Jeep starting up weak

[Clyde Frog]

Over the past couple days, I've been noticing that my Jeep has been starting up really weak after sitting either for a few hours or over night. It does start up first try, but it sounds like it's barely doing so.

I haven't done anything differently as far as electrical goes aside from my new HU being installed about 3 weeks ago, but this starting issue has only started in the past couple days. My check engine light was on for 2 days and then went "magically" back off after we got a rain storm - wasn't running any differently before or after the CE light so I assumed something stupid like an O2 sensor is what was setting it off. Could this issue be related to that?

I'm guessing battery or alternator because it turns over fine and catches but starts up pretty weak.

Also, my "Perform Service" message has come on my overhead console. I believe it goes by a certain milage (every 6K or something like that) but any suggestions for what service it wants done/should be done? I'm just over 71K miles.

 

[BjBnet]

I'm guessing battery or alternator because it turns over fine and catches but starts up pretty weak.

I don't get it, what do you mean turns over fine and catches but starts up weak? It would be one or the other wouldn't it?

Also, my "Perform Service" message has come on my overhead console. I believe it goes by a certain milage (every 6K or something like that) but any suggestions for what service it wants done/should be done? I'm just over 71K miles.

first change the oil, then reset the console via the menu button

 

[Clyde Frog]

I don't get it, what do you mean turns over fine and catches but starts up weak? It would be one or the other wouldn't it?

It starts up, but it sounds bogged down and almost like it is barely catching/barely starting up until it finally gets it and then starts.

 

[HoosierJeeper]

Try the battery, can't hurt anyways.

 

[Marlon_JB2]

I know exactly what you are talking about. Get your charging system checked. It may be time for a new battery.

 

[Clyde Frog]

I know exactly what you are talking about. Get your charging system checked. It may be time for a new battery.

On average, excluding labor, what's a good battery gonna run me?

 

[Marlon_JB2]

On average, excluding labor, what's a good battery gonna run me?

Depends on what you want. $90 (Low End)-200 (High End Battery). You can put the battery in yourself and some auto parts stores will do it for free. Yeah it takes 5 minutes, literally.

 

[Atrus]

What Marlon said.

8mm wrench and a 10mm or 13mm (can't remember what the hold-down size is). You literally can swap it out in the parking lot, and I think Autozone will even do it for you.

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

 

[ThunderbirdJunkie]

Autozone also sells shit batteries though in addition to decent ones. Don't buy one of the shit ones

 

[Clyde Frog]

Any advice on some good company names? I keep seeing "red top" as a popular choice, but not sure who makes it.

I'm supposed to have it checked out Wednesday morning so I'll test my battery tomorrow with the voltage thinga-majiger (yes, that's a technical term) we have and see what readings I get. If they're normal, I'll see what the mechanic says it is and go from there.

 

[HoosierJeeper]

Optima Red Top.

Takes no time, except if you have to replace a cable like I did.

 

[jnaut]

You mentioned your CE light... you should pull a code just to see what the issue was... Even thought the light went off, it should still be in the memory for quite a while.

 

[Clyde Frog]

You mentioned your CE light... you should pull a code just to see what the issue was... Even thought the light went off, it should still be in the memory for quite a while.

I think my local AutoZone pulls codes for free. I'll stop in tomorrow and ask.

 

[ThunderbirdJunkie]

They do, but chances are the CEL was for A: an overheated battery, or B: low output voltage.

 

[Clyde Frog]

I don't know if it's because I'm used to the idle of the BMW or not, but my Jeep's idle almost feels like it's rough and a bit loud. Any correlation between that and the starting problem?

 

[ThunderbirdJunkie]

A weak battery will not supply the amperage the ECM needs, and the engine will run like crap

 

[Clyde Frog]

Ecm?

 

[ThunderbirdJunkie]

Engine control module.

Just go get a battery. O'reilley Auto Parts should have what you need in stock.

 

[Marlon_JB2]

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

 

[moparman]

And the roughness is somewhat intermittent.