Hi,

Strange happenings with the old beast yesterday. Driving down the freeway at 70, power suddenly dropped to nothing, engine still running but idling rough, no power, chuffing and missing big time. Can get forward motion, but 10 MPH and sounds awful. Let it sit at idle for a few minutes, starts running OK. Ran for another 30-40 miles fine, same thing happens again. Had it towed to a mechanic at 1:00 am. Gas tank at 1/4 full.

Once the mechanic arrived at 8:00, battery was dead (probably has NOTHING to do with the problem). No codes, replaced battery (bad cell) and test drove a bunch. Could not repeat the problem, so got back on the road. Same problem half an hour later. Waited a few minutes, started running better, so I drove the rest of the way home (300 miles!) like a little old lady, very easy on the gas, stayed under 70, and made it home OK. Filled tank about 50 miles after the last episode. Check engine light was on, only code is a misc misfire code.

Mechanic here at home can't find a problem, suggests plugs and wires (not the problem, but needs it anyway).

Fuel filter / Fuel pump?

Thanks in advance for your help! Steve in Costa Mesa.

 

Welcome to DF
Here is a TSB with information that may help?


DISCUSSION:
The following items are service procedure clarifications for the 1996 NS vehicle build and service variations:

VEHICLES INVOLVED IN RECALL #665 THAT REQUIRE FUEL TANK REPLACEMENT AFTER RECALL #665 HAS BEEN PERFORMED: Must have vapor canister hose harnesses (that were added as part of the recall service) removed. The new fuel tank will include revised rollover valves and a new vapor canister harness that can be attached directly to the metal chassis tube to the vapor canister. Cap the two open filler tube nipples (upper and lower rollover valve nipples on the filler tube as shown on page 10 Figure 14 of recall #665) with vacuum cap P/N 3580172.



VEHICLES INVOLVED IN EITHER RECALL #665 OR #670 THAT HAVE BEEN MODIFIED AND NO LONGER HAVE THE ORIGINAL FUEL TANKS: Still require the installation of the filler tube ground strap. Use the parts package and the service procedure for Recall #670 to install a filler tube ground strap. Dealers are to submit the recall claim using labor operation number for the recall that the vehicle is involved in to record the service completions and to provide dealer payment.

THE EXTRA 3/8" VENT TUBE RETAINER (SUPPLIED IN THE RECALL #665 PARTS PACKAGES) MAY BE TOO LONG FOR SOME OF THE INVOLVED VEHICLES: A change in production was made to the length of the retainer. Therefore, if the 3/8" retainer from the recall package can not be assembled, reuse the original retainer.

SYMPTOM/CONDITION:
Only 12-13 gallons of fuel are able to be added when the low fuel warning light first comes "ON" (normal is 16-17) or 15-16 gallons of fuel are able to be added when the fuel gauge reads "E" (normal is 18-20).

DIAGNOSIS:
Inspect the bottom of the fuel tank. If the fuel tank bottom is bowed upward or the "short fill" condition has otherwise been verified, perform the Repair Procedure.

PARTS REQUIRED:
Quantity
Part No.
Description

1

4883140
Tank, Fuel

1

4695227
O-Ring, Fuel Pump Module

1

4883322
Spacer, Fuel Level Unit



REPAIR PROCEDURE:
This bulletin involves installing a spacer on the fuel level unit and IF the bottom of the fuel tank is bowed upward installing a revised fuel tank.

Drain the fuel tank into an approved gasoline holding tank.
Record the radio station presets, disconnect and isolate the negative battery cable.
Raise the vehicle on an appropriate hoist.
Use a transmission jack to support the fuel tank. Remove the attaching bolts from the fuel tank retaining straps. Lower the tank slightly.
Clean the area around the fuel pump module and tank to prevent foreign material from getting into the fuel tank.
Disconnect the fuel lines from the fuel pump module by depressing the quick connect retainers with thumb and fore finger.
Slide the fuel pump module electrical connector lock to the unlocked position. Push down on the connector retainer and pull the connector from the module.
Using Special Tool 6856, turn the plastic lock nut counterclockwise to release the fuel pump module.
Remove the fuel pump module from the fuel tank. Cut and discard the O-ring seal.
Depress the retaining tab and remove the fuel pump/level sensor wiring connector from the electrical connector at the bottom of the fuel pump module mounting flange.
Insert a screwdriver between the fuel pump module and the top of the fuel level sensor housing. Push the fuel level sensor down slightly.
Slide the fuel level sensor out of the installation channel of the module.
Slide spacer P/N 4883322 into the installation channel so its "V"-shaped channel is on the wire side of the installation channel and the "V"-shaped channel of the spacer captures the fuel level sensor wires. The spacer should slide all the way to the top end of the installation channel.
Make sure the fuel level sensor wires are routed in the slot at the top of the back side of the fuel level sensor, then slide the fuel level sensor up into the installation channel until it "snaps" into place. Be sure the tab at the bottom of the sensor locks in place and the spacer is tight between the fuel pump module body and the fuel level sensor.
Connect the fuel pump/level sensor wiring connector to the fuel pump module.

Remove the three screws attaching the filler tube blocker and separate the blocker from the vehicle.
Disconnect the rollover valve harness to steel vent tube connection at the front of the tank.
Disconnect the fuel filter supply line from the steel fuel supply line.
Loosen the clamp on the filler tube hose at the tank connection.
Carefully remove the filler tube hose from the fuel tank.
Disconnect the filler vents from the filler tube by squeezing the retainer and pulling the connector off of the steel tube.
Lower the fuel tank slowly while feeding the vent lines through the frame rail to remove the fuel tank from the vehicle.
Remove the fuel filter attaching screw and transfer it and the fuel filter to the revised fuel tank (P/N 4883140). Torque the screw to 35-45 in. lbs. (4-5 Nm).
Insure the seal area of the fuel tank that is to be used is clean and install the fuel pump module into the tank using a new O-ring seal (P/N 4695227). Make sure the locating tab on the fuel pump module is lined up with the notch on the fuel tank.
Torque the fuel pump module lock nut to 40-45 ft. lbs. (54-61 Nm) using Special Tool 6589.
Attach the fuel filter lines to the fuel pump module by pushing the fittings onto the tubes until the retainers seat. Pull back on the connectors to make sure they are secure.

Place the revised fuel tank on a transmission jack and slowly raise it into position while feeding the fuel filler vent lines through the frame rail. Make sure the vent lines are not crossed on top of the fuel tank.
Line up the fuel filler tube hose with the fuel tank inlet neck and push it on.
Raise the tank up to the underbody and install the fuel tank retention straps. Torque the fasteners to 30-50 ft. lbs. (40-68 Nm).


Attach the filler vent lines to the filler tubes by pushing the connectors on until they are seated. Pull back on the connectors to make sure they are secure.
Torque the fuel filler tube hose clamp at the fuel tank to 25-35 in. lbs. (3-4 Nm).
Push the fuel filter supply line connector onto the steel fuel supply line until it is seated. Pull back on the connectors to make sure they are secure.
Attach the rollover valve harness hose to the steel vent tube at the front of the fuel tank.
Install the fuel filler tube blocker and torque the fasteners to 45-55 in lbs. (5-6 Nm).
Attach the fuel pump module electrical connector.
Lower the vehicle and refuel it with fuel drained into an appropriate holding tank.
Connect the negative battery cable.
Program the radio station presets and set the clock.

 

Thanks for the input. I'm not sure what to take from it - are you thinking the problem may relate to the tank? I only mentioned the fuel levels because it was the only thing (besides going slower) that changed between having the problem and not.

Thanks, Steve

 

You could have fuel delivery problem or some how something inside the tank could be shutting off the fuel. if that is what is happening.

 

Thanks for your help. I figured I'd replace the fuel filter and see if it happens again. Hopefully that's it , or I'll learn something that will make the cause more obvious. Anybody have any better ideas?