1998 S70 GLT no crank/no start issue

[hadaverde]

Hello all, first time poster here so please go easy on me.

My 1998 S70 GLT is experiencing a no crank/no start issue that started out as intermittent, but now I can't get it to start at all. When I turn the key on, dash lights etc. come up just fine, but when I turn the key all the way forward to start, I get an audible single click from the starter but no crank.

Background since the beginning:

Initially I had this problem a handful of times, a little over two years ago, with each instance occurring several weeks apart, always after driving the car somewhere and parking it for a relatively short period of time (under two hours, for example going to the grocery store, shopping, then returning to the vehicle to head home), then trying to start it again. After a few attempts at starting, or letting it simply sit for 10-15 minutes, it would then fire up just fine. On one of these occasions, I did some web searches on my phone and found the troubleshooting tip of running the shift paddle through the gears then trying it again, on the chance it was an issue with the PNP switch. This did seem to work that one time, but when I attempted the same "fix" on subsequent occasions, it did not resolve the issue.

After that point I was doing some other work on the vehicle, as a coolant hose had begun leaking, so in addition to replacing hoses I also replaced the starter. This seemed to resolve the problem for a time, so I assumed the original starter had been going bad. However, after maybe 6 months had passed, it started happening again. It was again very intermittent, and most often occurred after the vehicle had been driven and then parked for only an hour or two before needing to be started again, but very occasionally it would also happen on initial startup after being parked overnight or for a full work shift. Sometimes it would resolve simply by turning the key back off then immediately trying again, other times it would need to sit for 10 to 20 minutes and I would have to make multiple attempts at starting it before it would actually turn over.

The issue started occurring more and more frequently, and taking more repeated attempts over a longer period of time in order to resolve.

It seemed that the issue would occur more frequently and take longer to resolve when temperatures were higher - either during hotter weather where the outdoor temp was higher, or trying to restart the vehicle within an hour or so of having completed a longer drive (driving 30+ minutes at a stretch).

Recently I have had a separate issue with the vehicle's original alternator going out, and have actually replaced the alternator three times in the past two months because I had one remanufactured out of box failure and another remanufactured one that failed after about a month of use - both of which were the auto parts store house brand - and finally put in an AC Delco which I believe resolved the alternator problem. Leading up to and throughout this time frame though, the no-crank issue has increased in frequency even more, until a couple weeks ago, the day after I replaced the alternator the last time, the car would no longer start at all no matter what I did. To clarify, the car DID start after the alternator replacement, about 3-4 times, before it would no longer start at all.

I have verified that the battery is fully charged, and the battery itself is only about a month and a half old at this point, having been replaced during the alternator replacement debacle. I have read about an issue like this being caused by the security system relay in the 210/211 position in the relay panel under the dash, however my vehicle does not have any relays in those positions, so I assume this means that this vehicle does not have that security system, and therefore the issue cannot be caused by this. I have replaced the starter relay in the the engine compartment relay panel, and then today replaced the starter again. upgrading from the auto parts store's house brand to a Bosch, because I thought it might be the starter itself going bad...but I am still getting the exact same symptom - no crank, with a single click occurring at the starter itself.

My brother is a more experienced home mechanic than I and has helped me out with all the parts replacements and troubleshooting that I have done so far, but he and I are both stumped. Any ideas as to what we are missing?

[scot850]

Have you changed the electrical portion of the ignition switch?

I think a 95-97 850 or 98 V/S/C70 will work if you try pulling one from a junkyard. Worth a shot and if it works it may be worth having a new one available in case the used one goes too.

Have you checked the battery for parasitic drain? Favorites include the glove box light staying on with cover closed.

Neil.

[hadaverde]

I have not tried swapping out the electrical portion of the ignition switch yet, however I did get one and have it on hand. I guess that is going to be my next attempt at fixing it. I don't think there is any parasitic drain going on...the battery has been charged with a charger between attempts to start and various troubleshooting steps, and it hasn't seemed to make any difference.

[454cid]

I wonder if your replacement starter is already going bad. Is that also a part store item, like the troublesome alternator?

I think the key switch that was suggested is also a good thing to explore..... I've wondered if mine is slowly going out on my car as it doesn't quite feel right and acts like it may be worn/dirty sometimes.

[abscate]

If you are getting the click at the starter , your ignition switch is sending the signal down to the starter on the green wire. It’s worth checking thst connector for corrosion.

You need to check voltage from battery to starter at the red cable. I bet you have loss there and so your new battery and new starter can’t have a cranking party.

Test voltage at battery, then carefully move the red probe down to the starter lug and look at voltage there. It should be the same +-0.1 Volt

[foggydogg]

I know you've already touched the wires going to the starter multiple times now, but I had the identical problem on mine some time ago, and what solved my problem was ever so slightly crimping the female spade connector on the signal wire to the solenoid; It always seemed firm enough to the touch when I fiddled with it, but may have been just tenuous enough that the added resistance of a loose connection made the system unhappy.

[hadaverde]

Update: Problem persists though the ignition switch has now been replaced as well. I have yet to try tightening down the spade connector or doing any voltage testing - I've been working six days a week, and usually nine+ hours a day recently so I don't have a whole lot of time or energy to troubleshoot during the week. Once I dig back in to reach the starter again, I'll try those and see what happens.

Thanks to everyone for your suggestions!