4.7 V-8. In the engine compartment on top of the drivers side wheel well, there is a sensor mounted with a hose coming out. The hose has got disconnected from its mate and I can not find the mate to plug it back in. Please Help. Thanks.

Since it sucks air (plenum vacuum)
my first wild guess, would somebody played with
the EVAP purge valve,,now all asunder.
no photos posted the blind so,,, expect wrong answers.

the service manual covers this topic fully
the valve if not missing has electrical connector top rear of
engine,
and 2 vapor hoses, top bottom of valve.
seen here

https://eautorepair.net/Marketing/Default.asp

The P1405 trouble code on a 1996 Mercury Tracer indicates an issue with the differential pressure feedback electronic sensor circuit (DPFE). The DPFE sensor is located on the driver's side of the engine compartment, mounted to the firewall.
To locate the sensor hose, follow the black rubber hose that connects to the sensor. The hose will lead to the EGR valve, which is located on the intake manifold.
Unfortunately, I am not able to provide pictures, but a quick online search may yield helpful visual aids.

Follow the top and bottom radiator hoses. Goes goes to the thermostat in a round about way which is right on the top of engine behind the EGR valve. Bottom hose goes right to the waterpump, easy access from underneath. The temperature sensor is located on drivers side mid engine. Look through drivers tire wheel well, you can see the sensor, brass fitting. A note, the top hose where it's attached to the thermostat is metal....tends to rust out, just get a new one and snake it back through there.

if you follow the big hose that comes off the left hand side of the intake manifold it leads downward to the side mounted intercooler. The MAP sensor is bolted onto the inner side of the intercooler. You have to unscrew the inner wheel well cover on that side and remove the front fender to get in there to the intercooler area. You can take the front wheel off or turn it full one way to get better access. The intercooler sits on the side of the car and fits between the turbocharger (mounted on the back of the engine) and the intake manifold. I'm sure there's a diy somewhere - probably a DIY for changing boost hoses. Last edited by AgGTI; 10-17-2010 at 04:13 PM.

Your power steering pump is located in the forward portion of your engine compartment (drivers side). After finding it there are two lines going out of it (they look like a black water hose). They go to your steering box. Remove the hoses with the appropriate wrench then remove the mounting hardware (2-4 bolts it should come right out after the mounting bolts are removed.

Replace the idle air solenoid. This sensor controls airflow into the engine to regulate idle speed. You will find the unit around the throttle body. Unplug the electrical connector and remove two or more mounting screws or bolts using a Phillips screwdriver or ratchet and socket.
Step 2Unplug the electrical connector to change the EGR solenoid. This unit controls the introduction of exhaust gases back into the engine through a valve. They come in different configurations. Depending on design, vacuum hoses may be attached to the unit or to the assembly if they share the housing with other components. You may find the solenoid on top and to one side of the engine or by the firewall. Unscrew the mounting bolts using a wrench or ratchet and socket, and disconnect the vacuum hoses.
Step 3Remove the vacuum hoses and unplug the electrical connector to remove the canister purge solenoid. This solenoid uses vacuum flow to carry fuel vapors from the fuel tank into the engine for burning. This small unit may comes in different configurations. Some are cylindrical in shape and may be located almost anywhere around the engine compartment. Follow the vacuum hoses connected to the back of the throttle body to find the unit. Some purge solenoids may be mounted in place with a bolt while others may be just hanging loose on the engine compartment.

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-- locate where the air conditioner blower box is attached to the passenger side of the firewall – see photo #1 – look to the immediate right at the top of the gas pedal arm

-- condensation flows toward the front of the vehicle through the firewall at the leftmost edge of the air conditioner blower box – drain channel
-- open the hood and stand next to the front wheel on the driver's side
-- look down at the firewall over the battery and to the passenger side of the brake master cylinder – see photo #2

-- locate the small diameter metal tubes running horizontally and attached to the engine compartment firewall
-- locate the hole in the engine compartment firewall panel behind the small diameter metal tubes
-- this hole leads to the drain opening in the air conditioner blower box mounted in the passenger compartment
-- follow the brake tubes as they run from under the vehicle and turn toward the front wheel on the driver's side
-- locate the hole in the engine compartment panel behind the brake tubes
-- insert a short length of stiff wire into the hole through the engine compartment panel to unblock the drain hole

REMOVAL

1. Disconnect and isolate the battery negative cable.
2. Remove the engine fresh air housing inside the engine compartment.
3. Disconnect the washer hose at the in-line connector forward of the cowl grille so that the in-line connector remains with the washer hose from the fresh air plenum.
4. Disconnect the washer hose from the hose clip located on the front fender side shield.
5. Remove the filler tube screw.
6. Hoist and support vehicle on hoist or jack stands.
7. Remove the right front wheel and tire assembly.
8. Disconnect the left right front wheelhouse splash shield and move aside.
9. Drain washer fluid from the reservoir and into a suitable clean container. This can be done by disconnecting the windshield washer hose from the front (outboard) washer pump and allowing the washer fluid to drain into a container through a temporary jumper hose connected to the front washer pump.
10. Disconnect the electrical body harness connectors to the washer pump motors and the fluid level sensor. Slide the red lock on the connector to the release position, then, depress the black tab and pull the connector off the pump or sensor.
11. Remove the two reservoir mounting screws.
12. Disconnect the reservoir from the body mount by raising the reservoir upward slightly and then down so that the reservoir filler neck and front washer hose pull through the opening in the front fender side shield.

INSTALLATION

1. Push filler neck and front washer hose through the opening in the front fender side shield. Connect the reservoir to the body mount by lowering the reservoir down.
2. Install the two reservoir mounting screws. Torque screws to 8.5 - 11.3 Nm (75 - 100 in. lbs.) .
3. Connect the electrical body harness connectors to the washer pump motors and the fluid level sensor. Slide the red lock on the connector to the closed or locked position.
4. Assure that washer is properly routed to prevent pinching and possible inoperative washers.
5. Connect the left right front wheelhouse splash shield and move aside.
6. Install the right front wheel and tire assembly.
7. lower vehicle from hoist or jack stands.
8. Install the filler tube screw. Torque screw to 8.5 - 11.3 Nm (75 - 100 in. lbs.) .
9. Connect the washer hose to the hose clip located on the front fender side shield.
10. Connect the washer hose at the in-line connector forward of the cowl grille.
11. Install the engine fresh air housing inside the engine compartment.
12. Connect the battery negative cable.
13. Verify system operation.

I have an 89 s10 blazer with the 4.3 tbi. the oil filter is a remote oil filter. there are two hoses running from the engine to the filter, which is located in the engine compartment in front of the left front wheel. it's mounted to the side.

Rear washer pump is located near bottom of washer reservoir, below the left front wheel house extension and between left inner and outer fenders. Have some operate the rear washer switch while you listen in this area to find out if the the pump is running. The hose from the pump routes up along side the reservoir filler neck, into the engine compartment. Just aft of the reservoir neck an in-line connector joins the hose to the engine compartment hose. The engine compartment hose travels the top left front fender wheel house to the dash panel, passing through a grommet into the passenger compartment. In the passenger compartment, another connector joins the engine compartment hose, and then up through the front driver pillar to the headliner, then above the headliner along the left roof to the rear of the vehicle. It comes out above the lift gate, in the hinge gap, and into the lift gate to the nozzle.

Not likely to be stopped up. First find out if the pump is running, and that there's fluid in the reservoir. Look for fluid running out somewhere near the reservoir. The pump isn't running, or the hose is disconnected around the tank. Look for leaks (when running the pump, and reservoir filled) at the lift gate hinge joint.