should this be that hot?

[mikekaz1]

By chance I was leaning into the engine bay and touched something VERY hot. Should this connector be this hot? What's the actual name of this piece anyways?

 

 

[Pete M]

that is the fuel pump ballast resistor.  yes it should get warm (it's a resistor), but I admit I don't know exactly how hot.  new ones are cheap enough though.  :thumbsup:

[cruiser54]

Measure the voltage going in with it running and the output voltage at the other end. 

[Megadan]

It's main purpose is to reduce the power to the pump to help extend its life.  Many people simply bypass it by connected the two wires together.

[cruiser54]

It's main purpose is to reduce the power to the pump to help extend its life.  Many people simply bypass it by connected the two wires together.

Actually to reduce the fuel pump noise, not extend it's life. 

[HOrnbrod]

Measure the voltage going in with it running and the output voltage at the other end. 

 

Shound be about 12.5V on one end, 9.5V on the other.

[Megadan]

 

It's main purpose is to reduce the power to the pump to help extend its life.  Many people simply bypass it by connected the two wires together.

Actually to reduce the fuel pump noise, not extend it's life. 

 

That's surprising, because I wouldn't consider the pump very quiet even with that resistor in place.  Usually manufacturers will reduce power (Voltage) to the pump to slow it down when fuel demand is low to prevent excessive fuel heating and extend pump life.  I can see it making the pump quieter since it's not working as hard though, so it makes sense.

[cruiser54]

 

 

It's main purpose is to reduce the power to the pump to help extend its life.  Many people simply bypass it by connected the two wires together.

Actually to reduce the fuel pump noise, not extend it's life. 

 

That's surprising, because I wouldn't consider the pump very quiet even with that resistor in place.  Usually manufacturers will reduce power (Voltage) to the pump to slow it down when fuel demand is low to prevent excessive fuel heating and extend pump life.  I can see it making the pump quieter since it's not working as hard though, so it makes sense.

 

If your pump is noisy with the resistor, it shouldn't be.

 

There was a TSB issued in 1987 that had us guys putting the ballast resistors on the early models built without it, SOLELY to address customer complaints about noise. 

[Megadan]

 

 

 

It's main purpose is to reduce the power to the pump to help extend its life.  Many people simply bypass it by connected the two wires together.

Actually to reduce the fuel pump noise, not extend it's life. 

 

That's surprising, because I wouldn't consider the pump very quiet even with that resistor in place.  Usually manufacturers will reduce power (Voltage) to the pump to slow it down when fuel demand is low to prevent excessive fuel heating and extend pump life.  I can see it making the pump quieter since it's not working as hard though, so it makes sense.

 

If your pump is noisy with the resistor, it shouldn't be.

 

There was a TSB issued in 1987 that had us guys putting the ballast resistors on the early models built without it, SOLELY to address customer complaints about noise. 

 

I have a carter pump, which are normally noisy anyway. It's not obnoxious, but noticeable.  The noise level doesn't change when I bypass the resistor, funnily enough.

[mikekaz1]

Alright! Thanks guys. Knew it was fuel pump related as I unplugged it once and the truck shut down. But didn't know its true function. I guess a dumb by security system would be to leave this unplugged if you don't want any one stealing the truck

[jimoshel]

Or just place a on-off switch under the dash, seat,,,

[daking]

Alright! Thanks guys. Knew it was fuel pump related as I unplugged it once and the truck shut down. But didn't know its true function. I guess a dumb by security system would be to leave this unplugged if you don't want any one stealing the truck

 

 

I removed the resistor, connected the wires to a relay, on the NC (Normally Closed). That is, if the relay is not getting power to the coil, the fuel pump will get power. Basically straight through. I then connected that relay to my auto alarm. This alarm has a Cell phone module, and thus my MJ has a phone number. If my truck is stolen, I can call him up. He will txt me his location. I can txt and have my MJ turn off the fuel pump. If the MJ goes out of a pre selected range (say, 30mi of my home), then my MJ will txt me his location. There are some other security features of this alarm. So, who else s MJ calls home, when he is lost?  :yes:

 

Of course, just adding a simple switch to interrupt the wires that connected to the resistor will be cool too. And it will baffle "would be" thief, as the truck would start and run, then stall-out seconds later as the system switches from full 12v to the resistor.