car just came back from bret's, who did an engine and LSD rebuild. sometimes the car works fine.

a few nights ago, my dad and i were setting fuel pressure which required the car to be running. so he got in and turned the key to ON (to start the fuel pump), and nothing happened. got out, turned off and on the kill switch, nothing. then we tried again and it worked fine.

now today, we were setting the timing and i was in the car getting ready to start it. turned kill switch on, turned key to ON position (fuel pump started pumping like it should), then when i pulled the choke out, the fuel pump turned off. no power. then tried it again a few seconds later and everything worked fine.

now i realize that if the problem is the kill switch, most if not all of you will not know what to do, but is there anything else to check.... what would possibly cause this?

 

Please? wheres all the electrical gurus?

 

Sometimes old connectors get corroded and become intermittent. Get some Circuit Cooler (I saw it at Home Depot the other day) and shot it at connectors to try to find which changes when the cool is applied. The temp change makes the connector wiggle and hopefully reveal the intermittent.

B

 

Less see... your Kill switch.. it's one that cuts off the fuel pump, or something else?

Try bypassing that for a bit to take it out of the equasion...

It's mainly checking connections, starting from the battery and working your way back.

Wiggle, tighen, and if in doubt, clean and reconnect.

 

I did a long post yesterday but it disappeared??

I would suspect the kill switch first, if no new problem was induced. That switch has been found to be bad on many occasions for several reasons, it may be used infrequently, be mounted in a hostile enviroment, subject to switching small loads but carrying LARGE loads, it's mechanical, subject to much vibration, etc..

Often it can develop a "resistance" through being dirty or pitted and will not reliablaly pass a small current but will (short and) pass a LARGE current. A simular problem can be seen with a bad connection at the battery for example. When you turn on the ignition you have power, but when you switch to "start", the large current will cause a spark at the bad connection and evaoporate the small connection leaving NO connection. In your case the same kind of problem can lead to the problem you describe. The contacts of the switch (or ANY of the connectors) may have a resitance that the small load of just the ignition cannot overcome, but the much greater load of using the starter will bridge the resistance.

For troubleshooting (if you cannot disassemble the switch for inspection or cleaning) you should just use a meter or small test lamp and with the problem present, start at the battery and check for voltage at each spot, battery terminal, battery connection, switch connection, (both sides) and then the rest of the system.

((I noted that you only refered to the "fuel pump" and not the rest of the system. Most of what I said above applies to the WHOLE system not getting power. If the pump is the only thing that does not work the troubleshooting can just be limited to that system.))

Also if you turn the switch on (kill) and do NOT have power to the pump, try hitting the starter without doing anything else first. If the starter engages and you magically have power to the pump as well, this would indicate a poor connection as described above. If the pump fails to begin working but the starter does, you will have limited the problem to just that system. Something else to try, with the kill switch off, press and hold your starter button (or turn key to start and hold) and THEN turn on the kill switch. In this way the kill switch itself will be switching the LARGE load and the "dirt" may be blasted away.

Note that ANY of the connections may develop the problem because they are mechanical. Be prepared to do all of these things if you find yourself coasting to a corner with no power. Also note that the problem can also occur on the GROUND side of things, not just the power side. Since the motor was out, is the ground connection at the engine AND the body in good shape (clean) and tight??

Hope you find the cause before you get to the track!