Shifter not working equals bucking and stalling?

[justfixedthat...]

About 3-4 weeks ago my shifter wouldn't move to Park, I had to slam it forward. This happened intermittently maybe 3 times before...

about two weeks ago I was going 50 MPH and my jeep bucked. I reproduced the way it felt in a parking lot by going slowly, and very quickly (without taking my foot on the gas) shifting into Neutral and back into Drive. So this made me think the Transmission had slipped. This happened one more time as I exited the freeway, and that night it started fine in a parking garage but immediately stalled as I went down the ramp. It wouldn't start for about 20 minutes but finally did, without me doing anything special to it. I later checked the ATF level; it wasn't low but I put some in just in case. I now suspected the fuel pump. Put a new one in a week ago, lightly bucked again while on a 30-minute drive, stalled on a side street and restarted after a few tries, then stalled again after I got all the way back home (and wouldn't restart). I could tell it was the starter so I opened it up and cleaned it, and it started right up (I have a dual remote oil filter and the hoses leak right where they connect to the block, so the starter gets oil soaked).

Had to drain the oil today when fixing the leak, less than 2 quarts of oil came out, so it was very low (oil pressure gauge/sending unit doesn't work). No new codes (I've had an evap leak code for a while).

On this forum I've read:
Crank Position Sensor
Throttle Position Sensor
Coil pack (=bucking and stalling)
Connections (battery terminals, grounds, wiring harness)
Fuel pump
Idle Air Control
ATF needs to be 100% full

And I've read:
Turning off w/o sputtering = sensor
But:
Bad sensors throw codes

So, problems shifting into Park, almost no oil, bucking, oil-soaked starter, and random stalling. Presumably the starting issue can be ruled out as oil soak, but can this also cause stalling and bucking (maybe oil on grounds, sensors, etc)? Can the CPS cause intermittent stalling and bucking? Can low oil cause stalling and bucking? Is the problem shifting into Park related to the problems that started a week later for the first time ever??

Hope I've been clear. Thanks in advance for any advice or experience.

 

[AndyG]

Man you have so much going on I don’t know where to start....but consider this-

The remote oil filter that is supposed to extend engine life has you down to two quarts. Do you see where this is leading? A 4.0 is so tough it barely needs one oil filter.

If it were mine, all that comes off, it all gets degreased and contact cleaner and dielectric grease where it got soaked, the transmission linkage and wiring to it really needs checked closely...by the time you work through that you may have some light on the situation.

 

[justfixedthat...]

Trying to figure out how to use this forum

 

[justfixedthat...]

Excellent point, the engine just pushed through pretty much anything. The remote dual filter is mounted under the front passenger fender to allow easy frequent filter changes, ended up being more trouble than it's worth. I screwed a new filter into the block for now to stop the leak.

So you're saying the oil may have leaked onto some important parts? I opened the starter and cleaned it. Could the transmission wiring be oily as well?

A neighbor told me that the plastic piece in his shifter (not a jeep) broke and it caused bucking and stalling in his truck. He also suggested a vacuum leak could do that (and there's a whistling coming from the throttle body where it's bolted to the intake- happens when I take my foot off the gas). What's your opinion with that in mind?

 

[AndyG]

Excellent point, the engine just pushed through pretty much anything. The remote dual filter is mounted under the front passenger fender to allow easy frequent filter changes, ended up being more trouble than it's worth. I screwed a new filter into the block for now to stop the leak.

So you're saying the oil may have leaked onto some important parts? I opened the starter and cleaned it. Could the transmission wiring be oily as well?

A neighbor told me that the plastic piece in his shifter (not a jeep) broke and it caused bucking and stalling in his truck. He also suggested a vacuum leak could do that (and there's a whistling coming from the throttle body where it's bolted to the intake- happens when I take my foot off the gas). What's your opinion with that in mind?

Yes, check every hose ...You can spray a little starter fluid around the intake and you’ll know if somethings going on if the engine revs

 

[justfixedthat...]

Yes, check every hose ...You can spray a little starter fluid around the intake and you’ll know if somethings going on if the engine revs

Got some oil today and had them check the battery/alternator. Battery was bad. But on the way there I noticed the Jeep shuddering. What it felt like, and I know from experience, is the jeep was only using 4 or 5 cylinders. I wonder if I've been looking at a bad coilpack this whole time.

 

[AndyG]

Got some oil today and had them check the battery/alternator. Battery was bad. But on the way there I noticed the Jeep shuddering. What it felt like, and I know from experience, is the jeep was only using 4 or 5 cylinders. I wonder if I've been looking at a bad coilpack this whole time.

Dont rule out the catalytic converters

 

[AndyG]

What year is it

 

[justfixedthat...]

Dont rule out the catalytic converters

I got a 'pending' code the other day related to the catalytic converter. Balls. Is it clogged out of nowhere like that?

 

[AndyG]

I got a 'pending' code the other day related to the catalytic converter. Balls. Is it clogged out of nowhere like that?

Get it up to temp at night and raise the hood and see if they glow...the media basically begins to fail and breaks apart and moves around , which gives random readings to the system also.

 

[justfixedthat...]

Get it up to temp at night and raise the hood and see if they glow...the medial basically begins to fail and braks apart and moves around , which gives random readings to the system also.

Okay interesting. I'll check that out.

 

[AndyG]

You will hear a weird rattle standing beside it , sort of resonates down the muffler, and sometimes little air flow at the exhaust or a metallic smell.

They tend to fail quickly, what happens is the media breaks up, then it gets red hot, which accelerates its’ own self destruction.

Also watch for a wire on something hot and bad grounds.

 

[justfixedthat...]

You will hear a weird rattle standing beside it , sort of resonates down the muffler, and sometimes little air flow at the exhaust or a metallic smell.

They tend to fail quickly, what happens is the media breaks up, then it gets red hot, which accelerates its’ own self destruction.

Also watch for a wire on something hot and bad grounds.

New coilpack solved it. Misfiring was making it run rich causing the pending catalytic converter code. But I'll go over everything to double check it anyway. Thanks.

 

[justfixedthat...]

You will hear a weird rattle standing beside it , sort of resonates down the muffler, and sometimes little air flow at the exhaust or a metallic smell.

They tend to fail quickly, what happens is the media breaks up, then it gets red hot, which accelerates its’ own self destruction.

Also watch for a wire on something hot and bad grounds.

Correction: The coilpack fixed the sputtering and lack of power. Died today on the freeway and gave a 0320 code. New crankshaft position sensor fixed the jerking/stalling.

 

[AndyG]

Correction: The coilpack fixed the sputtering and lack of power. Died today on the freeway and gave a 0320 code. New crankshaft position sensor fixed the jerking/stalling.

Atta boy, the engines in these far outlast the management systems.