Bad battery?

[BigEarl325is]

I'm really not sure what's wrong with my engine. It's not a huge deal but it's enough to annoy me if I can fix it. My engine is constantly idling rough, never settling on the same idle speed. It drives me nuts. When I start the engine, sometimes it's smoothe as glass, other times it settles at like 500 RPMs and idles like crap. Then, sometimes when it gets really bad, I'll have it up there around 4000 then pull it out of gear, it'll drop its RPMs and it should catch around idle speed but sometimes it doesn't make it and it stalls. That's a little rare but it happens at least once every 2 weeks. Does anyone else have a problem like this. I'm told our Idle Control Valves never go bad but at this point, I'm not sure. I have brand new plugs and as far as I know my coil packs are in good condition. Is it possibly my battery not giving the coil packs enough juice? Is it possible that the coil packs aren't connecting to the plugs tight enough? Is it my alternator not charging the battery good enough. When I turn my lights on or put up my windows the RPMs drop hard if it's idling. All very strange stuff. Maybe it's my fuel injectors. If ANYBODY has ever had a problem like this, please help me out.

 

[Wadula]

i was thinking that your idle control valve gives up

or

the lamda sensor goes bad (the one that measure the exhaust and regulates rpm/fuel at idle

or

maybe the hot airflow whatever it is called

or

your coils.


I do not think it the battery as you can disconnet the battery when the engine is running, it will run through the alternator solely. at least in theory i think cause i never tried my own.

 

[mostwired]

By the way - it's not a good idea to try and disconnect the battery while engine is running. You may cause damage to your electrical system. [fake]

 

[Wadula]

that thought of course is only theoretically

 

[carcus]

Through some fuel injector cleaner...when was the last time you had a injector cleaner? Sounds like a fuel problem more than wire problem. When the tank is on empty, get some good injector cleaner......add it to an almost empty tank, then fill up after you drive a few miles. Fuel filter could be clogged also. Sometimes big particals can make it shake. Mine did the same last weekend. Injector cleaner cleared it up. Try the small things first.....baby steps....helps on the check book also. Let us know how it turns out. Also, sometimes you just need to HAMMER on the car to burn out the carbon. Drive it hard for a day. Blow out that carbon. Where do you get gas....do you run 89 octane minimum...are you hearing knock? Could also be water in the gas. Cheap gas. Heet will burn that out. Are you a stop and go driver? Get some highway miles on it....could be alot of things. Last time you had a tune up?

 

[BigEarl325is]

I buy gas from a respectable company, 93 octane ONLY. I've used fuel injector cleaner before I posted this. I've replaced my fuel filter about 5000 miles ago. I hammer on the engine daily (merge onto highway) and I drive 100+ miles on the highway every day. Brand new plugs about 20000 miles ago. I tried using my friends coil packs but they didn't make a difference. Still looking for suggestions but thank you.