94 Mazda B3000 problems

[swezy207]

Hey guys, I posted in a ranger/mazda forum and nobody could help with this. I know theres a wide variety of people on here, some mechanics that could maybe help.

My truck, 94 Mazda B3000 4x4 has a problem starting sometimes. It has a mind of its own. sometimes it starts right up, other times it wont. I drive it for a little bit, shut it off, go back 10 min. later and it wont start. I can always tell when its not going to start because when I turn the key forward I can or cant hear the fuel pump kick on. so I know it is and electrical problem somewhere that has to do with the fuel pump. always happens at the worst time too. sometimes kicking the gas tank seems to help.

kicking the gas tank helps sometimes so it must be the fuel pump right? you would think anyway, I replaced the fuel pump and it still does it. I also replaced the fuel pump relay. usually it is only when I go to start the truck, but just recently it has died WHILE driving it.

Im thinking about wiring the fuel pump to a toggle switch inside the cab, will this eliminate the problem? how would I go about doing this? I want to make sure it is safe, and no chance of sparking anywhere near the fuel tank.

thanks for any help any one may be able to give!

[4VRYNG]

I have a 2004 B2300 that I have a somewhat similar problem with and found the solution with mine. Mine has a safety switch down in the passenger side under the dash. I think it shuts off the fuel system in the case of an accident. My buddy is really tall and kicked the wires that plug into it. The safety switch itself didn't get tripped but the harness got kicked loose enough that it wouldn't start.

Another time it would start but not idle. I pushed on the plug again and it cured it.

Not sure if the 94 had the same kind of switch but that sounds a little like the problem I had.

Mine is just above below the top of the floor mat under the dash on the passenger side.

Good luck.

[4VRYNG]

So, with our friend GOOGLE I have discovered your truck has this switch in the same location. It's called an "Inertia Switch". I'd look into that.

here is an adobe PDF of the wiring diagram.

Page 10

http://www.google.com/url?sa=t&rct=j...6iHMpB36Y-JU8Q

[swezy207]

ok thanks...

I found the inertia switch, so next time it hapens I will pop the little red button up, shake it around, then push it back down and see if it starts. Ill keep you posted, thanks for the help.

[4VRYNG]

Mine was never the switch itself just the wiring harness connector to the bottom of the switch. Hope that solves it.

[microgoat]

Sometimes the wiring harness going to the tank will corrode. That's a tough one to spot, you have to ohm out the wires and see if they have extra resistance.

[swezy207]

I think I figured out the problem... its actually a relay under the hood, but not the fuel pump relay, I always thought it was the fuel pump relay. I put a new relay in and it has started every time now.

But... not I broke my front passenger side axle shaft, or u joint or something, it rattles like crazy. Hopefully I can just get a new vehicle soon, I got a new job that I start on the 13th and my pay will go up significantly, so that should help.

thanks for your input guys!