A quick rundown on my setup. 1998 LS1/T56 installed in a 1990 RX-7. Rear monuted battery. Battery is good, cables do not have corosion... I have since looked at my cables for bare or pinched spots. None.




So last weekend I was driving my car home from an auto x and after shifting into 5th the whole car lost power. I had pushed in the clutch and was still rolling at around 50 mph and tried to start the engine back up... wouldn't crank. Not even the sound a dead battery makes when you try to crank it. Just nothing. I rolled the car to a stop wondering what on earth was going on. Checked all of my connections from the battery all the way till where it ties in with the cars main fues box. All were tight. Tried to start it again... This time it turned over about a quarter turn then gave me the click click click like the battery was dead. I sat on the roadside for about 10 minutes then tried it again. It started this time, but a little slower than normal. Then when it got started up it idled up to about 3,000 rpm and pulsated slightly. It would stay reved up but the idle would smooth out if the IACV was disconnected. I figured ok this sucks but I need to get it home. Drove it home and parked it.

I had been thinking maybe my battery had a broken plate in it or something and was just dying on me.

Fast forward to tonight. Checked everything over again... made sure all the connections were good. Everything was fine. I put the battery from my Civic into the RX-7 to try the bad battery theory. Hooked up the battery and got in the car. Lights work, turn the key to on... fuel pump turns on as normal. Everything seems fine. Turn the key to start... starter turned maybe half a turn then I heard THUNK and the car went dead. I turn the key off and all the power is gone... then I hear another THUNK from the back of the car. Get back there and some smoke had come out of the battery and the battery cables were warm to the touch. I quickly disconnected the battery and went to the front to check under the hood. The two ground wires from the engine to the body were HOT! Hot to the point that I touched one and had to yank my hand back off it to stop from being burnt.


**This makes me think there is a short where power is being dumped into the engine block and then run back to the battery through the engine ground wires**


Well, I tried to put the battery back in the Civic and it seems the RX-7 totally killed it. It is flat out dead. Wont even turn on the dome light. I am in disbelief as this was a nearly new, fully charged battery. It wont even turn on the dome light now and will not take a charge.





What the HELL gives here?!?!



I have had people tell me it could be a bad alt. or bad starter. What do you guys think???


Help a guy out that is missing the fun of driving his car.

 

Definitely a short to ground somewhere. Maybe not a direct short (the kind that causes sparks) but a higher resistance short. If you don't have a multimeter go buy one. It seems weird that there are no blown fuses though. It's probably coming from something that handles a lot of current. If the ground wires were hot and there weren't any smoking wires anywhere else then the juice is coming from a pretty big wire. Just for ***** and grins see if your battery cable is hitting your engine block anywhere. Also, maybe something internal to the starter that's F-ed up (no fuses to help you out there) or your wire to the starter is grounded out against the block. Good luck with this one, I'm curious to find out what the culprit is.

 

I just noticed you are parting out a car. How much for the shocks that hold the hatch up? Mine don't work anymore.

 

i gave my cables a good close look over. couldnt find any areas where they were pinched or rubbed through or anything like that.


also checked around with a multi meter. the power cable coming from the battery to the starter is not shorting, neither is the cable that goes to and from the alt.






is it possible that the starter or alt could have an internal, somewhat intermittant short?



i am trying to be careful here as i dont want to fry any more batteries, or even worse, start my car on fire.

 

not sure if i have those... i will take a look.

 

Disconnect the battery and then use the ohmmeter to try and find the short. That way you save whats left of it. Ground one of the leads and then touch the positive side of some of those wires with the other lead. You should show an open circuit. If you are showing low resistance then that is your "problem wire". If you need help with the ohmmeter let me know. Lots of people are familiar with voltmeters but the ohmmeter gets confusing to folks at times. I'm no expert, but I've done a lot of elecrtical troubleshooting on aircraft. Good luck.

 

i have tried that, can't seem to find much.

 

I'm out of ideas if none of the wires are shorted to ground. I still think it has to be related to the starter or power cable.

 

yeah... i am kind of leaning towards the starter. but can that be checked? i am really nervous about messing with it too much. i already feel lucky that i didnt start the car on fire when the battery popped.

 

Well, everything can be checked its just a matter of how much work it is to do it. Check the resistance throught the solenoid, not sure how much it should be but 0 would be a bad #. You can check the resistance through the starter itself if you have a way to close the solenoid that won't actuate the starter. But since you always have the short, that would have made it show up only when you tried to start the car. Or you can just measure the resistance from the positive side of the starter (where the power wire hooks up) to ground. It should be open, if any kind of low # shows up thats bad. Just be sure you have the battery disconect when you are using the ohm meter or you take a chance on messing it up (the meter).

 

well after taking a while break with working on the car to wrap up with finals and projects i dug back in and yanked the engine tonight.... turns out a damn bolt happened to land on the starter and bridge the gap between the battery lug and the starter body!!!








it doesnt look like it came from my engine or any other spot on my front end... no bolts were missing. what are the damn odds!!

 

DAMN!, you got lucky. The bolt looks like it started to weld itself to your starter. Like you said, what are the odds.

 

That sucks! You didnt pull the motor just to get to the starter did you?
Glad you found the prob

 

nah i am doing a bunch of other stuff as well

 

That's unbelievable. Glad you got it figured out.