clarification on 4x4 problems
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Cross-Country
Joined: Jan 2003
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From: Lafayette, La
clarification on 4x4 problems
After the last hurricane I was trying to bypass some fallen trees when I got to find out my 4 wheel drive no longer works. I did some searches and read some info on the Guzzle website and have a question.
If you have a vacuum leak does your heater assy always not work correctly? That was the first thing I checked as I was stuck in the mud and everything worked as normal. I also checked the fuse for the shift on the fly and it was good. With the key on, ignition off, I can hear the transfer case motor making noise when I turn the dash switch. Do these motors either work or don't work or can their be some middle ground there?
I am just trying to clarify my troubleshooting before I start tearing things apart.
If you have a vacuum leak does your heater assy always not work correctly? That was the first thing I checked as I was stuck in the mud and everything worked as normal. I also checked the fuse for the shift on the fly and it was good. With the key on, ignition off, I can hear the transfer case motor making noise when I turn the dash switch. Do these motors either work or don't work or can their be some middle ground there?
I am just trying to clarify my troubleshooting before I start tearing things apart.
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From: Rhode Island
Have you tried to manually lock your hubs to see if that allows the 4wd to work? If you have not then I suggest you try that because It will allow you to isolate the vacum hubs as the problem if indeed the 4wd works after that. If that has no effect then you shift motor on the T-case or the T-case itself is most likely to blame.
Thread Starter
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Cross-Country
Joined: Jan 2003
Posts: 83
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From: Lafayette, La
Good and bad news. I manually locked the hubs and the 4 wheel drive worked find. When I set them back to auto and tried to shift on the fly sure enough the A/C flow went North and the 4 wheel drive felt like it was trying. I will have to do some more research tonight of where to start troubleshooting.
Thanks,
Jason
Thanks,
Jason
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From: Rhode Island
Start by checking the rubber vacum hoses coming off the hub/spindle/unit bearing behind the front tire. It make be torn or just come off.
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There's definitely a vacuum leak downstream from the vacuum solenoid, if not the solenoid itself.
From the vacuum solenoid, which should be on the passenger-side inner fender, trace the vacuum line from it going to a "T" which then leads to both front hubs. Disconnect it there, and plug it. Then, see if the heater/defrost thing still happens. If it does, that means either that small piece of line is broken, or the vacuum solenoid itself is venting vacuum to the atmosphere.
If the heater/defroster now work correctly, trace the vacuum lines down to the hubs and see if there's any breaks in the lines. Chances are, you have a cracked hose.
After that, if you still can't find the vacuum leak, disconnect the line at one hub, and plug it - check heater/defrost. Still does it? Disconnect the other one and plug and try again. This way, you can figure out which knuckle is leaking vacuum.
There's definitely a vacuum leak downstream from the vacuum solenoid, if not the solenoid itself.
From the vacuum solenoid, which should be on the passenger-side inner fender, trace the vacuum line from it going to a "T" which then leads to both front hubs. Disconnect it there, and plug it. Then, see if the heater/defrost thing still happens. If it does, that means either that small piece of line is broken, or the vacuum solenoid itself is venting vacuum to the atmosphere.
If the heater/defroster now work correctly, trace the vacuum lines down to the hubs and see if there's any breaks in the lines. Chances are, you have a cracked hose.
After that, if you still can't find the vacuum leak, disconnect the line at one hub, and plug it - check heater/defrost. Still does it? Disconnect the other one and plug and try again. This way, you can figure out which knuckle is leaking vacuum.
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There's definitely a vacuum leak downstream from the vacuum solenoid, if not the solenoid itself.
From the vacuum solenoid, which should be on the passenger-side inner fender, trace the vacuum line from it going to a "T" which then leads to both front hubs. Disconnect it there, and plug it. Then, see if the heater/defrost thing still happens. If it does, that means either that small piece of line is broken, or the vacuum solenoid itself is venting vacuum to the atmosphere.
If the heater/defroster now work correctly, trace the vacuum lines down to the hubs and see if there's any breaks in the lines. Chances are, you have a cracked hose.
After that, if you still can't find the vacuum leak, disconnect the line at one hub, and plug it - check heater/defrost. Still does it? Disconnect the other one and plug and try again. This way, you can figure out which knuckle is leaking vacuum.
There's definitely a vacuum leak downstream from the vacuum solenoid, if not the solenoid itself.
From the vacuum solenoid, which should be on the passenger-side inner fender, trace the vacuum line from it going to a "T" which then leads to both front hubs. Disconnect it there, and plug it. Then, see if the heater/defrost thing still happens. If it does, that means either that small piece of line is broken, or the vacuum solenoid itself is venting vacuum to the atmosphere.
If the heater/defroster now work correctly, trace the vacuum lines down to the hubs and see if there's any breaks in the lines. Chances are, you have a cracked hose.
After that, if you still can't find the vacuum leak, disconnect the line at one hub, and plug it - check heater/defrost. Still does it? Disconnect the other one and plug and try again. This way, you can figure out which knuckle is leaking vacuum.
Disconnecting at the hub and using a vac. gauge plus plugging the lines to confirm which hub is how I found my leaky hub. I bought the parts to replace the inner bearing but on disassembly I found the wheel bearing was failing causing the seal to leak. I replaced the bearing, o-rings, inner seals and cleaned the hubs. Now all is back to normal. Ummm m wonder if the other side is the same way.?
Many want to blame the hubs for ESOF not working and in fact it may be a vacuum leak caused by a more serious problem. Fortunately I found the bad wheel bearing before it failed on the interstate.
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However, you are correct. Usually, it's a vacuum leak or the vacuum solenoid, or dirty/sticking hubs that need to be cleaned.
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[quote=krewat;6732924]Actually, I had one hub not latching because the latch itself (small piece of plastic with a very small piece of spring steel) broke and would no longer latch. [quote]
You are right,, there is a fragile piece of plastic and the diaphram could also fail and it is not repairable.
You are right,, there is a fragile piece of plastic and the diaphram could also fail and it is not repairable.