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2002 Subaru Forester L Electrical Nightmare

Hey guys. So I’ve been working on my girlfriend’s 02 forester with a friend. We just swapped an engine in and for the first night we were finishing up, it ran great. The next day we started on it again and the starter pretty much died. the car has 192k miles on it and had a junkyard starter from before i bought the car so i wasn’t too worried about it. Bought a reman’d starter from Advance (hearing from South Main Auto, those tend to be garbage). We hooked it up and noticed the negative battery terminal getting bright red and start to smoke. We quickly yanked it and noticed the bracket on the starter seemed to be grounding out so we removed it and hooked it back up and the battery seemed good again. Now whenever attempting to fire it up there are electrical gremlins out the wazoo. The doors will start rapidly locking and unlocking, the dash lights go pretty ballistic and then we smell a burning smell. I’m assuming somewhere there’s another short (possibly from the starter again) I’m not really sure where to begin searching for the new problem. I don’t really want to try cranking it to the point where we actually see smoke to trace it and cause more problems.

Disconnect all the starter wires and make sure the ends aren’t touching anything, then verify the battery measures around 12.6 volts. Next turn the key to “on” (not start). It won’t start of course, but are there any weird light flashings, anything else weird happening?

Note that when working with the electrical system good idea to disconnect the battery before removing or installing wires.

With this problem also a good idea to verify the engine turns freely by hand, with a ratchet socket on the crank bolt.

I will check that, however the car did not seem like it was wanting to charge. which of course could indicate the wiring problem spread to the alternator or the alternator itself has failed. We’ve been using a jumper pack to start the car.then removing the jumper.

I think I know what happened with the replacement starter since this same kind of thing happened on a Subaru that I was asked to look at. The starter was replaced on the car and connected up, and then when trying to reconnect the battery connections big sparks flew. I found that the main starter motor power connection to the starter solenoid was shorted to ground. This problem occurred when the starter was installed in the vehicle. The person simply over tightened the stud nut on the solenoid for the main cable connection. On the inside of the solenoid there is a square headed bolt that provides the connection for the main power lead to the starter. When the nut on the outside was tightened up they turned the stud bolt head inside the solenoid and the corner of the head made contact to ground. The result was a dead short to ground. Fortunately they disconnected the battery as soon as they saw the big sparks fly and by just turning the stud bolt slightly counter-clockwise the short was cleared and didn’t damage anything else. In your case I am afraid you may have more of a problem. Since the main ground was glowing red you most likely damaged other ground connections between the engine and the chassis of the car. You are most likely going to have to replace those wires.

Sorry for the late response. so the starter was blown. we got a new new one. we hooked it up outside of the engine and the starter turned. we install it fully into the transmission and it won’t turn over and starts smoking. The only thing I can think of is somethings grounding out when hooking into the transmission. The poisitive cable looks nice and shiny but definitely some scorch marks on the negative cable. we ripped both and unsheathed them. Our next step is going to be replace the cables. I’m wondering how I can check for potential shorts where the starter mounts.

Can the crankshaft be turned by hand with a breaker bar?

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That’s what I was thinking, seized or hydrolocked engine

Sounds like a seized engine. Is there any oil showing on the stick?

Just some food for thought with what I assume is an automatic transmission. The converter will usually come loose with the engine. It MUST be properly inserted before the engine is stabbed an bolted up. There are 3 sets of splines and care must be used to make sure the converter is fully seated on all of them before the engine to transaxle bolts are tightened.

If not, this binds the engine and will lock it up (or as I have seen several times) eventually split the center out of the flex plate.

Yes the engine can turn by hand. we had the engine running with the originlal starter before the elecrical issues started.

I am having a problem getting on to the Car Talk forum so I can only use email right now.

The reason the smoke is happening is because you over tightened the stud bolt nut for positive wire from the battery and shorted the main wire to ground. The bolt head of the stud that the wire connects to is touching case ground inside the solenoid. You just have to turn the bolt back slightly counter-clockwise in order to correct the issue. Checking the resistance between the stud bolt for the main wire and the case of the starter should show infinate ohms when the short is cleared.

When i removed the engine initially we removed the 3 or 4 bolts that connect the engine and torque converter, so when the engine was removed the converter stayed behind. We reinstalled the converter bolts when theengine was reinstalled.

Sorry to clarify only the negative terminal smoked. We actually had a bit of sparking from it originally from being too loose but i don’t think we over tightened the battery. I know we didn’t jam down any of the starter support connections for fear of grounding something. We did see some fraying in the positive cable so we’re going to work on replacing the cruddy wires first then go from there

If the negative wire smoked after the starter was installed in the engine, connected up normally, and the trouble happened when you tried to make the final connection to the battery, the starter solenoid is shorted internally. It is a good thing that the battery connection was loose when the smoking happened, because if the connection was left connected up you would have had a fire. As it is, you just damaged the main battery cables. You should have no sparks happen when reconnecting the battery up to the main supply cables. You can verify you have no short on the cables by checking the resistance between the two leads BEFORE they are connected to the battery terminals.

I think we may have figured it out, we definitely need to replace those cables but We didn’t hook up the ground properly. I forgot there was a separate bracket where the ground goes into the one transmission stud. that wasn’t hooked up so we probably shorted it against itself. we’re going to replace the cables and attachthe bracket but I’m thinking that’s our problem.

The main ground cable for the starter should be located near the starter motor. It allows the high current needed by the starter motor to flow. If just small wire grounds are connected up, the high current will damage them. In order for the cables to get burned that way the starter would have to be running. It sounded to me from your earlier posts that the cables got damaged by just connecting them to the battery. If that is the case then the solenoid is shorted internally.

Problem has been solved. Basically I ding donged and we wired the ground wrong.