Quits at highway speeds every few miles

My 2000 grand Cherokee v8 4x4 has just over 100k and lately quits running at highway speeds. It will not crank up immediately and the fuel gage is past empty. After a few minutes the fuel gauge will read a little above empty and it will start right up. This seems to occur more often when ever I get below 1/4 tank or less. I took it to the dealer and they indicated they needed to put a new computer in it before they could even begin to trouble shoot it. Sounded costly to me, so will try checking a few thing myself.
Then yesterday it quit several times (yea about 1/16 tank) today, same waiting until the gauge moved then started. Got home, then this morning the thing is completely dead. Nothing. no power at all. The battery is nearly new. Seems electrical to me being the thing only starts up after the fuel gauge decides to move, otherwise it just cranks. Now it's dead. Any ideas on where to start? Thanks in advance.

First, fully charge the battery.

Second, clean all grounds and battery cables.

Third, have the battery load tested (free at most auto parts stores).

Third, have the alternator voltage/amps tested (free at most auto parts stores).

Fourth, if the all of the above checked/repaired and OK, and you still have the problem, then you have eliminated those as the cause and can get started on detail testing.

If you don't do the above test/repairs first, then you ain't going nowhere.

Good Luck.

Dealer's computer thing is a scam. Do the stuff Joe says. Also, if you have a voltmeter, check the battery. It should be at least 12.5 volts with motor off. When motor is running, it should be about 13.5. If not, get the alternator tested for free at Autozone, etc.

I've had many mechanics say that Jeep's and Dodge's are very sensitive to bad electrical hookups...Like Joe said start there
I put a new Battery in my fathers 99 XJ it would start fine but would not run unless I was giving it throttle...just dirty terminals, didn't even look that bad.

----See Joe's Post #2---

(Tip-Fuel pumps are $$$ and a pain! fuel pumps are cooled by the fuel in tank and should last longer if you keep it above 1/4 tank. the very last bit of fuel carrys more crud along to mess with pump and fuel filter. Try to stay above 1/4.)

-the info in Joe's post above, about the battery and grounds, is Very True. (Auto electronics often get REAL shaky if 12 vdc is weak.)
-Batterys are just like other parts-may go bad right after install, suddenly or slowly.
-it may be that some part is only bad while hot.

Suggest:
-Fuel above 1/4.
-Get the grounds / battery posts clean, as Joe's post.
-Then have the batt&charging system tested, as Joe's post.

Good Luck!

Thanks for the suggestions. We shall get the battery tested and check all the connections as joe indicated. I believe when we recently replaced the battery the terminals were cleaned, but probably not the other connections.
I will let you know how everything turn out.
thanks again

T

Ask Autozone to also do the Code Read/Scan Check. It may have a code show up to help find problem. Its also FREE. and only takes a minute to check computer and sensor stuff.
-Make note of any codes they find (usually 4 letter/number)-

orange

Not to run below 1/4 tank is also a good idea. When a fuel pump sucks air, it hits higher RPM's than it was designed for and can damage bearings in the pump. This is a common failure mode for electric pumps.

btt

Might also want to check out http://www.nagca.com/
Its the Grand Cherokee specific site.

Update, Changed CPS (new), replaced the battery terminals, New Battery, cleaned grounds I found, filled tank to 3/4. During test drive doing 40mps it quits, I feathered the accelerator a little then before I coast to a stop it start running again. Go another 3 miles and it dies at a stop light. No start, and while trying to start it the gas gauge reads less than zero. After several tried the gas gauge now reads 3/4 and it starts right up.
Go another 2 miles it quits again and this time the Security Key light illuminates. Same problem, no starting immediately, fuel gage below zero, then after maybe a minute the fuel gage reads 3/4 and it starts.
Stop at Autozone, no codes, shows system is fine.
It quits a couple more time and then I try the manual code process of turning the key on three time and the odometer code is "done".
Any ideas of where to go next.
Thanks guys

This is the Grand Cherokee Limited 4x4 with the 4.7 V-8 with about every option available.

Bad ground at fuel tank. The gauge going dead and no fuel says both lost there ground connection.

Do you know if you can get to the fuel tank grounds without pulling the tank down? Also, in another post is was stated "on the 2000 grand cherokee the fuel gage gets is ground thru the PCM. I have not tried pulling the PCM but maybe the wires to that are suspect some how. Suppose?

MAY POP said:

Bad ground at fuel tank. The gauge going dead and no fuel says both lost there ground connection.

Click to expand...

His tank is plastic, so there is no ground strap on it. The ground will be directly to the fuel pump.

Texgking said:

Do you know if you can get to the fuel tank grounds without pulling the tank down? Also, in another post is was stated "on the 2000 grand cherokee the fuel gage gets is ground thru the PCM. I have not tried pulling the PCM but maybe the wires to that are suspect some how. Suppose?

Click to expand...

You could start with a visual inspection on the fuel pump, but it is on the top of the tank and I don't know if you can actually get up there to see anything with out dropping it.