Jeep starting up weak

[jnaut]

The 3.7L naturally idles rough, so if the new battery doesn't fix that..... then the rough idle is definitely normal.

A little rough. But pretty smooth right after a plug change! (attn)

 

[yellocoyote]

A little rough. But pretty smooth right after a plug change! (attn)

And a seafoam treatment!

Sorry... back on topic.

 

[KJ zGal]

Or maybe spark plugs if it turns out to be a non-electrical issue? I noticed mine started better after I changed them...

 

[Clyde Frog]

Or maybe spark plugs if it turns out to be a non-electrical issue? I noticed mine started better after I changed them...

Yeah but they're a (censored) to get to. I dunno if I have enough patience to try

 

[yellocoyote]

It's not that difficult - I've changed mine 3 or 4 times now since I've had the KJ.

 

[ThunderbirdJunkie]

Or maybe spark plugs if it turns out to be a non-electrical issue? I noticed mine started better after I changed them...

Spark plugs won't affect how fast the engine cranks over during starting.

Just get the battery.

 

[tjkj2002]

Plus, Autozone can scan to check the battery and alternator for free.

They can check the battery but the charging system they can not properly test,and yes that means the alternator.Only the DRBIII or StarScan can properly check the KJ's charging system as it is 100% controlled by the PCM.

Yes the KJ uses the PCM---PowerTrain Control Module---- and not a ECM.

 

[KJ zGal]

There was only one of the 6 that I really had trouble with, the back left I think it was...other than that they're not TOO bad (unless you're short like me and have to use a chair or sit on the top of the fender to do it lol!)...but yeah, worth checking out anyway if they haven't been changed in a while.

 

[TigerClaws]

Just put your current battery on charge for 6-8 hours ...

I have to charge my battery once in a while because i do not run the jeep enough ... im 10 minutes from work, and that makes my battery go dead faster because the alternator has no chances to recharge the battery. 10 minutes is way out of his league so.

 

[kb0nly]

Sounds like another owner due for a new battery. The KJ does weird stuff with a weak battery. The CEL was probably battery related one way or another, there has been owners on here getting random CEL's and then they had a battery go, replace the battery and all the other gremlins go away! Low voltage can really screw up the systems in the KJ, as well as most modern autos...

The service message on the overhead console, or EVIC as we call it, is a settable reminder for oil change, filter check, etc.. I set mine to 3,000 miles every oil change, the mileage is adjustable if you wanted to set it for higher if you run synthetic or such. But its just a reminder that you can program in the console.

So is it due for oil change? If so get er done! And if the plugs haven't been done yet, i believe you posted your at 71k, then get them replaced if you can't yourself. The difference in starting and idling quality plus fuel mileage is worth it. I replaced mine at about 54k, i bought the KJ at 45k and didn't have time until almost a year later to do it, well made time because i noticed the idle was a bit rougher than normal and i was loosing some gas mileage over when i bought it. Turns out it had the factory plugs in it and they were well worn, should be gapped at .040 and they were out to .065-.070, so definitely needed replacing. Put in some Autolite Platinums and gained a couple miles per gallon and the idle is a lot smoother.

Your KJ is just pouting and asking for attention!!

 

[LibertyTC]

I personally change out the plugs every 30k miles. The Kj's coils are hot and tend to eat the gaps quick.
I would fully charge the battery with a manual charger overnight and then take the kj in for a battery load test, it will pass or fail, one or the other.
If I was replacing battery I would go to Sears and get a die hard Platinum, or get the real AGM- 34-78- Odyssey PC-1500DT (dual terminal)
http://www.odysseybattery.com/batteries.html
There also is an inexpensive battery heat sensor pad below the battery, it would be a good idea to install a new one, when a new battery is installed

 

[karter]

Why not take a few minutes and clean the battery terminals , cable ends and also the ground connection .It's free and should be done on a yearly basis anyway .

 

[ridenby]

Did you get a battery?

 

[tjkj2002]

Why not take a few minutes and clean the battery terminals , cable ends and also the ground connection .It's free and should be done on a yearly basis anyway .

Stop using a lead acid battery and you'll not have that issue anymore.

 

[jnaut]

Stop using a lead acid battery and you'll not have that issue anymore.

Ok, I'll bite. What other kind of car battery is there?

 

[Jeep-I-Joe]

Ok, I'll bite. What other kind of car battery is there?

AGM (absorbed gas mat). It uses a fiber mat suspended electrolite rather than a liquid. Check out the link for more info. Beware, they cost twice as much.

http://www.dcbattery.com/agmtech.html

 

[LibertyTC]

Here is a nice AGM battery!
Pc-1500 (34-78 dual terminal)
http://www.odysseybattery.com/auto.html