Jeep Cherokee Limited 1996 Fuel Problems

Jon did pass the time by typing:

Hello.

Do you have the OEM fuel cap or an aftermarket one? Using an aftermarket cap can cause this because it won't vent the fuel tank properly.

Think of it this way. As you drive the engine burns petrol, the petrol leaves the tank and creates a vacuum. If that vacuum gets too big the system won't work properly and the jeep starves for fuel.

Next time this happens, hop out and take the cap off and put it back on again. See what that does.

Did anyone pump the tank dry to get rid of any water in it? If there is water in the tank, the fabric fibers in the fuel tank "screen" filter will swell up as it absorbs that water. It takes some time, depending on how much water is in the tank, before it starts blocking fuel flow enough to affect performance. Then when the engine is shut off or the fuel pump is no longer pushing as much of the water-contaminated fuel through the fabric, the fibers shrink and pass the fuel again.

That fabric in the filter swells up and reduces flow INTENTIONALLY to prevent excess water from getting to the fuel system. That's been done since carburetor days.

Water in the tank may not be from contaminated fuel sources. It could condense in the tank due to temperature fluctuations.

What absolute utter nonsense...

This "fabric" as you call it is Nylon.

Nylon doesn't swell in the presence of water.

If he had water in his fuel, the problem would be there all the time and would effect the injectors (fuel delivery) long before it would effect the fuel supply system (as evidenced by his loss of fuel pressure).

Odds are, since the original repair took the cheap route, he has another failing fuel pump.

-Brian

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But despite commenting about nonsense, your reply didn't answer the question. Did anyone pump the tank dry, to get rid of any water in it?

Take it from one who found out the hard way. Had similar problems, which did not go away until the tank was drained. An estimated one inch of water was in the bottom of the tank.

I do not know what type fiber was used but the "sock" filter in the fuel tank is designed to block water intrusion. Says so, somewhere in the pile of Chrysler shop manuals accumulated since my first one in 1968, for a Slant Six Valiant.

It should be pretty obvious that I'm not Grant, and I'm not posting from the United Kingdom.

What water? The OPs symptoms do not exhibit characteristics of water contaminated fuel, i.e., he has to drive 1.5 -2 hours before it occurs.

That's okay, I'd prefer to not believe someone who claims that a nylon inlet filter will swell in the presence of water.

Actually, it is not. Matter of fact, two weeks ago I changed out the original fuel tank sending unit in a 1967 Coronet 500 for a customer, the inlet screen used back in the 60s is coarse enough to just about pass #2 gravel.

Read the subject line.... It's 28 years later and it isn't a slant six Valiant, and besides, you're wrong anyway as evidenced by the stated fact that his fuel pressure is dropping to 20-25 PSI during the problem.

and later followed it up in another message with more rudeness and conceit and outright bad manners:

and then:

No, Neil. YOU are wrong to behave this way. The original poster would not have said what he did, if he didn't have something happen with his car that backs up what he wrote. If it helped him, it might help the rest of us, too.

Here we have a group where we are supposed to be helping and suggesting ways to get our cars to run better, and we have this Know-It-All blowing his self-centric and self-righteous bovine scats. If it makes him feel better, he must be a very small person indeed.

I have refrained and will refrain from using profanity, but I do have to conclude that you must have gotten a batch of bad drugs. Go hide under a rock.

VF

Screw the facts as long as we all feel all warm and fuzzy, right?

Do you believe that nylon will swell when exposed to water?

Ummm, last time I checked, my mother died in 1989.

Yeah, his 1968 Valiant. Not that I have anything against Valiant's, I've owned two, and a Duster also.

But I digress... If it's water in the fuel tank, why does it not pose a problem until the vehicle is driven for an hour or so?

Is it 'time delay' water?

To what, follow a wild goose chase?

By pumping out our fuel tanks? Do you have the slightest idea what a logistical nightmare that is to accomplish? 'Splain to me how you're going to get any pumping device or hardware past the roll-over check valves that are incorporated in the fuel system, and the fuel filler tube to be precise?

Look moron, I've been doing this for a living for over 30 years and and from Poon's descriptions, can assure you that I have a lot more working familiarity with this Jeep than he does no matter how tall of a stack of service manuals he possesses.

Oh, I'm crushed.

Is that the standard explanation for when someone disagrees with someone else? Sorry to disappoint, but I do not use drugs, but feel free to share -your- experiences with them when you have some free time, m'kay?

I'm guessing that you're posting from the Jeep group. How prophetic that your closing statement should lend such credence to the old saying, "when the only tool you have is a hammer, every problem begins to look like a nail." Works for both you and Poon.

What happened?

Here I go, posting a message in response to Neil the Stuck-Up One and his self-centric and self-righteous bovine scats. But when I go to retrieve the day's messages from my mail server, all of Neil's messages are GONE from the newsgroup. Every one of them.

Darn. His magnetic personality and blatantly overgrown self-image was such an inspiration to youth gangs and drug dealers and pimps everywhere.

VF

I'm truly sorry.

I've indeed been behaving with rudeness and conceit and outright bad manners.

I have indeed been self-centric and self-righteous.

I have called people "moron"

I have been inconsiderate of other people on this newsgroup who want to know and learn and not just listen to me boasting about how great I am.

Let me explain. I'm really a little weenie. If any of you were to meet me face to face, and argue with me, I'd run off and go cry in a corner. On the Internet I can act and behave like the Big Man I so much want to be. But I let myself get carried away and as I said, I am truly sorry.

Neil Nelson

A forged post, how absolutely original.

What's next?

Paint graffiti on my garage?

Burning dog poop on my front porch?

Ring the bell and run and hide in the bushes?

Prank phone calls asking for Prince Albert in the can?

Hi again

I just to say a quick thanks to the replys! I have been bush for the past month and thus dont have internet access! On the points :-

- OEM fuel cap - good point and yes I have an aftermarket fuel cap on, and did think of the pressue issue, on the second ocassion I did stop and undo the cap. There seemed to be not pressue build up in the tank

- Rechecking the fuel filter, I will do this next service and let you know what they find!

BTW I have completed a further 10,000kms since this last message and haven't had any problems at all - and I've been on some nasty tracks...

Thanks jON