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NHWK05 02-24-2010 09:48 PM

More stalling/funky idle issues.
So in the past i have discussed how my jeep will stall (4.7 v8) much like the HEMI jeeps. It did not matter if the jeep was hot or cold, out side temp, or if it was a light or hard stop. The RPMs would drop real low to the point of a stall out.

Well a very well known master technician at a dealership told me to put just a little extra ATF+4 in the trans as the problem is supposedly caused by not enough fluid/pressure. so i tried it and Bam its been fine ever since.

Recently however i have noticed that upon immediate start and cold or hot start if i dont let the jeep run for at least 30 seconds or so and then give it gas while shifting in to drive or reverse it will start to bog down and almost stall out.

Ive also noticed while driving that it did not come to the point of stalling at a stop but the RPMS do drop very low some times when stopping and the jeep almost stalls out.

What the hell would cause the RPMs to drop so low upon a stop and what would make it want to bog down when giving it throttle right after a startup?

brent 02-25-2010 07:44 AM

Re: More stalling/funky idle issues.
I noticed when my fluid levels were low it seemed to jump, but right now they're spot on. There's another thread with the same issues I started with the same problems. Our engines are different sizes but I think mostly the same theories and practices apply.

HemiPower 02-25-2010 04:58 PM

Re: More stalling/funky idle issues.
Do you have the latest engine and transmission software, I have an 2005 Hemi and just last week it was updated with the latest flash now my idle is a lot better and so is all round drive ability.

NHWK05 02-25-2010 06:35 PM

Re: More stalling/funky idle issues.
I had it "reflashed" a few months ago. I can go and try it again.

jcostri09 02-25-2010 06:47 PM

Re: More stalling/funky idle issues.
A friend of mine has a 4.7 WK and had a similar problem. Turned out his air filter (stock) was clogged up. He replaced the filter and was good to go.

HemiPower 02-25-2010 07:13 PM

Re: More stalling/funky idle issues.
Another thing I had a rough idle at startup, and it came up with a P0300 random misfire. Ended up replacing all 16 plugs with oem champions and unplugged the battery to reset and that solved the code and weird idle at start up. The plugs had about 40,000 on them.

NHWK05 02-25-2010 07:50 PM

Re: More stalling/funky idle issues.
Thanks guys.

I have a K&N drop in filter for now and i changed my spark plugs over the summer.

AcidCold 02-25-2010 08:47 PM

Re: More stalling/funky idle issues.
Maybe your intake swallowed a Honda?

Nand12 02-26-2010 04:49 PM

Re: More stalling/funky idle issues.
Might wanna check/clean IAC assembly because this sounds exactly like a common problem that Ford Explorers had and what was happening was that the IAC plunger was gummed up with carbon and sticking open. When you shift into drive, my guess is that the IAC plunger is not closing which means that you're getting more air and not enough gas (because the PCM assumes that the IAC plunger has closed and cuts the fuel accordingly). This could also explain why your engine dies as you come to a stop...the IAC assembly is supposed to gently open as you coast to a stop to start pumping air (you're no longer generating enough vacuum because your foot is not on the gas) and keep your engine running at idle.

maxst2 02-26-2010 05:34 PM

Re: More stalling/funky idle issues.
What type of plugs did you put in?

tig488 08-14-2010 10:57 AM

Re: More stalling/funky idle issues.
what happened with this. now mine is idling wierd when im stopped with the brakes on, but if i put it in neutral it idles fine.

NHWK05 08-14-2010 04:01 PM

Re: More stalling/funky idle issues.
I originally added the 1/2 qt of trans fluid per the mechanics reccomendation. After about 8 months it started to stall again. I checked the fluid level and made sure it was nice and red and not brown or burnt smelling and it was all right where it should be. I then added some lucas trans oil fix stuff. Not sure which it was an additive oil for any modern trans. I have it in the garage if you want to know what it is. I added that a few months ago and its fine ever since. I am going to get a trans service soon and will prolly have to add more after that as it seems this problem happens after a service because of a lack of oil.

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