something shorted- car wont start - where do i start looking?

mostsmooth

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Hi all,
95 gt
car was driving, but not well, some pops and backfires. I drove the car yesterday and it was fine, no problems.
opened the hood, checked timing, it was a little erratic. turned it off and tried to start it again and there was a bit of smoke near the battery area. I was in the car, nephew was at the engine and saw the smoke, so I can't explain if it was a ton or not, but he said it wasn't much. the timing light was connected when this was all happening.
the car didn't start, didn't even crank after the smoke.
Looking around, we found that a spark plug wire was laying on the header and was melted a bit, and there were marks on the header that could be the results of arcing (not sure). the plug wire did come off of the plug. probably why the pops and backfires were happening. I didn't think to check those first because I had recently checked they were all connected.

now when I try to start the car, it doesn't crank at all. just a click sometimes, and sometimes nothing happens as if there wasn't even a battery connected.
sometimes the dash lights come on normally, sometimes they don't.
when the key is in the power position, there is a clicking noise in the back near the fuel cutoff switch. I disconnected the cutoff switch and the clicking noise was still there.
the underhood light was very dim (like, very very dim, barely lit) and was pulsing in sync with the clicking noise.

I checked all the fuses in the box near the battery. they were all good. I pulled the 3 relays in that same box and looked at them, nothing looked burnt (i don't know what else I can do to test them). there must be more fuses somewhere, I will check them once I figure out where they are (and if they exist), but because the dash lights come on sometimes and sometimes they don't, it seems like not a fuse issue?

Car has an MSD ignition box, I disconnected and bypassed that and it didn't change anything.

so, my guess is that whatever the voltage is that is in the plug wires jumped to the header and damaged something electrical. my question is, is there a best place to start looking, or do I just have to check everything?

the battery is disconnected now.

Thanks for any suggestions
 
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mostsmooth

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Start with checking battery voltage, have it load tested, next check the battery cables, do a voltage drop test on them.
Thanks,
Battery is brand new, after the smoke. the old battery was old and while it would start the car, if I had to crank the car a bit to get it started, there was a chance it would run out of juice, even after recent charging and driving and such. it was time for a new one, so this triggered me to buy a new one.

the battery cables, you think something went wrong and now they need to be checked, or you think they should be checked regardless?

thanks again
 

General karthief

wonder how much it would cost to ship you a pair
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mostsmooth

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bit of an update:
things seems to be worse than originally. not the dashlights do not come on at all when i turn the key. inititally when the trouble started, they would sometimes come on, sometimes not, but more often not. they would only come on infrequently.

i checked all the fuses (1 box in engine compartment and 1 box under driver side dash). i found a burnt fuse and got excited, thinking my problems were solved, but no, it seems it was the fuse for the air bags.

i want to try this step 3 from the checklist, even though i think the problem is elsewhere:
3.) Jump the big terminals on the starter solenoid next to the battery with a screwdriver - watch out for the sparks! If the engine cranks, the starter and power wiring is good. The starter relay is also known as a starter solenoid.

Use a screwdriver to jump the big terminals? so i should pull the relay slightly out of its spot and get a screwdriver in between some terminals?(which ones???) or are they say i take the relay out all the way and stick a screwdriver in soemwhere? (again, where???) the relay has 4 prongs, so 4 slots, not sure how i could stick a screwdriver into two slots at once, so im guessing i will be jumping a couple of the prongs with the screwdriver.


here's a question:
i cant remember, but if you turn the key to the accessories position withouth pushing in the cluth, you should get power to accessories, dashboard should light up, etc? that seems to make sense, but i cant recall.

thanks
 

General karthief

wonder how much it would cost to ship you a pair
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Do you have a dvom (digital volt olm meter)
If yes, do a voltage drop test starting at the battery
If no, ask Santa to bring you one.
You likely have a bad connection or a bad battery.
 

mostsmooth

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Do you have a dvom (digital volt olm meter)
If yes, do a voltage drop test starting at the battery
If no, ask Santa to bring you one.
You likely have a bad connection or a bad battery.
hi,
thanks for the quick reply
brand new battery.
i have a voltmeter. ohm, continuity, ec. its cheap, but seems to work fine. i used it to check all fuses and grounds.

i will have to look into how to do a voltage drop test i suppose unless it is easily explained.

one other thing, there is some type of fuse (i think its a fuse) located near the battery. it isnt wired to the batter directly, and it is in some 3-inch or so tube-like housing. one side has a pink/white wire, the other side has a black wire. i am going to try to figure out what that is, because there was a bit of smoke near my battery (the old battery, not the new one) and im wondering if that is a fuse that maybe burnt up.

thanks
 

mostsmooth

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finding voltages like 2-5 volts at various parts of the engine. seems bad.

i noticed if i played with the ground from the battery, the underhood light would turn on and off. going to get some replacement wires i suppose.

also, i tried to jumper the starter relay, starter didnt make any noise at all. voltage is getting to the fuse/relay box though. i didnt probe relay slots, i will do that for fun before i go get wires.
 

mostsmooth

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finding voltages like 2-5 volts at various parts of the engine. seems bad.

i noticed if i played with the ground from the battery, the underhood light would turn on and off. going to get some replacement wires i suppose.

also, i tried to jumper the starter relay, starter didnt make any noise at all. voltage is getting to the fuse/relay box though. i didnt probe relay slots, i will do that for fun before i go get wires.
well, i may have gotten ahead of myself. i went back and checked if there was power to the relay, and there was, and while i was at it, i checked various spots around the engine and was getting 12 volts once i scraped off and dirt or rust or whatever coating was on the surface. wire is still not in good shape, so i will replace it anyway.

the negative wire from the battery connects to the block near the water pump/oil filter vicinity. i hear there is a ground wire someplace at the back of the engine maybe? is this a guarantee on 95 gt? any ideas where it is? back center/left/right/top/bottom? where on the engine does it connect?

thanks
 

mostsmooth

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new update:
i bought a new battery cable.
i happen to be somebody who likes to fix things though (sometimes aka cheap), so i cut off the end of the negative battery cable and the ground wire, cleaned up the connector, stripped the cables about an inch, put the clamp back on and the car fired right up. brilliant.
i may or may not just replace the battery cables altogether anyway, but for now it seems problem is solved.
gonna take it for a spin now.

thanks all for any help you provided
 

General karthief

wonder how much it would cost to ship you a pair
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If the wire you worked on is not discolored like green or black then you are likely good.
There are a few ground wires in the engine compartment that are important, the battery ground of course then there is supposed to be a wire from the back of the head on the drivers side to a screw on the firewall near by. There should be a small black wire from the negative battery cable to a screw on the inside fender apron between the battery and the solenoid and there is another wire from there down to a cylindrical connector that goes into that mess of wires called a harness, these are important computer grounds. Another important ground is an orange wire that is in the injector harness and bolts to the intake or back of the head on the passenger side.
 

mostsmooth

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Thanks
It wasn't green or black, just a bit rusty and a little damaged (or a lot damaged apparently).after I cut it,it looked good.
I am aware of the smaller wire from the negative terminal to ground. Mine goes to the metal above the radiator. I tightened that up with a fresh bolt the other day. There is another wire connected there, likely the one you are talking about.

When I put the heads on a couple /few years ago, whatever it was, I dont remember connecting a ground wire, I also don't remember taking one off the heads. I will take a look tomorrow. If there was one there, it could have gotten taken off a long time ago by the people that did the work.

Gonna look for that orange wire as well.
Thanks again
 
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mostsmooth

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Another important ground is an orange wire that is in the injector harness and bolts to the intake or back of the head on the passenger side.
i found what appears to be a red wired (maybe red/white) that has a fitting that is connected to a threaded bolt sticking up out of the lower intake. i think this is what youre talking about? it is connected at the front right of the lower intake with a black rubber boot, kinda like a spark plug boot. i saw a similar bolt sticking up at the back left of the lower intake as well, but there is no wire on it.

i couldnt find any wire on the head to the firewall. will look harder next time i suppose.
 

mostsmooth

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