How to diagnose a vacuum leak without a vacuum leak diagnostic tool.
My ESOF won't engage, AC/heat blowers default to defrost - classic symptoms. And while we can leave without AC/heat, we really need the ability to engage 4x4 low, especially as we get higher into the Andes and the roads become rough.
I am thinking on installing a shutoff in the vacuum line that supplies the hubs so I can use 4LO for backing uphill with a trailer without having the hubs engage. Its either that or a switch to disable the PVH solenoid.
View 12 RepliesIn the past, I've had the common issues of vacuum leaks causing issues as evident from the defrost/ac and then finding busted vacuum lines. Changed out and everything fine for a few years. Now, i dont have 4wd but i dont have the tell tale vacuum leak signs. Also, even if i manually engage the hubs, still no 4wd.
I try to listen for the transfer case to engage when i switch from 2wd to 4wd, I think I hear it engaging, but to be honest the 7.3 makes so much racket Im not positive that Im hearing it, or at least not hearing it the way I "think" that i heard it in the past. I seem to recall a distinctive clunk when engaging, now its barely audible if at all. Now when I switch to 4-Low, there is the distinctive sound, and it does goes into low drive, just that its only 2wd-low, still no front wheel action.
I have never had any issues before other than the vacuum leaks, have never had reason to dig into the transfer case for any reason. The only time it has ever been touched was last summer when i had the BTS installed and all they did was remove and replace.
Do I finally need to either rebuild or replace my hubs? Is it possible not to have 4wd even with hubs manually engaged? Or is there an issue with the t-case? Or is there something else going on? I have access to a lift to attempt "driving" while all wheels off the ground, its just not mine and its a tight fit and a pain to get my truck on it.
I noticed that my 4WD is only working now when I manually lock the hubs in (they have that options!), and the air blows out the defroster when I shift, so it looks like I have a vacuum leak. Where are the typical leak points on a 2006 F250? What's the best way to confirm a leak (other than just replacing all of the hose)?
View 2 RepliesI have 2 issues and wonder if they are related. I don't have a CEL but I'm getting a P0442 DTC with my code reader - EVAP system leak detected
Also, my ESOF doesn't work. The hubs will lock manually. Can this be related?
I've already cleared the code and it came back. My ESOF hasn't been working for a while but I just haven't had the time or motivation to look into it until now.
I tried the HVAC Test and there may be a slow leak in the system. I can get the vents to switch from defrost to face vents but it switches halfway back to defrost, both are on at the same time for 20 seconds, then it recovers and goes back to the face vents.
My 4wd relays seem to work as well.
My ESOF crapped the bed as the truck was stuck in 4 Low. I took the transfer case motor switch off to access the gear underneath it.
I'm able to get vise-grips on it but it only turns clockwise. It keeps turning to a point it won't turn anymore and, if I let go, it will switch back to its original position.
I can do without 4WD until I get ESOF fixed, but is there a trick to manually changing it to 2WD?
I have my vacuum system back up and working and using my vacuum pump I determined my lines are all good. They hold a vacuum fine, but my ESOF isn't engaging my hubs. I guess that leaves either the selector on the dash or the seal at the hubs.
If it is the selector, I should just be able to just disconnect the vacuum line at the selector and use my pump to engage my hubs. How much it is supposed to take to activate the hubs?
I am having some issues with my 2003 f250 6.0l 4x4. I cannot get the 4x4 to engage. There are no lights on the dash and no power to the switch other than the light. It doesn't matter if I have the hubs in lock or auto. It just seems like i have no power to the system. I have check all the fuses and they all check fine. I also check the transfer case motor and it seemed fine. I must be missing something. This truck is worthless without 4x4.
View 14 RepliesHow to diagnose a vacuum leak without a vacuum leak diagnostic tool.
My ESOF won't engage, AC/heat blowers default to defrost - classic symptoms. And while we can leave without AC/heat, we really need the ability to engage 4x4 low, especially as we get higher into the Andes and the roads unsmooth.
I was hearing a clicking noise on my passenger front wheel when rotating by hand.
Paul suggested I remove the ESOF hub and see if it is the wheel hub or the ESOF hub. It's the ESOF hub.
So I'd like to rebuild it for sure, it also has a nicked o-ring, so that accounts for part of the vacuum leak
I'd like to service the driver's side, too, while I'm at it. It doesn't exhibit any issues, so just regular maintenance stuff there.
Parts lists?
As always, I'll take pics in return
My shift indicator switch on the trans seized up, so a local trans shop replaced it for me. Now I get no low range when I select it. I understand it needs to see the truck in neutral to do this, is there a simple adjustment? The trans shop is a long way away.
View 2 RepliesTruck has been neglected for a while so this upgrade/repair I installed Powerstop brake rotor, caliper, bracket and pads. New Timkin wheel bearing, Moog U-Joints, and new inner/outer axle seals. Also replaced all the brake hoses and the remaining original rusty brake lines. About a month before I replaced the failed Auto/Manual vacuum operated locking hubs with Mile Marker units, which do not need the vacuum line, the drivers side was missing. and was letting water into the wheel bearing. So I decided to plug them and remove the vacuum lines from under the hood as well.
If there is interest I can get pictures of the vacuum lines, and what I changed under the hood. That was pretty self explanatory.
Could not find a google search for the thread size of the vacuum nipple in the knuckle. It is a 3/8"-24 fine thread.
[URL]
Time to replace the aging vacuum lines to the 4wd and probably anywhere I can find the old rubber stuff.
What is the size of the lines and are they mostly the same?
I'd like to order a roll so I can make ones like the front hubs longer, stuff like that.
My vacuum pump I noticed is running constantly and also my vents are stuck on defrost.
I narrowed it down by taking off the lines going from the tank to the 4x4 solenoid and the tank to the HVAC line. If I plug both lines I get pressure to both but it still won't shut the pump off. Why won't the pump shut off? Leaky tank?
If I plug the red line back into the solenoid I cannot get pressure to come out of the HVAC line. (Switch in cab set in 2wd)
I can make the pump shut off by plugging the main inlet to the pump.
I took the tank out and can't find any cracks or leaks. Could something inside the tank be broke?
Also why can't I get pressure when the red line is plugged into the selinoid?
I can't figure it out. Almost seems like the 4x4 solenoid and the tank are both the problem.
I am in the process of rebuilding my front end and have found that the nipples that screw into the top of the knuckles for the ESOF system are rusted and need replacing. I'd like to keep the system as close to original as possible, but have had no luck in finding a replacement. What the appropriate Ford part number is or where I could pick up a suitable replacement. This would be for a 2001 F-250 4X4 with the V10.
View 2 RepliesI am in the process of replacing the complete front end on my 02 CC 4x4. Im replacing the hubs the lockers all seals and spindle axles. complete brakes with power stop and stainless brake lines ......I am going to switch back to the original automatic lockers. I am curious if has a simplified one line for the vacuum routing from the pump to the hubs?
View 7 RepliesI think my pcm has gone bad. My wait to start light won't come on an when I turn my key on I can't hear my fuel pump cut on anymore. My vacuum pump is also making a loud noise.
View 10 RepliesMy 16 year old F250 4X4 diesel has developed a problem with no backup lights working, and the vacuum pump is not getting power. The fuse (#28) checks out OK, and I'm told to check for a broken wire on or near the backup switch. I don't know where to locate the backup switch. I have the huge Ford Service manuals, but they are written with the perspective that you should already know where the switches are. Where to find the switch?
View 4 RepliesHave to get rpm's over 2k before trans will engage, then in between shifts I either have to let off throttle or let engine rev over 2k to get trans to shift...
View 3 RepliesI found out by accident that my vacuum pump is now running all the time. It's not the gray line to the heater valve and it's not the vacuum canister as I already checked the easy stuff. I need some direction where to start looking under the dash as I have never been under that part of my truck. Any common issues or where to look?
More information: The pump only runs all the time when the HVAC control is set to OFF or MAX AC.
Haven't found any other useful info on this, but local dealer says that's where my truck is leaking oil from, and since it's considered brakes not powertrain the repair won't be covered under warranty ...
Backstory goes : dropped my truck off at local dealer Thursday to repair an oil leak from near front main seal area of the engine discovered while inspecting to initiate a bumper-to-bumper warranty through Ford ESP- their platinum warranty. I figured with all the electronic widgets and non-powertrain stuffs on this beast I wouldn't mind paying for 3yrs/36k miles of trouble-free motoring, y'know?
Apparently it's the O-ring on the brake vacuum pump that's allowing engine oil to leak. I can't even find this thing, just looking for some further explanation. I'm keeping an open mind so far, I don't suspect the dealer's just trying to get one over on me, just trying to be good and educated before I go plunk down for the repair.