1990 RS 305 TBI

I've had this problem for a while with my car and I want to put an end to it.

My car doesn't want to start sometimes, it won't crank at all, I'll key the ignition and nothing happens, no cranking, then I will get out of the car and move the negative wire on the battery around a bit and it will start cranking. I believe it could be a faulty negative wire or something like that, because sometimes what happens is I will be jumping the car and it will get one big crank and then it just stops, no more cranking, not even the death rattle click of a dead battery. This proves to be almost no helpful evidence at all though, because one could say that it is something in the wiring that loses it's connection because the motor moves when it starts cranking, so naturally one would think that because the motor is moving, the connection gets severed, and it doesn't crank anymore. But then there are other times that when it will crank, it does so flawlessly, just keeps cranking, especially when the battery is dead and it's being jumped, I'll crank it for like ten or more seconds and it will finally catch, but it doesn't falter.

I really need to solve this, any help is gratefully accepted.

 

Clean your battery and check the ohms with a meter on your battery cables. That's the best place to start. Make sure you tighten the cables to the battery so they do not move. The negative cable needs to be tight to the block.

 

Well the problem with keeping them tight is that when I mess with the negative cable to try to get it so that it cranks, different positions of the cable cuts power completely from the car, so I kind of have to find an area where it will conduct the power.

 

replace the neg batt cable make sure that you have one going from the batt to the frame and one from the frame to the motor +clean the batt terminals.
and while you are replacing the cable make sure that you have a clean connection on the frame and motor. this means sand the connecting areas clean of any paint and use a star washer in between the cable and the frame and motor
this will give the best connection at those points

 

Is the other ground wire that comes off the negative cable and attaches to the frame supposed to be really little? It's really small, like 12 gauge or smaller. Also, I checked the connection of the negative cable to the block and it's snug on there, no play what so ever. I also unplugged it from the side post and looked in the hole that it screws into and it looks really clean, no corrosion at all. The smalller ground wire that goes to the frame is also on tight, no play there either, what else could this be? Could the cable just be to old?

Is it safe enough to say that this is what's causing the power not to get to the starter? Is there any way to tell for sure?

 

Best thing to do is to definately replace the Negative battery cable. Cables do go bad after time. If you are able to move it on the battery, then you do not have it tight enough. Also, get your battery tested. Cables are cheap and testing the battery if free. To make sure the cable is bad, check for power at the starter with a volt meter. Then test the negative cable with an ohm meter. Either way, you should make sure your connections are tight and you should not be able to move anything easily.

 

there is power at the starter, I checked it previously, if there's power at the starter could it still possibly be the negative cable?

 

use a volt meter put your negative lead on your terminal run your positive lead on the case of your starter have a buddy crank it and watch your meter and perform a basic voltage drop test. you wanna see a reading in millivolts but nothing above 1/4 1/2 a volt. if you get somthing bigger you probibly have corrosion in your wire under the insulation or breakage but this should isolate it to the negative side.