I have the 95 3.0 L LS and since I changed out the plugs, wires and coil packs it has had no power. Once you take off the pedal is lifeless until you floor it. Intermittently I get the CEL on and it's like its on limp mode. Biggest problem I have is that it has the OBD2 Data port but won't work with any of the modern diagnostic tools. Best i could come up with was either 34 or 24 code by counting the blinks. I'm pretty sure there is a vacuum leak but cant find it and the dealer and local shops don't really want to fix it since it wont run on their computers. I really would love to change the computer to a 96 or 97 if its possible and make life much easier and work with OBD2.

I changed out the TPS, Fuel Injection Pressure Reg, MAP, MAS, IAC and cleaned the Throttle Body. About to take off the Manifold again and change all the hoses and Camshaft Sensor. Any idea's?
Also, where do you recommend buying parts from?

 

I know it sounds ridiculous but I have to ask. Have you verified the plugs are connected to the correct terminals on the coil packs? The cylinder numbers should be cast onto the intake plenum right behind the coil packs and I also uploaded a picture of the cylinder fire order just in case. Unless you have another one laying around, I would also take a look into getting a cheapo junkyard ignition control module and slap it on there to see if that resolves the issue. Although I haven't had the opportunity to work on a 95 model, I'm fairly certain the TPS has to be calibrated. I googled it and came up with this guide to calibrating the TPS for the 95 Montero w/3.0L as the 3.5 uses the more modern setup introduced in 96. There is also the remote possibility you could have a bad spark plug cable(s) that is shorting to ground or not making connection. Also probable to have a bad coil pack out of the box, try swapping them out one by one and testing to see if the issue is resolved.

Just a few ideas off the top of my head.