mgracia15

Hey everyone,

So my 2001 Jeep Cherokee (~180,000 miles) won't start.

I just replaced the spark plugs and coil pack so I know that can't be the issue. It has progressed to not starting. For about a week, it has taken my Jeep a little longer to start. The time lapse in which my Jeep started began to increase with each day. Then, one day after work, it didn't start on the first turn. Had to then retry to start my car while pumping the gas and it started. Then it started fairly well the next couple of days (taking a little longer than normal but still starting) but then ultimately wouldn't start last night. It got down to about 30 degrees so I thought the weather was a contributing factor. Tried starting it the next morning when it wasn't as cold and wouldn't start. This time it wouldn't even sound like it was trying to turn on (I think that's called turning over i"m not too sure) but all of the electrical things would be working like the air, radio, dash, etc. So I've done some research and believe I need to either replace the CPS or NSS. I hear that the CPS is the most common cause of this but the symptoms kind of sound like the NSS? I don't know, I need y'alls help.

PatHenry

That behavior sounds like an alternator that isn't maintaining charge on the battery or a battery that isn't holding charge.
You can go to Autozone and they will wheel a test cart thing out to your Jeep, test the battery and alternator without you having to remove them.
They will do this for free.

If you haven't eliminated the simple stuff, you aught to do so before jumping to the conclusion that a sensor is failing.

Maybe I'm missing something, but if you're not getting a crisp, strong "turning over" when you turn the key to "start", it's likely a battery (not uncommon in this weather of late) (a weak "rrr" "rrr" "rrr" sound) or a worn out starter, clicking, no response, or a bad alternator (causing the battery to drain with each start which leads to the weak "rrr" "rrr" "rrr" sound.
​​​​​​​Check them first and go from there.

mgracia15

Thanks, Pat. Since I can't get my Jeep there, I'll try to have someone come out to me. That's exactly what it is. it started as (a strong "rrr" "rrr" "rrr") and transitioned into a weak sound then into nothing when I turn my key other then the dash and radio lighting up as usual.

If it is the alternator, do you happen to know about how much it will cost to get that replaced?

PatHenry

You can take the battery out and take it down to Autozone and they can test it.

An alternator can cost anywhere between $100 and $200+ depending on the quality for the part. If you're having it done it shouldn't take a pro more than an hour (they may charge you for two or have a minimum.. if so find a better shop).. so to have it done would be anywhere from 2-400 roughly.

It's not hard to replace an alternator yourself with a decent set of hand tools, but step back.

First thing is to remove the battery. If you have limited transport, I'd remove the alternator and battery and maybe the starter.
You can take these down to Autozone or Advance or any reputable parts store and they can test each component.
You want to load test the battery and bench test the starter and alternator.
It's important to test at least the the battery and alternator since you want to know exactly what's bad and what's not. A bad alternator can kill a good battery.
If the battery is good you'll want it fully charged when you put the alternator in since the alternator maintains power, it's not good to try to charge a dead battery with the alternator.

Also be aware that usually both alternators and batteries have core charges. If you're unfamiliar it's just a deposit you pay up front and get back when you return the old item.

PatHenry

It might help to get the basic idea of how the stuff works.

The "turning over"/"rrrr" sound is your starter. The starter just kick starts the engine.
In order for the starter to start the engine it requires a lot of energy - a lot more than lights, radio, etc..
During normal operation the starter fires up, drawing power from the battery. Once the engine is started the alternator supplies all the electricity to run everything and brings the battery back to full.
Now if the battery isn't full, the huge draw of power required to start the engine isn't there, so the starter slows down and you get the weak "rrr"

Now there are other causes of insufficient power. A parasitic draw for example - where something is slowly drawing power even when the vehicle is off.
Of course like all batteries, drawing power without recharging will eventually leave you with no power.
Typical lifespan for a battery is 5-8 years. Alternators can last many years or not.. but 180k/17 years would be a very respectable alternator life.

Do you have gauges or lights in your instrument cluster? I'd be curious to know what that looks like for you.

mgracia15

No lights pop up in the instrument cluster when it was driving previous to it not starting and no lights stay on after the initial turn of the key. I've had this Jeep only for about a year and a half now so I'm not sure if the alternator or battery have been replaced since 2001 but I can assume that at least the battery has been changed. I just got the spark plugs and coil pack replaced due to a fluctuation in rpm's; one of the spark plugs was misfiring and burnt out. Could that have residual effects on the vehicle?

PatHenry

I doubt there's anything to worry about with that. If everything's running fine then that's that.
So you have lights and not gauges then? Does the battery light appear when you're starting it? In other words, you should see the battery light light up when you first turn the key to "on".

If nobody has warned you already, the big thing to be careful of with the 01 is to not let it overheat since a well known casting flaw in the 00 and 01 heads can cause a cracked head which is a big problem.

mgracia15

Yes, all of the lights light up right away when i turn the key as per usual. voltage gauge is just above 12V which means that the battery is okay, right? All other electrical things in my Jeep work well. As I turn the key to start the car though, it doesn't do anything. No noise, nothing.

Ah I didn't know that. How do I prevent it from overheating?

RocketMouse

just over 12 for the battery itself it right in the good range. should see 13-14ish when charging.

Just out of curiosity... how old is the actual ignition switch in the Jeep? Is it loose at all when you have the key in? as in, can you move it around at all?
Also... check and recheck your cables to your battery and ground. Maybe it's possible you're getting enough of a connection to activate the accessories, but not enough when it comes time to crank it over.

Another thing you could try, even though your battery is registering in the good range.... try a jump start with cables with a second vehicle and see if there's any difference.
I don't know what it could be to have that much parricidal draw right at starting, but it's worth a shot and wouldn't cost you anything to try it.

RocketMouse

Other than keeping a close eye on it...and proper maintenance, not much else you can do. It was a known flaw in the '00 model year heads. An 0331 casting number I believe. others please correct me if I'm wrong on the number.

PatHenry

^^^^^^^ This. Basically if you see the temp gauge start creeping up (Normal operating temp is about 210) anywhere near the "red zone", immediately pull over and shut off the engine. Don't neglect proper coolant maintenance (checking the level periodically, flushing the system every so often, checking for cracked or stiff hoses.. etc).
That said, on my old 2000 TJ with the 0331 head, I had several mis-adventures with overheating and after 305K miles on the motor the head never failed. So it's not something that if the engine hits 230 degrees it's guaranteed to fail or anything. It's just important to know so if you have ANY signs of cooling problems you understand there's an extra level of priority in resolving them.

PatHenry

You definitely exhibit all the classic signs of alternator failure. Your gauge should read 14 something during normal operation (right about the middle) and at 12 may indicate that the battery is holding the 12v but less than proper power is being put out by the alternator.
Since you have a volt gauge you might not have a battery light... I can't recall.

Report back to us how the testing/resolution goes!

mgracia15

It doesn't have a battery light on. I did try to jump it with another vehicle and there was no change at all. I was able to turn on my headlights just fine, radio, fan, everything else. Does that signify that there is a problem with the alternator or the starter you think?

PatHenry

Could you clarify?
As understand it you had a progressively slowing ability to start the vehicle and it got to the point that it won't start. You get lights.
Now if you try to jump it, it won't crank/turn-over?

If you are sure you had the cables connected it very well could be a bad starter then.
What I would do is try to jump it again. Make sure your cables have a good connection. I usually verify cables are on right by turning the lights on in the dead car and when the lights come on the cables are on with a good conection. You might do a variation of this by looking at your volt gauge and seeing that it's reading 14 when the key is on.
If you know you have a good connection and you still get no cranking, the next step would be to pull the starter and take it to Autozone and have them bench test it.

As I mentioned earlier - If you have limited transportation, but lots of time, I'd pull the battery, alternator and starter and take all 3 to Autozone so it's one trip. If you have limited time but access to another vehicle, you can start with the battery - take it to Autozone. Have it tested - if it's good then have them charge it fully.
If you have a good, fully charged battery, the starter should fire strong and "crisp". If it doesn't, pull the starter, have Autozone test it. If it's bad, replace it (and for giggles have them prove it's working by bench testing the new one). If it isn't it may be a bad ignition switch. If you get to the point where the battery and starter are good, we can talk about ignition switch testing.

Do yourself a favor and double check your fuses are all good. Check any and all - I doubt this is your problem, but it's free and easy to do.

mgracia15

IT WAS THE STARTER

I had it towed to a trustworthy mechanic and he found that the starter was the source of the problem. Also claimed that my battery may need to be replaced as well since it looks very old. The cost of the repair was quoted to be $350 for parts and labor of the starter. Is this price fair to y'all? Or what do you think?
Also, what battery would y'all suggest I invest in? And if you know, what brand for a starter?