Parked the car last night, everything was fine. Came back to it this morning and when I turn the key all I get is a single click. Battery checks out (12.78V). Any other ideas?

 

check all the fuses, if its a manual maybe try and clutch start it. If you can get it started, try pulling the positive terminal, if the car cuts off, its the alternator. but at the same time some cars have separate voltage regulators, really depends on how old your car is. Hope that was a little helpful if at all.

 

Automatic (and no, it's not in gear). It's a 1985, but almost nothing in it is from 1985. Starter isn't all that old. Fuses all look good. The alternator has a piggybacked voltage regulator on the outside of it, but even if that's dead it should still crank with 12.78V at the battery.

When the key first hits the start position the tach jumps, if that tells you anything.

 

In my experience, i'd say starter. I just did this like 2 months ago. I would get the click, and no turnover. The solenoid was good but the crank in the starter wouldn't spin. Also check major grounds. Starter, battery, ECU. It sound's electrical if it won't even crank.

 

+1 sir

 

ECU, lol, ECU. We don't need no stinking ECU (this is 1985...).

Wholesale on a starter is $545...lol.
Though a remanufactured one on the aftermarket is $134. Still, not exactly cheap - any way I can know for sure before I throw a part at it?

I guess that it makes that single click means the wires are all hooked up?

 

Is there someone other than BAP Geon selling parts for european cars locally? Are rebuilds by Quality-Built any good? The closest BAP Geon with a Bosch reman starter for my car is 44 miles away...

Eh, overnight shipping is worth $20.

 

Before you go replacing expensive JDM Merc parts (couldn't resist, sorry..), take some time and see what's happening when you try to start it. Look at the voltage drop between the battery and engine block when you turn the key (you'll need a friend sitting in the car), and you might find something very eye opening.

I've had three different cars with the exact same behavior as you're having, with three different fixes that were all cheap or free. One was a cracked battery clamp with only 10k miles on the car), one was ground corrosion where the ground cable attached to the block, and one was corrosion on the connection to the fuse block. The most expensive fix was a new ground cable. All three problems were found with a multimeter and minimal thinking. In the case of my WRX, I had 5V between the engine block and the battery negative post, and the car only had 20k miles on it. Stupid ground cable is attached under the intercooler, so rainwater corroded the connection, but that's not the point.

My point is that you should always verify that the easy to check things are working properly before worrying about spending a single dime. It may be a starter failure, or something like that, but you could just as easily bolt in a new starter and the problem could still be there. Always know what your baseline is before digging out the credit card.

 

Deal-breaker right there.

In retrospect, the starter has been making a different sound lately. Eh, I'll find out on Tuesday I guess.

It'd be GDM btw.

 

Well, you can sit in the car, but you'll have to trust your friend's troubleshooting ability.