4wd not engaging

[sgull]

I'm fairly certain the four wheel drive function on my brother's 2000 Kia Sportage is not engaging. The 4wd is one of those electrically operated shift on the fly types. I watched the vehicle as it attempted to go up kind of a slippery snow covered inclined driveway and only the front wheels spinned, but not the rear wheels. In the past, with the 4wd engaged with this vehicle, it had no trouble going up the little hill with the same surface condition. The driver had turned on the 4wd and the indicator idiot light on the dash also indicated it was in 4wd.
What's likely the cause for the 4wd not to be engaging? What might be a way to troubleshoot to any extent?

[HotinOKC]

It's has to be working if the fronts are turning. This vehicle is normaly RWD.

[sgull]

Originally Posted by HotinOKC

It's has to be working if the fronts are turning. This vehicle is normaly RWD.

Correction: The fronts weren't turning but the rears were.

[HotinOKC]

Ok, that makes more sense now.

I'm guessing the hub assembly needs replacing, or there might be a damaged vacuum line going to them (the hubs).

[MMMarvis]

I have a 2002 kia sportage 2dr ( jeep?)
Best condition, lowest miles and cheapest I could find at the time.

Mileage has dropped from 25/27 to 22/24 this winter ??
But that is a different issue.

4wd Mine is a manual transfer case, but the front is vacuum operated hubs. There has been issues with the seals leaking at the hubs, improved in 2000 ? Time, age and wear will make vacuum leaks that will prevent the front from locking in.

Marvis

[sgull]

So what's the general procedure to determine whether and where specifically the vacuum leak might be occuring? Is this a DIY job or too much of a pain in the rear for the average Saturday mechanic? Do I probably need to hook up a vacuum gauge, etc? How costly of a repair is this anyway?

[MMMarvis]

Personally Buy manual locking hubs.
About 150.00 and a couple hours work and very Positive results.

[sgull]

Originally Posted by MMMarvis

Personally Buy manual locking hubs.
About 150.00 and a couple hours work and very Positive results.

Sounds like the way to go, I'll check into it further. Then I wouldn't need to worry about the vacuum leaks at the seals at all??

[badeyeben]

No you won't have to worry about the vacuum lak as long as you do NOT press the 4wd switch. You can disconnect the electric plug under the hood to insure it does not work even if you hit the switch.
I had the same problem with my 2000 Sportage. The entire wheel assembly must be vacuum tight for the system to work. No worn seals or anything. The dealer quoted me $900 to fix it. I had extended warranty so they paid to fix it. I got it home and tested it in mud and it did not work. Called the dealer and told them. They said they had not tested it but had changed everything the manual said was needed. I called the warranty company and told them the dealer had not fixed the problem. They said they would look into it. A week later the warranty company called and said they no longer would allow any warranty work from this dealer on my vehicle. I would have to use another dealer. Well the closest one was 300 mile away so I cancelled the warranty and got a reimbursement for the remainder of the warranty.
But I still had no 4WD. So I started to examine it on my own. I took the line apart from the rubber part to the steel part and found it plugged up with dirt. Really hard packed dirt. This was at both wheels. I bought plastic line for a refrigerator ice maker and hooked it up from the swith under the hood to the wheels. Took some rigging but I got it to hold vacuum and tried it out. Still did not work! I called the warranty company back and after some serious discussion with them found out the dealer had only replaced the rubber line portion of the system. 2 rubber lines valued at $30 each according to the warranty company. Long story short (well a little late for that now) they had not fixed the 4WD. I bought manual lock-outs for $150 and installed them in less than 1/2 hour. You do not even have to jack up the vehicle. I unplugged the part under the hood where the solinoid is to the vacuum hookup. It takes a little time to trace the lines from the wheel to the solinoid the first time. But you will see it when you do. As long as it does not engage it will not draw vacuum from the vehicle. But I suspect the lines are plugged anyhow so it can't draw air.
You have to get out and lock the hubs by hand but at least it works when you need it.

[sgull]

Originally Posted by badeyeben

No you won't have to worry about the vacuum lak as long as you do NOT press the 4wd switch. You can disconnect the electric plug under the hood to insure it does not work even if you hit the switch.
I had the same problem with my 2000 Sportage. The entire wheel assembly must be vacuum tight for the system to work. No worn seals or anything. The dealer quoted me $900 to fix it. I had extended warranty so they paid to fix it. I got it home and tested it in mud and it did not work. Called the dealer and told them. They said they had not tested it but had changed everything the manual said was needed. I called the warranty company and told them the dealer had not fixed the problem. They said they would look into it. A week later the warranty company called and said they no longer would allow any warranty work from this dealer on my vehicle. I would have to use another dealer. Well the closest one was 300 mile away so I cancelled the warranty and got a reimbursement for the remainder of the warranty.
But I still had no 4WD. So I started to examine it on my own. I took the line apart from the rubber part to the steel part and found it plugged up with dirt. Really hard packed dirt. This was at both wheels. I bought plastic line for a refrigerator ice maker and hooked it up from the swith under the hood to the wheels. Took some rigging but I got it to hold vacuum and tried it out. Still did not work! I called the warranty company back and after some serious discussion with them found out the dealer had only replaced the rubber line portion of the system. 2 rubber lines valued at $30 each according to the warranty company. Long story short (well a little late for that now) they had not fixed the 4WD. I bought manual lock-outs for $150 and installed them in less than 1/2 hour. You do not even have to jack up the vehicle. I unplugged the part under the hood where the solinoid is to the vacuum hookup. It takes a little time to trace the lines from the wheel to the solinoid the first time. But you will see it when you do. As long as it does not engage it will not draw vacuum from the vehicle. But I suspect the lines are plugged anyhow so it can't draw air.
You have to get out and lock the hubs by hand but at least it works when you need it.

Great info! Sorry to hear you had all that trouble, sounds like a nightmare. Thanks though for the heads up and the advice!

[sgull]

So tell me, Badeyeben, from where can I purchase these manual lockouts (what do I ask for?) and what generally is involved for installation? thanks...