[OregonSaab900s]

Hi again,

I’m having a weird issue that I’m having trouble diagnosing. This is on an NA 1989 900. Before anything, yes the ecu has been replaced.
Ok, the car started and ran about 6 months ago. Now with a full battery charge and jumper cables on it, no crank just one single click when I turn the key. So I thought it was the starter. Took it out and bench tested it. although it was very worn out it still extended and spun as it should. I then tested a spare starter I had and it worked much better so I thought the old one was just tired. So I put my spare in and I still get the single click from the starter. At this point I thought the engine was seized so I put the car in gear and pushed it. Engine rotated fine. I then got a tow by my dad on a chain and popped the clutch and it ran and drove fine. We then took a screw driver to the starter and jumped the connection and the starter did indeed extend and turn the engine over slightly, but it was somewhat finicky and we couldn’t get the solenoid to fully engage the flywheel but the motor would spin up. I was thinking that maybe there was a bad ground to the engine and I just looked at the negative cable going to the front of the trans and it looks very clean. I did not take it out because it is raining but I plan on cleaning that connection. Is there anything I’m missing? Could it be a relay? I’m not aware of the symptoms of a bad relay and if there’s a suggested test I’d love to hear about it!

thanks!

 

[Mimmi]

Have you double checked ignition switch?

 

[OregonSaab900s]

Have you double checked ignition switch?

Just the connections on the switch itself? Or the mechanism itself? I haven’t dug into the one on this car but maybe I’ll look into that now that you mention it

 

[Mimmi]

Switch itself.

 

[OregonSaab900s]

Switch itself.

Ugh not the easy fix I was hoping for, but I do have a spare. Not looking forward to swapping that part, either the whole housing, or maybe the switch itself if that can be removed. Well, if it turns out to be bad. Thanks I’ll test the switch tomorrow

 

[Cornbinder89]

The fact that it doesn't crank well when jumped at the starter, I would focus on the cables. Good clean connections between the starter and the positive post, and good clean connections between the neg post, the car chassie and the engine. Both the chassie and engine need a good connection to the negative of the battery..

 

[Cornbinder89]

Best, simple test I can give to someone who isn't really up on electrics. Take a remote starter switch (available at any auto parts store) and connect one end to the post on the starter the battery cable is on. the other to the terminal the small wire is on the solenoid
Place a volt meter one the battery cable at the starter and the engine. Press the remote starter button, the engine should crank and the volts should dip below 10-11 volt.
If it does, your cables or connections are bad.
I have an 80 year old truck, all original, 6 volt with a generator, Last week it started just fine when it was 3 deg F out. No jumper cables, nothing but turning the key on and pressing the starter button. It takes good connections and cables to crank, A bad connection will act just like you car is.
Most times it is a simple connection issue, don't go chasing your tail or replacing parts until you have fully ruled out connection issues.

 

[jvanabra]

That's excellent advice IMO. Severely voltage drop can also be a battery capacity issue. You can have batteries that show a healthy 12v at rest but drop to very low voltages under load.

 

[jotzgr]

I concur also. Battery cables in particular can appear undamaged or new on the outside, but can be completely corroded and comprised inside of the sheathing, restricting the flow of current. I have had many batteries also over the years that would show and retain full charge, but had lost their cranking amp capacity and could not put out enough power to turn an engine over. I had a parasitic battery drain on one of my C900s that I finally figured out, and this was the exact same symptom I would get when the battery had been drained. I would have full lights and power, but one click when I tried to start the car, then nothing again.

 

[OregonSaab900s]

Well here’s an update, battery reads 13v and dips to 12v when starting. Yes I think I over charged it a few weeks ago when I was trying to figure this out the first time. But I swapped the battery to my other 900 and it instantly started. So battery is ok. As for the ground connections, I took them off and cleaned them. They were very clean already but I gave them a quick scuff just in case. Still no crank. I don’t have a second pair of hands to test what cornbinder said at the moment, but that will be next.
Also, as I already have started to dig into this… is there a suggested way to test if the ignition switch works properly? If it were faulty wouldn’t I not even get a click from the starter at all?

 

[Cornbinder89]

Get a 2nd set of hand if you need to. testing other stuff because you don't have the hands to check what isn't working doesn't make much sense.
Until you know that the proper voltage and current can make it to the starter motor, everything else is moot.
Until you KNOW the starter and its supply are good, you are more likely to introduce problems than solve them.
Until you have proven that it will crank fine by bypassing everything else, you are wasting your time looking at other areas.

 

[jvanabra]

You can use the TSI socket to test around the ignition switch, which will tell you with a high degree of certainty if the switch is the problem or not.

 

[Cornbinder89]

What jvanbra said, I keep forgetting about that socket. It will not help if the wiring to the starter is the problem. will bypass a bunch of the "control wiring"

 

[jvanabra]

Yep, but tells you which side of the equation the problem is on, which saves a lot of wrenching.

 

[OregonSaab900s]

Well car starts as it should now. It is very weird and maybe someone can explain, but as I read about the TSI socket, I read a result to the test very similar to mine. Seen here:

900S starter not spinning

Like the title says the starter is not spinning. I have not started it for a little over a year. I put in a new battery and when I turn the key I get no response from the solenoid or the starter. Not even a click. I hear the fuel pump going briefly, the lights, windows, etc. all work. While...

www.saabcentral.com

The OP jumpered From the TSI socket pin 1 and pin3 (pin out according to jvanbra diagram from another TSI socket thread, many thanks to you jvanbra) after the pins were jumped their car started and apparently the ignition switch operated normally after that. I tried to see if the OP made any more posts on the issue but as of 2019 there has been nothing new. So maybe it has worked ever since.

now how this is similar to mine…
I had my dad hold the volt meter on the starter and the engine and turned the key… starter clicked once and voltage dropped from 13v to 12v. So that’s the same as at the battery. Then we did the TSI socket test. Pin 1 to pin 3, and got only a single click from the starter while the key was in the position just before start (on position). Confused, we tried the screwdriver again. Screwdriver from positive battery cable post on starter to solenoid switched power terminal, starter engaged engine and moved it slightly until the connection was broken when we backed off the screw driver from the terminal. this may not be the issue but my dad was thinking the starter was misaligned or stuck because of what happens soon. this same screwdriver test had the same result as my first post on this thread, Slight crank only. After this I tried the TSI socket jump again and voila, the car started. Then I turned off the key, and voila again, the car started from the key. (Tried this on and off multiple times and it started perfect each time)

It is confusing that the first time we spun the engine a bit with the screw driver it didn’t start, and now tonight when we spun the engine with the screw driver, then tried to crank with the TSI socket, the car starts fine. I suppose this could be a sign of an intermittent ignition switch, though it is a weird coincidence between my results and ccasteel.

 

[Cornbinder89]

. Screwdriver from positive battery cable post on starter to engine block, starter engaged engine and moved it slightly until the connection was broken when we backed off the screw driver

What you said there should be a dead short. So I have no idea what you are doing, either your terms are wrong, or you don't have a grounded engine block.

 

[OregonSaab900s]

What you said there should be a dead short. So I have no idea what you are doing, either your terms are wrong, or you don't have a grounded engine block.

Yes sorry I meant to the switched power post

 

[jvanabra]

I think you're just lucky, and likely have a bad starter.

 

[Mimmi]

Bad starter which has 1 or more bad field coils, bad brushes or bad armature.
Replace starter motor ASAP.

 

[Cornbinder89]

two bad starters? he already change the original to his "spare" starter. At this point I think he needs someone wo understands the system to be helping in person.
DC motors with bad fields, bad armatures etc don't work "fine" some of the time and not others.
A bad solenoid is a possibility, but having two starters with the exact same fault is unlikely. It isn't impossible, which is why I think someone who knows what they are working with needs to look things over.
It is very hard to diagnose electrical over the internet, esp when the person at the problem isn't well versed on the system.
Before we send a person changing parts on what one "thinks" the problem is, we need to test and prove it. Otherwise you end up chasing your tail.
A armature with a shorted coil or bad bars, high mica etc, doesn't work fine one time and not another. Field coils don't short then un short, same for opens.
The way the solenoid works, it has to get the pinion into the ring gear before it will make electrical contact to the motor. It is possible that the contact in the solenoid is defective and it is possible that both his starters are defective in this manor, but not likely, and less so when it worked fine on a "bench test".
It is possible that the mounting plate on the back of the block is broken or bent, and there are many more "possibilities"
Before I would say change the starter yet again, I would want to be sure of the cause.