I put in a stereo system over the holiday, consisting of an amp, cap & sub to mate with my existing stuff. I hooked up the amp and sub, started the car and tested it out. It sounded grea. Yee-haa.

I added the cap to the setup and reconnected the negative bat terminal (actually made 2 or 3 seperate connections before finally getting the wire screwed in correctly) and blew something. The stereo works fine, all the lights and whatnot come on, the fuel pump primes and the starter turns the engine over but I can't get it to actually ignite. I can smell a bit of fuel too.

I checked all the fuses, even replaced the 2 12v30a silver ones in the f.block. My guess is a fusable link. The one by the battery seems ok. Where's the one I'd be looking for? How would I test it when I find it?

Help, this really pisses me off after a weekend of getting everything right only to be shot down while hooking my battery back up.

Thanks,
Eric

 

I'm trying to trace down these links but my Chilton manual is speaking to me in another language. It says there are 4 on my 89 Firebird. I found the one at the battery, that was easy. Some folks on here say there's one at the steering column and the book says there are a couple "in the circuit at the bulkhead connector and stops at the junction block". I'm not seeing those either.

 

Chase down where the power is missing.

Are you getting 12volt to the distributor with engine in 'run'? 12volt to the ECM? Those are the two most likely causes for it to turn over but not start. Most of the other fusible links provide power to accessories like the fan, etc.

My first thought would be pass key decoder.

 

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if your gettin fuel, you most likely arent getting spark, so check ALL fuses in every circuit that is involved with the ignition system, also check you electronic spark control module inside the disributer if all of your fuses are good

 

naf- I'm very green with auto electronics, how would I check for 12v at the distrib? I get 10.69v at the ECM fuse (which is not blown). I bet the low voltage is due to the car being cranked and not started since Saturday.

NINA- I don't know for sure that it is a link, it was my best guess (and I hope it is a wrong guess) I don't know either if I'm getting 12v to the coil. How do I check that?

--> I do have a DVO meter, just not totally sure of the procedures on how to utilize it

sail- I'm pretty sure I've got fuel and no spark, I have pulled each fuse in the block and checked it, I just need some direction on how to check for what I've blown or done

Thanks for the replies, I'll be checking back often.

EDIT: along NINA's line of thinking, when I hoooked up the negative cable to the battery, I never heard any pop or sizzle (other than the little bit AT the battery terminal) or saw/smelled any smoke. Maybe this indicates that it wasn't a link?

 

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It may seem like I know enough, but really I'm simultaneously searching TGO and looking thru the instruction manual for my multimeter (is that a DVO?) trying to figure out what to do.

I pulled the black & gray connectors on the coil: I put the red lead on the red wire prong and the black lead on the gray wire prong of both the black & gray connectors (individually of course). The result with the key in RUN was .5 (MM set at 20v DC) on both.

So....I'm not getting enough fire to the coil or distrib, right?

 

When you are using your Digital Volt Ohm Meter (DOV), you would select 20V DC, place the black lead on a known good ground (like the neg terminal on the battery or a grounding bolt on the block/head) and place the red lead on the wire you wish to see voltage on.

Make sense?

You checked all of the fuses under the dash and under the hood? How about the relays?

 

I'm not an audiophile so I apologize for the stupid question, but where did you install the capacitor? Do these things install in series with the amp power wire or?

Since something went wrong right after you installed the capacitor, I'd look there first.

 

Yes, that makes sense. I hooked up the red lead to the gray connector/red wire and the black lead to a ground screw from the negative battery terminal for one and then tried it again with the black lead hooked to the negative battery cable itself. Both read the identical .5v of the previous test. Am I still doing something wrong?

I have DOUBLE checked the fuses under the dash and they are fine. I (again) know nothing of relays and which ones to check.

 

Paulo, I'm not an audiophile either. I like fast and loud music, and with no mufflers I need loud. Your questions isn't stupid, I just learned about this stuff last week.

The capacitor installs between the battery and the amp. I'm less sure it is the capacitor itself as the entire audio system works great; the REST of the car sans ignition works fine too. I kinda chickenshyted the negative battery cable when I was putting it on for the first time, making 3 or 4 "touch it and back away" connections before getting it screwed into the negative terminal. (I read of DIRE consequences if the cap is hooked up wrong). My guess is something about that (as the cap charges itself with 12v in about 5 seconds) may have shorted or blown something.

Honestly I wasn't really dying for a new system, but it's something that seemed like a good challenge to take on. As with most projects associated with this car, I always get at least one other course in how-to when I take on any new project. Needless to say, I'm cursing myself for this one.

 

If you have the black lead on a known ground, and the red lead at the connector at the distributor WITH the key in the "run" position and your are only getting .5volts, then you have a problem.

If 12V is not getting to the hot side of the distributor, then there is a problem further up in the system.

Is your check engine light coming on when you turn the key on? If it is not, then the computer is not getting power.

You checked the ones under the dash, that's good. But what about the ones under the hood?

Paulo57509 has a good point too, when in doubt, put everything back the way you had it.

 

The very first thing I did was disconnect the audio system from power, it's not at this party. All of the dash lights come on, even the idiot light. As I said the fuses under the dash are fine and the one at the battery for the ECM is fine. If there are more, where are they?

 

You could jumper 12 volts to the distributor from teh battery and try to start the car that way. That would prove whether or not you are getting a good 12v sent to the distributor or not.

 

Am I going to incinerate myself doing this? (haha)

So, how would I go about doing that? I've never jumpered anything.....

 

I'm going to try my hand at the wiring diagram in the sticky (from AutoZone) for my car. It began life as a 305 TPI...

My logic is this, please correct me. I've established that I'm not getting sufficient voltage at the pink wire/gray connector at the ignition coil. Using the "engine wiring" diagram, that places me at the ignition switch. If I follow that onto the next page ("body wiring"), that shows the coil wires I'm looking at going into a fusable link. Where is this link? Am I on the right track?

 

A fusible link provides 12volt to the ignition switch, but your switch is passing 12volt to the starter solenoid, so this link should be good.

In hooking up your audio equipment did you fiddle with anything under the steering column? The actual switch is down there actuated by a cam/rod from the key.

When checking for power at the ignition coil, you removed the two wire connector that DOES NOT go to the distributor and checked for 12 volt on the (should be) pink wire with the ignition switch in 'RUN'? Probe the connector inside with one lead while the other is on the negative terminal?

 

Hi naf, I did not mess with the steering column at all. Yes, I removed BOTH plastic connectors on the coil and checked them BOTH individually (just to be sure). I clipped the pos lead to the red (or pink) prong and the neg lead to the battery negative and then to a ground bolt currently in use (2 tries, same reading). The voltage reading bewilders me but......

I figured I'd melted something somewhere but I'm just not sure where, until I found this. The pics below are of a melty connector right around the coil. It comes out of a loom with a bunch of other wires the coil may be using. Looking at it (the pics are kinda bad) there is evidence of melting on the wires going into both sides of this connector as well as a bunch of melted plastic inside. One of the leads on the short side of the connector is obviously burnt and both leads on this connector are gummed up pretty well.

The $64,000 dollar question, what is this connection for and might this be my problem? Also, why would this have happened?

 

Looks like something's been added? Is that a spark controller mounted to the firewall?

 

I do run an MSD, what's in the picture is the tach adapter mounted to the heater box.

The burnt part is a GM piece, any ideas? I'd really like to know what it's function is before I go off cuttn' and splice'n......

 

I think the crispy plastic part may not be my issue. I tried the voltage test again and got about the same result as before. SO by disconnecting this damaged part, I am guessing it's not in the same circuit as the coil. Back to square one and it leaves me with another question, what's so insignificant on my car that I've run this long with it like it is?

Where else can I look?

 

I measured 11.64v going into my MSD box (midway up the red wire from battery) and got the same measly .5Xv at both gray & black coil connector pink/red wires and at the splice for that same pink wire coming from the MSD.

I'm thinking I've cooked my MSD, would you all agree?

 

Sounds like it. If you have a good 12v going to the MSD box and nothing coming out, then it is fried. Did you not have a fuse for the power wire feeding the MSD box?

 

No fuse. It didn't come with a fuse holder so I figured it didn't need one. That and I didn't wire it up to begin with. Do you recommend I install an in-line fuse? If so, what rating would be best.

Along that line, I still cannot figure out why this happened. As I said earlier, I made a few connections with the negative terminal and the negative cable trying to get the screw into the terminal threads, why did this cook my MSD? Was it that my cap was an "instant on" type thing where it's drawing a good current immediately upon the connection being made?

 

Anything after market that needs power, needs a fuse. Especially if it is runnign straight to the battery.
You will need to look at the specs of the MSD box to find out how much amps it is drawing to decide what size fuse you need.

 

Talking to MSD is a good idea, so I called them. I told them what I found out and they said my tests didn't matter, I needed to do the tests on their website to determine if the box had died. Ok, tests done and it's dead.

They told me that since the box was wired to the negative battery cable itself, I may have spiked the voltage when I was trying to get the cable to screw in and to insted ground the MSD to a chasis ground, this will prevent the same problem from happening again (they say). I asked about the fuse and they said it's not necessary as the MSD has internal somethigorother that can protect it from these things (guess my box was made after they started putting this stuff in).

I sent the MSD out to be fixed. If they call me back and tell me the box works I'm going to jump out of a window.

 

You ran the neg wire from the MSD box straight to the neg terminal? I personally would rather ground it to the frame or chasis.

I am sure that MSD says that they have some sort of internal fuse but it doesn't hurt to put an inline one in yourself to save you the trouble in the future.

Hopefully they can fix your box and get you up and running soon.

 

Thanks for your input, Uncle Paul. In the interest of saving face, I did not wire my MSD, that was done by a "pro".