Things are always running fine, until they aren't, huh?

My Jeep pretty much does fine on the flats.
It goes downhill just swell. (What doesn't)
But coming up a washboarded dirt road at a pretty steep grade (probably 8-10%) The car starts to sputter and lurch.

It also appears to drop gears and try to find itself where it belongs.
It throws no codes.
The electrical stays on.
I noticed one time that the fuel bell rang, and the gauge showed empty, when in fact, I had just filled up at a place I normally don't go.
I was able to continue. I shut the AC off, and just sputtered and learched the four miles home.

I also noticed that the sputtering was in sync with the bumps in the road.

My first thought immediately was bad gas, but then the cutting out on the bumps made me think way more than twice.

I threw a can of heet in it yesterday just for the Halibut. Drove it about 25 miles, until I came to the steep grade on the dirt road, and it started doing it again.

The battery connections look good, and right off the bat I didn't see any rat chewed wires in the engine compartment.

I replaced the CPS about 2 months ago. It showed a code for it when it was failing, and again, no codes now, it just says done. (I really hope it doesn't mean that!)

The only other thing that's even close to something new added is one of those insurance tattle tails that they entice you to use for a bit with the promise of lower rates. It plugs into the port below the dash, and it's plugged in tight.

As an aside, I've also had a turn signal problem starting back further. Sometimes they work, and sometimes they don't.
Not sure if this is in any way related.

So I got something going on...and I'd sure appreciate some suggestions on this.

Thanks,

Joe

I have a really steep hill that I drive on at least once a day and the speed limit is 30 mph. It is paved however, but I manually downshift to 2nd and proceed up it smoothly at 2000rpm and 30 mph. It's a neat winding tractor path that wasn't even paved until people started buying lots from the farmer and building $500,000 homes on about 15 years ago. It's a working dairy farm and people seem to like the manure smell! LOL! The guy seems to be making money. He has 7 huge solar panels on the farm now.

You probably have at least one loose electrical connection somewhere. Check the cable plugs for the PCM.

The turn signal flasher is quite a complex unit. It has 3 logic circuits in it, one for left, one for right, and one for hazards. My left signal refused to work but I found turning on the hazards and quickly turning them off, the left would continue to blink. I replace the multi-function switch and that didn't work so I had to replace the flasher. That was the problem, but it was a PITA to do! It also cost about $40.

As I said previously, the car doesn't show any codes with the on/off key method.
Might a parts store code reading show codes that I might not see?

Thanks,

Joe

A scanner that shows active data while running has the ability to show pending problems that might not have set a code yet. Usually a problem has to be active long enough for the PCM to record it. An occasional misfire won't unless it's long enough to effect the 02 readings.

Having said that, your problem should have set a code by now unless it's a loose connection. The problem is the PCM does not diagnose itself, only the data sent to it. A loose sensor plug will show as "loss of signal" whereas loss of power to the PCM won't. Because this problem just appears under load on a bumpy road says to me there's something loose somewhere.

A spark plug with an unusually large gap or cracked insulator may only misfire under heavy load, but that almost always set a code. If it's fouled with oil and cleans itself out, it may not.

Can you smell the smoke yet? I'm burning my brain trying to figure this out, that's why I'm rambling. Is this a 4.0 or a 4.7?

Aye yi yi.
A friend suggested that it might be the fuel pump relay, so he suggested I just switch it with the horn relay.
No help.
Took it for a drive, got about a mile and a half, and it sputtered to a stop.
All the lights and gauges still operate, except the fuel gauge light is on, and it says empty, although I know it has a half tank.
It will start, then die in about a second or two.

It is now showing code 0463, which online says: Circuit shorted to voltage between PCM and fuel gauge sending unit.

Please don't tell me that if the fuel gauge doesn't work, that the car thinks it's out of fuel and won't run.

Anyways, is there anything to do, or should I just have it towed to the shop?

Personally, I don't have what it takes to drop the tank, if that's what it needs.

Check the wiring to the pump. I believe you can get to the plug without dropping the tank. You may have a wire rotted off at the plug. That's what happened to my NSS, although all it effected was my reverse lights. HA! Loose connection! Probably the ground wire.

I found a small opening under the spare. Unfortunately, even with a mirror, there was not much I could see.
I put the ignition in the run position, and wiggled the wires with no results.

What kind of idiot designs these fuel tanks with no access to the pumps, and just who was the idiot that decided to put the pump in the tank in the first place?
I was just fine with the fuel pump being mechanical and visible right on the front of the engine.

There's just so many systems in cars now that go against a vehicle even running.

Much like an Explorer I had that had a "Lights out" module.
Great idea! It let you know if you had a headlight, or tail light out.
But if the module that told you your lights were out went south, your lights would go out!
It's like some sort of double redundancy redundance reduncer.

Fark!

The old mechanical pumps only supplied fuel at around 7 psi and injectors need around 50 or better. At that kind of pressure the pump needs to be cooled and putting it submerged in the tank was the best option. I personally think putting a 12-volt devise in an explosive atmosphere is stupid as well.