before me has tried to pry it off with a screw driver. does it just "lift straight off" or what? it is very brittle looking and i don't want to crack it.

You don't really need to pull the connector off the tank.

It has a clip on it that you pull up on, and the connector will disconnect. I just reach up behind the license plate until I feel the connector, then feel for the clip, pull up on the clip and the connector will come apart.

HTH.

Scott

 

[atc82]

ok, today i got a test light on the connector at the tank. the light lit for two seconds when the ignition was on. so i have voltage at the pump, but the pump doesn't run. I guess i will be taking it out tomorrow to send it off to get another one. has anyone else had a walbro that prematurely quit working? thanks for everyone's help.

 

[V6 Kompressor]

go to a motor shop and ask some of the older guys about what happens to a motor that is fed low voltage... current goes up as voltage goes down so you could have burnt out the windings trying to run a high demand pump like the walboro... the same thing happens to fuel pumps when you don't change out the fuel filter like your suposed to... smoke em if ya got em....
maybe racetronix will go ahead and warranty out the pump... it may have been defective after all... just a short time operating in the extreme zone can kill em.... I have seen running them out of gas kill em also.... make sure that you change out the $4 inlet filter also, sometimes reffered to as the strainer... only or try to get gasoline only from stations that have filters on the gas pumps helps also... Like the Amoco ones or the Exxons are another group that has the outlet filters installed on thier dispensing pumps. Just check around... Small Airport gas is the best, especially the 100 octane type.... but they don't or won't allow it to be pumped in vehicles here, just jugs... and you have to buy 20 gallons worth... Good luck and merry christmas....