V1 LeoZug's Montana Street Goblin - '05 Cobalt SS donor

[Leo Zugner]

Hey all. I got my main wiring harness hooked up but I’m having an issue. Even without the key in, when I connect the battery something is coming on in the engine area. It’s sounds like a fast fan but we are thinking it’s the heat exchanger pump? I’m pretty hard of hearing to it’s hard to know where exactly it’s coming from. Maybe I switched some wires somewhere? I don’t really know where to start.

 

[comegetjoe]

Well you gotta start by figuring out what it is thats coming on. If its a fan, you can feel air. If its an IC pump, you should be able to feel it humming or buzzing.
Did you connect battery power to the IC fan directly?
Is your key in the RUN position when you connect the battery?

 

[Leo Zugner]

Agreed. I’ll have to get someone to help me find what it is. The key isn’t even in the ignition when it comes in. Just connecting both terminals of the battery makes it come on. It’s gotta be connected directly to the battery somehow right?

 

[Desert Sasqwatch]

Pull one fuse at a time - IC pump, fan, fuel pump - if you are having trouble finding what is coming on.

 

[Leo Zugner]

We are wanting to make sure that the two cables going to the starter are correct. If they were backwards could it cause an issue like this? For what it’s worth, when I connected the battery cables and it was making the “fan” sound, I turned the key to ACC to see if the gauges lit up and they didn’t. I don’t remember if they did in the cobalt or not, but that seems like another clue that something isn’t connected correctly.

 

[Leo Zugner]

Pull one fuse at a time - IC pump, fan, fuel pump - if you are having trouble finding what is coming on.

I started doing that on the rear fuse box. I’ll keep you posted.

 

[Leo Zugner]

If it was somehow hard wired to the battery would the fuse not affect it?

 

[Desert Sasqwatch]

That's what you're trying to find out. If you end up pulling all of the obvious fuses, then it becomes more of a possibility.

 

[Leo Zugner]

I tested the obvious ones but still have the issue. Do you think having the starter wires switched could do it?

 

[Desert Sasqwatch]

Is the starter spinning? If no, what makes you think the starter wires are switched? There should be 2 wires, a thick 12V wire and a smaller 12V wire for the solenoid. The ground comes from the mounting of starter to the engine block which is grounded through the frame to the battery.

 

[Leo Zugner]

Haven’t got far enough to try to crank the starter. My dad just had a lingering thought that we may have switched the two wires going to the starter. The battery cable and the one going from the starter to the fuse box.

 

[Rttoys]

I would check all that first before hooking up the battery again. I would think if it was the starter turning, you would definitely know. Have someone under the vehicle while someone else touches the battery connection. Get your hands and ears on everything so you know what’s coming on, then go from there.

 

[ah.b.normal]

Haven’t got far enough to try to crank the starter. My dad just had a lingering thought that we may have switched the two wires going to the starter. The battery cable and the one going from the starter to the fuse box.

In most builds the original battery feed(+) went from the battery in the trunk to the "jump starting post" on the fuse box and then another large(+) wire ran from that fuse box jump post to the large upper starter post. (The feed wire to the alternator(8*?) also runs to that lg post from the back of the Alt but is is much smaller than a battery wire. That feed wire must remain to enable the Alt.)........ In most Goblin builds, during disassembly, you remove the main battery wire from the jump post at the fuse panel. During assembly you can shorten it and connect it directly to the lg post on the starter. But the big(should be) RED wire from the battery can be run from the battery either to the lg top post on the Starter OR to the jump post on the fuse box, either way works. Either way you wire your battery +, that similarly sized battery + wire always runs from that jump post on the fuse block to the starter large upper post on the starter solenoid........... Here is where folks can trip up, The ground from the engine is a lg black insulated wire bolted onto the engine somewhere near the starter, And the(+) battery cable from the fuse block jump start post on many Cobalts were also insulated in black (with just a little red collar at the starter connection which can fall off).............. Leading some builders to accidentally connect that engine ground with the Battery (+) on the starter. Dead ground to the engine and no starter action....................... It didn't help that The cobalt (short length black wire) Engine Ground wire originally was in a section of conduit taped along the Battery + wire that comes from the fuse box jump post!................ Make sure that the engine ground is complete, from somewhere near the bellhousing to the frame.(if that ground is not connected it will cause slow or no starter action.) It originally ran from the engine to a stud under the left headlight, it just needs to go to ground on the frame.............I know! That' a lot of words. I wish I had pix............... It is "simple" but also easy to mix stuff up........ Just remember(on those big wires) RED Always = hot+ EXCEPT when it doesn't! Because sometimes those RED wires are actually BLACK with red markers on the ends that rot and fall off or get greasy and turn black after a decade of use and abuse.(a really awful mistake IMO but I just have to fix them, not re-engineer them.)

 

[Leo Zugner]

I appreciate the input guys. Thank you. I’ll keep you posted.

 

[Leo Zugner]

Got it fixed! Put both wires in the top post of the starter. Now that sound doesn’t happen and I have dash power. So that’s good.
New issue is that I don’t have crank. I’ll look around to make sure I didn’t miss any wires.

 

[Leo Zugner]

I don't have my fuel pump wired up yet because of the mismatched plugs but do you think that could somehow affect whether the car could crank? Its also weird that the starter(?) was making that noise before when the battery was connected, but now with the starter wires seemingly correct, I get nothing. Any ideas of a good place to start?

 

[Rauq]

The only way I could see your starter doing anything and it not being obvious that it was the starter is if the solenoid is not pushing the pinion out to engage with the flywheel. I guess if you put hot to the starter solenoid post the solenoid would kick the pinion into the flywheel, but I don't know if that'd make a continuous noise (although I'd imagine it would be unhealthy for the solenoid). Other than the starter, the intercooler pump and the fuel pump are the only other things I can think of that would be making any sort of electrical noise in the back of the car. Then again, I have my A2W intercooler and fan in the back too, so if yours is back there, check that, but also I'd think you'd have some air movement to help identify that.

I wouldn't think that swapping any of the wires on the two posts of the starter would cause any issues you're describing. As others have laid out, the hot post on the starter is supposed to be where the battery, alternator, and power supply to the fuse box all come together. I think the solenoid post on the starter is just a solenoid that grounds to the starter body/engine block so putting power to there not through the crank relay would cause the solenoid to kick the pinion into the flywheel but not do anything else.

I can crank my '06 LSJ without the fuel pump connector connected to anything. I'd guess an '05 is the same and I don't see anything in schematics that would indicate otherwise.

I'd start with identifying for sure what's making your noise. Is your A2W heat exchanger in the front with a fan? I used the fog light power wire that DF ran to the front and back of the chassis harness to power my A2W fan. That means when I hit the ACC switch on the DFKC-supplied switch panel, the fan turns on. I did have a small missed solder on one of those switches, not related to the HX fan in my build, but I could see a different missed solder there turning the fans on with the key switched on.

But for sure identify what's making your noise first. Then we can go into if the PCM is satisfied with things to give you a crank. If your instrument cluster isn't lighting up, decent chance it's not satisfied.

 

[Leo Zugner]

The only way I could see your starter doing anything and it not being obvious that it was the starter is if the solenoid is not pushing the pinion out to engage with the flywheel. I guess if you put hot to the starter solenoid post the solenoid would kick the pinion into the flywheel, but I don't know if that'd make a continuous noise (although I'd imagine it would be unhealthy for the solenoid). Other than the starter, the intercooler pump and the fuel pump are the only other things I can think of that would be making any sort of electrical noise in the back of the car. Then again, I have my A2W intercooler and fan in the back too, so if yours is back there, check that, but also I'd think you'd have some air movement to help identify that.

I wouldn't think that swapping any of the wires on the two posts of the starter would cause any issues you're describing. As others have laid out, the hot post on the starter is supposed to be where the battery, alternator, and power supply to the fuse box all come together. I think the solenoid post on the starter is just a solenoid that grounds to the starter body/engine block so putting power to there not through the crank relay would cause the solenoid to kick the pinion into the flywheel but not do anything else.

I can crank my '06 LSJ without the fuel pump connector connected to anything. I'd guess an '05 is the same and I don't see anything in schematics that would indicate otherwise.

I'd start with identifying for sure what's making your noise. Is your A2W heat exchanger in the front with a fan? I used the fog light power wire that DF ran to the front and back of the chassis harness to power my A2W fan. That means when I hit the ACC switch on the DFKC-supplied switch panel, the fan turns on. I did have a small missed solder on one of those switches, not related to the HX fan in my build, but I could see a different missed solder there turning the fans on with the key switched on.

But for sure identify what's making your noise first. Then we can go into if the PCM is satisfied with things to give you a crank. If your instrument cluster isn't lighting up, decent chance it's not satisfied.

Thanks for the feedback!

I should have written that we thought it might be a pump making noise, not the starter. I miswrote that.

Since I put the battery wire and the wire from the starter to the fuse box on the top post of the starter, the sound stopped happening when I hook up the battery. Now when I turn the key to ACC, the dash gauges light up and the fan on the heat exchanger at the front turn on, which I think is a good thing? The problem now, is that when I turn the key all the way I get no crank. I'll need a second person's help to check for sure, but I also don't hear the starter solenoid click. I want to offer ideas but I just know so little about how this part of a car works...

 

[Gtstorey]

Unfortunately, there are about a billion ways to get a no crank on m modern car, so it's going to be hard for us to figure out what you have wrong. All we can really do is through out completely random "no crank" solutions. In general, though you have to pick on end of the electrical "chain" and work your way along the diagrams until you find the break in the chain. But teaching basic electrical shooting via forum is next to impossible.

 

[Leo Zugner]

Unfortunately, there are about a billion ways to get a no crank on m modern car, so it's going to be hard for us to figure out what you have wrong. All we can really do is through out completely random "no crank" solutions. In general, though you have to pick on end of the electrical "chain" and work your way along the diagrams until you find the break in the chain. But teaching basic electrical shooting via forum is next to impossible.

I hear ya. The electrical stuff is the worst part. I've been dreading this stage. The last car I scratch built, took 9 months to figure out the electronics.