I'm stumped....Stalling ++

[NotMyRenegade]

My apologies ahead of time if this has been discussed but I haven't come across similar issues. Jeep was running fine until battery died and ended up installing new alt/battery. Now having some issues. I will start with my wife stating fuel mileage is a lot better since new install.Well that tells me its now running lean....but no check engine light.So I grab the keys to go for a drive...yep...no check engine light but I notice at start up when the fan clutch engages a noticeable RPM drop and when it shuts off back to the norm. So I go for a coffee run and everything is good but when I'm waiting in drive-thru line it sounds like it wants to stall.On my way back home it did stall on me when I came to a complete stop.Starts no problem and no issues for the remainder of the drive.Now, before I start playing whack-a-mole ( as another member quoted in another post I read trying to find a solution ) what am I looking for....a vacuum leak? is it an a/c compressor issue? idle control sensor? MAP sensor?...its not the alt/battery cause it checks good...maybe because the jeep had no battery connected for one day waiting for the alt to arrive I need to reset the ECM??? I hate the fact that auto manufactures made new cars so complicated with all these unnecessary electronics that the common man has to have an auto degree to diagnose/repair their own vehicles.Oh...one more thing and this may be related..I had changed the PCV valve and air filter a couple months ago and noticed a vent hose on the side of the air box and that small filter was hard and crumbled when I removed it.Called the dealership to get a new one....no luck...didn't even know what I was talking about.Long story short I made my own using a Briggs and Stratton filter.Seems to work fine but there is quite a lot (to me) of oil?leaking from the box.Seems kind of excessive....not familiar with this.Cause for alarm??? Hope someone can shed some light on my problem because I don't really want the wife taking it to the mechanics because I know they will charge her for 4 hours of troubleshooting when they probably know what the problem is as soon as they see the situation.Any suggestions would be greatly appreciated.

 

[JRB]

I can share my experiences with mine till someone chimes in that is more helpful on the problem.

I've had the battery out/disconnected for over a week while working on it, I did not have any computer issues with that. For piece of mind and something simple, you can pull both battery cables off and short them out (tie them together, I wrapped a rag around the outside after that for piece of mind). In theory it lets go of any stored energy in capacitors, I've done it on mine when I was chasing airbag lights and trying to get my abs lights off after I broke a wheel speed sensor. It did not solve all my problems, but my jeep still ran fine after.

As far as the filter in the airbox, I cut down a tire shine applicator and fit it in mine. I'd say yours is more proper than mine, and mine has been working all right since I changed it.

Diagnosis would be whack a mole for me, checking the usual suspects of some of which you said, map, vacuum lines, see where fuel pressure is at, any pulleys starting to act up, etc. There's some helpful people on this site, hopefully they know what you're experiencing.

 

[LibertyTC]

What is the rpm drop/ reading when compressor engages ?
Wants to stall, try cleaning the IAC ( intake air control ) and related port. See post # 10 onwards- https://www.jeepkj.com/threads/idle-air-control-no-screws.44826/
Use a New Mopar IAC - if cleaning does not work.
Vent hose on the side of airbox, are we talking inside the air filter housing? Known as Sponge Bob? Photo would help there.
What year is your Jeep?

 

[NotMyRenegade]

Yes LibertyTC....Sponge Bob....****...so this morning I decided to check out the sponge and discovered some white sludge and the sponge was soaked with the sludge.So I replaced it with more B&S air filter foam and took it for a drive and no threat of stalling so now I am going to clean the PCV even though I just replaced it and I want to clean the lines and I noticed a schematic diagram for the emission control system and its showing crankcase filters at the ends of the PCV vent tubes.....huh?what?. So I am going to take the throttle body assembly off, inspect the IAC and clean or replace and with that out of the way hopefully I can get at these so-called crankcase breathers and hopefully be able to clean those up as well. On the emission control diagram I discovered something else I'm not familiar with...a proportional purge solenoid that the vacuum line from the throttle body connects to....what the....anyways....holey whack a moley......Oh yea....its a 2005 Renegade Trail Edition with the fog lights on the bumper and lights on the roof....the reason she wanted it....can't blame her...it is a nice looking Jeep.As soon as I find my digital camera I'll post pics....in the meantime thanks for the advice and will get back to tell you how it goes.Cheers

 

[LibertyTC]

Check /remove baffle inside the oil filler tube looking for yellowish sludge, caused by short trips.
The PCV lines can get packed with oil. Cleaning PCV with Carb cleaner is fine, once line is removed first-as long as it rattles, it''s good.
Be careful when twisting off /removing the PCV from filler tube, dont want to crack it at the side. So heat up the line first away from the PCV with a hair dryer for safer removal.
Are you using full synthetic engine oil-5W-30? Do you have this sludge present?
2005 factory service manual is here: http://www.colorado4wheel.com/manuals/Jeep/KJ/2005JeepKJServiceManual.pdf

 

[NotMyRenegade]

Thanks LTC....wasn't aware their was a baffle....and yes...I'm aware of the PCV valve as stated I changed it not that long ago....I actually learned not all PCV valves are the same....I purchased one from NAPA who is my part source of choice but learned that not all replacement parts are treated equal.Had to get one from dealership as the one from NAPA did not want to click in place....go figure....cost me double.Makes me wonder if the same goes with the IAC sensor is going to be the same.At NAPA that part is $130....guess I better call the dealer and see if they have one in stock and get a quote in the event I have to replace it.I have a feeling I'll have to as the one is question is probably the original.

 

[LibertyTC]

Tech Service bulletin with a larger PCV for a 2007- is still available today,yet lines will be a different set up see link below.

It was included in an over all kit that re-routed lines, which unfortunately seems to have been dis-continued now years ago.
The kit removed the small oil filler PCV- in favor of large PCV and new oil filler tube, with no PCV on the side.
This describes the Tech Service Bulletin..overall and on page 2 shows the larger PCV. https://www.jeepkj.com/threads/pcv-positive-crancase-ventilation-tsb.59367/

The IAC & port once cleaned, hopefully fixes the stalling.
Note the set up to break free The IAC. Use a penetrating fluid on the single IAC bolt.
It needs to have solid inward pressure applied, to break it free!