The other day my alternator failed. Ok, so I got a new alternator, put that in and now that works. Much to my dismay however the car still wont start when jumped. The starter motor is churning and the engine is turning albeit slowly. I pulled a plug from each rotor looking for spark (I was an idiot and pulled the trailing plugs ) Rotor 1 (the front) trailing plug had zero spark and the Rotor 2 plug had a very weak spark. Both plugs were wet with gasoline when I looked at them. Also useful info is the plugs are basically new and the plug wires are relatively new.

Any advice is really appreciated!

Yours truly,

B_w_S

 

Did you recharge the battery? What is the voltage across the terminals. Normal is about 12.5v.

Reman alternators can also be junk right out of the box. I'll typically only trust OEM or NAPA brand. You can have most parts stores test the alternator to see what kind of voltage it's outputting. You want to see about 13.5-14v.

 

No, I don't have a battery charger. (Or anywhere to hook one up for that matter. Apartment Complex) I was trying to jump the car from my friend's Infiniti. The alternator is Duralast brand and I'm pretty sure it's good. Either way though my understanding is a dead alt shouldn't affect starting the car?

Forgot to say.... 1985 1st gen GSL

 

I would pull the battery, personally, find a charger and charge it. You can get a charger for $40.

Maybe take the alternator in and have it tested like RotoryRocket suggested.

Good luck

 

Thanks guys. I went through the motions and the alternator was fine but the battery was fried. I ended up having to get a new one and it started fine.

So embarrassed right about now. . . . That was a beginner mistake.

Thanks for your time!

 

check the starter selenoid

 

This is a pretty general problem, pretty much starter or faulty battery.