96 tacoma 4wd not working after engine swap

Hey guys, so I recently swapped a lower mileage 3rz into my 96 4wd. It went well, no issues really. Pulled the engine from another 96 4wd. I've run into an odd issue. My 4wd won't work. It's a manual transfer case, but NO manual hubs. The 4wd worked perfect before I swapped engines.The donor pickup DID have manual hubs.

I checked the fuse, its fine. I don't think I missed a harness plug. I did clean a lot of electrical plugs with the crc electrical cleaner and I put a good amount of di electric grease on all plugs. Anyone ever have an issue like this? Is it because the donor pickup had the manual hubs?

 

For the waterproof harness connectors, you shouldn't put the di electric grease on the on the pin/plug interface, just a small amount to lubricate the seal between the two parts is all that's necessary. There's a good chance you put too much grease in, and one of the switches isn't reporting back correctly.

Anyway, start down the normal "4wd not working" path.

 

Thanks. I had that thought too, so I really hit the plugs hard with more electric cleaner, then some MAF cleaner because it evaporates faster. Unless I am messing about with wrong pigtail. It's the only one that goes down towards the front axle.

 

There are actually a few open threads on this at the moment. But you need to figure out what isn't working. Manual t-case rules out the t-case actuator, but not the switches that tell the 4wd controller that the transfer case is locked in. Then after that you're looking at the ADD actuator on the stub shaft.

 

Was the truck down for a significant period of time for the engine swap? Like how recently was 4wd engaged? I had a '98 4runner sit for about 9 months and in that time the 4wd actuator froze up, and the solution ended up being to hook a handheld vacuum pump up to the actuator and suck it into the engaged position. From there on out the normal vacuum pressure of the system was capable of engaging/disengaging on its own (just needed assistance to get it engaged that first time).

 

4wd was used right before the swap. It was working fine. I am thinking I need to double check vaccuum lines. I wasn't super familiar with how this system worked.