I have a fuel pump kill switch hooked up in my car (along with other theft deterants). I notice at times, during spirited drives, the switch gets LITERALLY HOT!

So hot its not able to hold at times.

What could cause this?

TIA --migs

 

Heh, welcome to Highschool Physics Take the following example: If you're trying to power some huge space heater, and have it plugged in to one of those $2 white Wal-Mart extension cords, it's going to get hot as ****. If you upgrade the extension cord to a higher gauge, it won't get hot. I'm willing to bed you're using a switch that isn't meant to handle anywhere near what you're putting through it. Go hit up Radioshack for a higher gauge switch

 

You could also consider using a relay with the switch, so that the full amperage isn't flowing through the switch itself, but rather through the more robust relay circuit.

 

and some higher gauge wire too

 

My VAFC gets like that too.

Hey migs!

 

Use a relay...

 

Don't touch your switch..

 

 

yeah...i gotta say, thinner wire = less resistance.

 

Dont touch the switch!! How am I going to de-activate it!?

 

lol!

 

you meant thinner wire = more resistance, right?

 

Yes. I'm sure he realizes that now.

 

That is an excelent idea. Put a 30 amp relay on the pump circuit and make sure that you use a large enough wire gauge. The problem you describe is obviously related to using too thin a guage and not only is this dangerous but it is also choking off current to the pump itself which could degrade the performance of the pump and potentially cause a lean condition if the pressure drops too much.

P.S. A better kill switch idea IMHO is to disable the main PGMFI relay. Its the gray box with the 8 wire plug bellow and to the left of the dash fuse box. The white wire is the one to disable.

Mike

 

 

Use NAWWSS; it'll go that switch down.

 

Well, after months and months running the kill switch and getting hot. It finally failed on me this morning. I was driving 45-50mph down a road. My motor surges. It felt like I sucked in water. I thought I blew it but no way I could have because it was sunny as could be.

My car stalls but still rolls, I coast to the center lane. I had to rip off the switch and twist the wire together to make it start backup.

 

ghetooo....That sucks migs I hope that it doesn't happen to me.

 

well you said" some higher gauge wire", higher gauge, as in a higher number= thinner wire=more resistance....your mistake

 

For these that suggest using a relay, wouldn't it mess up the electical current that would cause fuel pump to malfunction?

 

no

 

Well, people have said to use a thicker (lower number gauge) to reduce the heat. I think the problem is in my switch.

The wire is cool, its only the switch. Ill be getting a new switch

 

I've never had a problem with a $3 20a Autozone switch in any of my personal cars... running Walbro pumps...

 

I would carry a fire extinguisher with you until you fix this. Hot electric switches=fire.