Gas issues?....

[Original_MudButt]

In case you didn't see any of my earlier posts about this.....

'98 4.0 with 97k miles.....

Went to Goatfest and ended up with 35 gallons of rusty/watery gasoline in my RV.

I didn't want to throw away over $120 worth of gas, so I pumped out 5 gallons and ran it through a filter I bought at a boat shop. It was supposed to filter out all the water and any crappolla larger than .005"

I put 15 gallons of gas in the tank of the XJ then added 3 gallons of the filtered gas and a bottle of STP fuel system treatment I had lying around.

Jeep hasn't run right since. Every morning it cranks (what seems like) forever before it finally fires. When it does, it sounds like it's only running on 4-5 cylinders for about a minute and idles like crap.

It just doesn't seem to have the pep it had before and the gas mileage seems a bit lower (though I haven't checked so can't back it up with actual numbers).

Now when the gas light comes on telling me to fill up, whenever I turn left it dies for a 1/2 a second or so and then comes back. It never did that before.

The exhaust smells..... Smells like....Well, like burning rusty water....

So far:

No CEL.

I have been through 3 full tanks of gas (the first one of course had the 3 gallons of bad gas and the STP)..

Twice I have bled off the fuel rail (don't ask why, I really don't have a reason, just hoped it would help).

Every chance I get I flog the heck out of it... (Poor man's tune up).

Up next:

Borrowing a fuel pressure gauge to check the pressure in the morning. Even though I wait a few seconds with the key on before cranking it, it acts like it did when I had a leaky fuel filter.

Going to pump out as much gas as I can from the tank with a hand pump. I know water settles on the bottom, there may still be some water in it. I'm trying to fix this without dropping the tank. I've got an OakieTerry tank skid, so dropping the tank is like a weekend project.

Maybe try some HEET?

Anything else I should try?

Could the bad gas have screwed with the MAP sensor?

How about plugged injectors?

I'm leaning towards plugged fuel regulator and or injectors.

Any help here would be appreciated.

 

[ParadiseXJ]

Maybe try some HEET?

Anything else I should try?

Could the bad gas have screwed with the MAF sensor?

How about plugged injectors?

I'm leaning towards plugged fuel regulator and or injectors.

Any help here would be appreciated.

I'd try to get as much gas out as I could, then put in ~3-5 gals with a whole thing of HEET. I had to do this on the MJ after it had sat for a year or so with the fill tube missing.


1. Yes on the sensors

2. Yes on the injectors

3. Regulator, doubtful. I'd look more to the injectors or the filter element swelling up with water and becoming ineffective and sluggish. Pull a spark plug or two and see what you find in the cylinders.

 

[Original_MudButt]

3. Regulator, doubtful. I'd look more to the injectors or the filter element swelling up with water and becoming ineffective and sluggish. Pull a spark plug or two and see what you find in the cylinders.

On mine the regulator and filter are integral. Hopefully the pressure test will give me some insight on those.

I forgot to add checking the plugs to my to-do list. (Don't know why we can't go back and edit our own posts after a certain period of time....)


Thanx....

 

[Dest]

Now when the gas light comes on telling me to fill up, whenever I turn left it dies for a 1/2 a second or so and then comes back. It never did that before.

This has always happened to me, just assumed it was the gas going to one side of the tank.

 

[Original_MudButt]

This has always happened to me, just assumed it was the gas going to one side of the tank.

Well like I said, it never happened before the bad gas. My light comes on at 1/8 tank. That's about 2 gallons.

It's annoying.....

 

[joe_peters]

Rather than HEET, run SeaFoam through the tank.

 

[birchlakeXJ]

Heet is really just isopropyl alcohol. IF you are running 10% ethanol, you have PLENTY of alcohol in your gas and Heet is of no need. Gotta think that Heet sales have dropped off substantially in the past years don't you think?? In the old days, I kept a bottle of HEET with every vehicle. In those days, fuel line freeze ups were extremely common. Not so much any longer.

Seafoam is good stuff. A strong stoddard solvent and some isopropyl alchohol. Worth a try for $6.00 or so.

Gotta tell you but that STP is worthless. Save your money.

Testing fuel pressure is never a bad idea. For a 98, you should have 49 psi plus or minus 5 psi.