intermittent no start?

[peytonracer4]

ok so here's the deal. my car randomly does not start. it seems to happen when it's hot but at the same time, it will frequently start fine when it's hot. it seems to be completely random. in fact just the other day it would not start when cold.

the starter solenoid is new (remanufactured). the car will start if i jump the contacts with a screw driver. to me this means the starter is fine.
the electrics work at ALL times. the battery is newish and i have absolutely no reason to believe it's the battery.
in a failed starter situation or not enough power to the starter you will typically hear a click. just one click. my car does not do this.

what does this sound like to you? as far as i know the contacts to the starter are clean. the starter was installed a month or so ago and i cleaned the contacts at that point. the only ones i cleaned were the 3 or 4 touching the starter. nothing else.

thanks for your help.

[jlevie]

Tie a test light to the starter solenoid lead and see if power is applied to the starter when this happens. And check the starter power connection and the engine to chassis ground connection.

[blocke]

Have you replaced the main relay recently?

[peytonracer4]

Have you replaced the main relay recently?

no. which one is that? is it in the fuse box? would i still be able to start it with a screw driver if the relay was jammed?

[jlevie]

The main relay has nothing to do with whether the starter turns over the engine.

[peytonracer4]

i cleaned the contacts on the starter a second time. this time pretty throughly with sandpaper versus a metal file like before.
i've driven it without issues for a few days now. hopefully that fixed my problem. if not i've got an evil wiring gremlin and to be honest, i HATE electrical problems.

[peytonracer4]

well yesterday it did the same stupid thing. except this time when i tried jumping the starter it wasn't getting fuel either. then soon after all the electrics went out.
i saw the negative terminal on the battery sparking so i took the lead off and scratched the crap out of it with a screw driver. this fixed things after a few tries.
it seems like i need to take a day and go over every grounding point on this car and clean them. blah.
i'll update sometime down the road to see if this helped.

[peytonracer4]

so i've cleaned the grounds and am still having this problem. it won't start at random times. more often than not it will not start. it's very annoying.
i can start the car by jumping the starting with a screw driver.

so what's the next step? should i try linking pin 14 with pin 11 to see if it starts? if it does, does that mean the ignition switch is bad? or is there a relay or something i need to check out

[jlevie]

Since the starter will work by jumping power to the solenoid, the problem lies between the starter and the ignition switch.

[Jahman093]

id say ignition ignition switch. they can get old and inside of them they just fall apart and the contacts dont line up

[peytonracer4]

Since the starter will work by jumping power to the solenoid, the problem lies between the starter and the ignition switch.

so my question is: are there any relays or fuses in between the ignition switch and the starter that i don't know about? or should i just replace the ignition switch and hope that works?

[jlevie]

The only thing between the ignition switch and the starter on a manual transmission car is C101. A car with an automatic has the Park/Neutral safety switch in the path.

[peytonracer4]

Am I right in assuming that c101 will never stop the car from starting and that I should replace the ignition switch then?

[jlevie]

Am I right in assuming that c101 will never stop the car from starting and that I should replace the ignition switch then?

That isn't a fair statement. There are other circuits through C101, in addition to the signal to the starter solenoid, that will prevent an engine from starting. But is case it is the solenoid control signal that we are interested in.

Before replacing parts you should properly diagnose the issue. All that takes is a test light applied at at the points where the solenoid signal can be accessed (at the starter, on each side of C101, at the connector under the steering column, and at the ignition switch). It could be that the ignition switch is bad, that one of the connections in the path is bad, that there is wire damage, or even the remnants of a aftermarket alarm system.

[peytonracer4]

Can I use a multimeter instead of a test light?
Am I looking for 12v when the key is in the starting position or when the key is in the on position?
Where exactly am I looking for voltage?
Bottom post on the starter? Pins in the c101? Sorry if my questions are dumb. I just wanna get this solved once and for all