1981 chevy c10 250 inline 6 vacuum line problem

very very old post
ok i figured your old post out.
you posted a 1981 SJ jeep to jeep grand cherokee section.
this is the early Cherokee and is not grand. 1995+
with no engine stated, wow)
ill not try to guess the engine.
here they are...
258 cu in (4.2 L) AMC I6
360 cu in (5.9 L) AMC V8 2-barrel
360 cu in (5.9 L) AMC V8 4-barrel
401 cu in (6.6 L) AMC V8 4-barrel

made in USA or Australia, ill guess USA

the vacuum setups vary by carb used
and if FED usa or Calif USA setups
fed was called 49 state back when...
and there is the high altitude versions.
and std or HD cooling versions (huge list of vacuum setups, if you want look in alldata.com and behold.
omg one more the Canada version.... (ill skip export versions)
calif versions are huge complex....

so ill guess the 360 2 barrel,

There is only 4 vacuum lines on that engine

1- brake booster line

2- purge line to purge solenoid (top center of throttle body)

3- PCV hose. run straight from PCV to side of intake at base of throttle body

4- fuel pressure regulator line (short small diameter hose runs from #6 intake runner to fuel pressure regulator

5- tube that connects front cam cover to rear cam cover to improve vapor venting

http://www.hyundai-forums.com/attachments/gk-tiburon-coupe-s111-2003-2008/38204d1276396353-vacuum-lines-2004-tiberon-pict0001.jpg

Here is the firing order for the 4.9 liter in-line six cylinder engine.

The F100 ended in 1983, so there is some confusion on your 1987 Ford F100. The F150 started in 1983 and was available in 1987, but not the F100. You have this listed under the 1981 Ford F100 category.
The 300 CID = 4.9L In-Line (Straight) 6-Cylinder.
In order to best answer your question I have included both the 1981 F100 4.9L and 1987 F150 4.9L below. The only difference is with the Distributor Cap Configuration and Connections.

For the 1981 F100 300cid=4.9L:
Firing order:
1-5-3-6-2-4
Cylinders:
(back)
...6
...5
...4
...3
...2
...1
(front)
Distributor:
...(back)
.........4..[.]-clip
2
...................1
6
................5
[.]....3

For the 1987 F150 300cid=4.9L:
Firing Order:
1-5-3-6-2-4
Cylinders:
(back)
..6
..5
..4
..3
..2
..1
(front)
Distributor:
.......(back)
.................4
.....2
[.]
.......................1
..6
.........................[.]-clip
....................5
.......3
.........(front)

Let me know if this helped, or if you have additional information or questions. Feel Free to contact me at FixYa.com!

Use a industrial vacume tester, check each port coming off of the manifold, run your lines.

For the 1993 Chevy Lumina:
I do not know if you have the 2.2L In-Line 4 Cylinder, 3.1L V6, or 3.4L DOHC V6 Engine; however I have included all below.

For the 2.2L (4-Cylinder)
Firing Order:
1-3-4-2
Cylinders:
......(back)
1.....2.....3.....4
......(front)
Ignition Coil Connections:
o <---4
...o <---1
.........
......o <----3
.........o <----2

For the 3.1L V6:
Cylinders:
...(back)
5.............6
3.............4
1.............2
....(front)
Ignition Coil Connections:
.|.1..4.|..|.6..3.|..|.2..5.|


For the 3.4L DOHC V6:
Firing Order:
1-2-3-4-5-6
Cylinders:
.......(back)
1........3.........5
2........4.........6
.......(front)
Ignition Coil Connections:
.|.1..4.|..|.3..6.|..|.2..5.|

Let me know if this helped, or if you have additional information or questions. Feel Free to contact me at FixYa.com!

Any time your dealing with a 4x4 system the best start is at you front axle. Its primarily a vacuum leak so check to see if the 2 vac lines are hooked up (its good to check the electric connections.). When your 4 wheel drive is engaged and the motors running you should have vacuum at one or both of thee lines depending on if your in 4 hi or low .
If no vacuum at axle check the Vacum switchs(the plug with 4 vac lines) on top of the transfer case it will have 2 feed lines(grey & green) they conect in to the into the vacum harness on back of motor (passanger side). A vacum schematic is normally located on the raditor core support (right under the hood next to hood release)
Hope this helps

1. Well it can happen to the best of us check your firing order again it's actualy pretty simple.

1 3 5
2 4 6 This is how the firing order is 1 3 5 being in the back of the engine towards the fire wall and 2 4 6 in the front. Just place the wires on the corresponding numbers.

that vacume line goes back to the transfer case, the end that goes behind the motor hooks to a steel tube so it does not get hot from the exhaust., my guess it should be hooked up so it will feed vacume to the vacume ball so it can lock in the axels. if you start the car and shift into 4 wheel drive and listen under hood you should hear a hissing sound, that is vacume, if you can't hear it there, you may have to craw under the right side to hear it, probably came unhooked underneith the car

There is a vacum powered actuator on the front differential housing on the passenger side. It gets it's vacum from two valves mounted on the firewall just behind the battery(to left). The white line feeds manifold vacum to the valves. Check for vacum at white line with engine running. If no vacum there is a break in line from manifold. If vacum check the pink and blue lines by applying vacum to each one. The vacum should hold. If not check lines from valves to vacum actuator. Most likely it will be the actuator. If both lines hold vacum check valves. Remove electrical connectors from both valves. Connect a wire from one of the terminals of the valve to ground. Touch a wire from the battery + to the other terminal of the valve. Listen for a clicking sound. If no sound valve is bad. Replace valves(s). If this doesn't lead you to the trouble it's probably a mechanical problem inside the differential. However most likely there would other noises.