1990 240sx starter keeps running

[BlackScorpion]

Hi there,I have a 1990 240sx Automatic with fairly high mileage.Only had it for a couple of months, and it's been running great. Completely stock, not modified in any way - lady driven most of it's life. Never any clicking or any weird starter problems since I've had it.

This morning, went to start it and the starter got stuck spinning away. It wouldn't turn over the actual motor of the car, just the starter was spinning. I guess the starter motor was spinning, but its solenoid didn't actually engage the starter gear to the flywheel?

In any case, I couldn't get the car to start. I pulled the key out and the starter was STILL spinning!!! I was stunned! Tried starting it again, and no difference - starter just kept spinning away.

Anyways, I eventually disconnected the battery, reconnected it, and everything was fine again. I was able to put the key in and start it like always.

I'm trying to think of the logic behind the starter:1. the ignition key is turned activates some sort of relay.2. the relay energizes the starter.3. when the starter gets energized, it both spins and pops out to engage the flywheel at the same time.4. when you release the ignition key, the starter relay stops energizing the starter.

For the symptom to happen, I think there must be more than one failure - the relay would have to get stuck AND the starter must be partially failing as well.

Or does the starter have two separate positive inputs - one for the spinning, and one that moves the gear out?

I haven't found any threads that describe my problem exactly, so I thought I'd try a new one.

Thanks!

[ufakefe]

I ran into the same exact problem except it was not a nissan it was a john deere.but thats besides the point as all starting systems are similar or the same.Im not saying that this is your problem and this is how to fix it. this is what I had to do inorder to fix my problem. lets start off that your right on track, your right about not only 1 thing is bad. what I had to do is change the starter relay because it was stuck. im sure you know how a relay works? i dont mind explaining if you dont. lmk. anyway I had to also change the starter. because only sometimes the solenoid would pop out the bendex. I hope I helped some and didnt get you confused. I kept it short and simple. also I can teach you how to check a relay with a 9 volt battery and a meter. its very simple.

[ufakefe]

and for your question about how a starter works. there is constant battery volts. and at the coil theres a pin the only gets volts from the ign on crank. that is fed from the starter relay. hence the starter spining with the key off.

[Rucca]

Key on (energize relay which energizes starter) - starter gets power which energizes a solenoid that pushes the starter gear out, when it gets out far enough it physically completes a circuit to an electromagnet that holds it in place and the circuit also starts spinning the gear which starts your car. You let off on the key and the relay stops energizing the starter which breaks the magnetic field and the starter gear (no longer held in place by the electromagnet) returns to the its original position.

So that is another vote for replace starter and starter relay, although I suppose you could just try the relay first. I imagine, if the relay is sticking, we can kind of fathom that maybe it is all crusty and causing lots of resistance in the circuit which would not give enough energy to allow the starter to operate properly. Just a wild idea, you probably need both items.

[POS_S13]

the drive gear isn't making contact with the flywheel teeth. the current may be fine, but physically the starter is failing, change your starter.

[BlackScorpion]

Thanks everyone for your replies.

I happened again recently, only this time disconnecting/reconnecting the battery didn't help. The ignition key was out, the starter was still spinning without actually cranking over the motor.

We had to actually tap the starter a couple of times with a hammer to get it to disengage. Definitely a starter issue.

So I have no problem locating the Starter to replace it. However, I'm not sure where the starter RELAY is located?

It's a 1990 240sx automatic.

Thank you.

[Rucca]

The ignition key was out, the starter was still spinning without actually cranking over the motor.

We had to actually tap the starter a couple of times with a hammer to get it to disengage. Definitely a starter issue.

Leave your battery unhooked at all times - if your starter is getting a signal to start, or is shorting out internally and running, you are at a high risk of your car catching fire. If the starter runs on it's own for extended time, it can overheat and cause a fire. I would also recommend leaving your parking brake on at all times, you have an auto so the problem isn't likely, but with a manual trans left in gear, this problem can cause the car to move itself.

The starter relay is in the front right of the engine compartment, not with the other relays though, it is own it's own. You'll likely find it next to the battery or somewhere near the battery. I believe it is blue.