I always get these two codes together,anyone have any idea why?

 

First one is leak in evap system; 2nd is trans shift solenoid. Can't see how they could be related..?

 

This always happens on a very humid or rainy day.

 

P0755 indicates a circuit malfunction. Since you say it always happens on a rainy day, chances are that you have either: exposed wire (blame Swedish rats/mice)

or

An open circuit between Solenoids --> TCM or TCM --> Ground

Get a wiring diagram, a DVOM and a couple cases of beer. Test EVERY connection of the TCM specially the ground. If you still can't find the culprit, take apart the intake and check that the ground points under there.

Specially check the ground point near the knock 2 sensor, this one seems to be a preferred chewing wire for rodents.

Solenoid #2 should have 12~15 Ohms, if too far out of spec, you might need to crack open the transmission solenoid cap and replace it. It's a small time-consuming challenge.

PM me if you need a solenoid.

 

tested no. 2 soleniod at the transaxle connector terminal 22 getting 3000 ohms,I get the same reading at TCM connector pins 20&28.any way it could be a ground piont under the intake?

 

I just got your PM.

I belive the TCM is grounded next to knock sensor #2. Poor ground will cause the TCM to send too little voltage to the solenoids.

I would check all ground wires in the engine compartment. There is a site floating around the net with detailed diagrams of the electrical system.

I really hope grounding is the issue. The other problem point might be corroded contacts at the trans connector. However this is unlikely.

If grounds check out, crack open the trans solenoid access cover and take out each solenoid. Test them individually, and test all of them.

Let me know if indeed solenoid 2 is our of spec.

 

cleaned up the two grounds under the intake one from neg batt cable and one off wiring harness,also cleaned the body ground from neg cable.Ohms are down to 81 ohms now :-))) on pin 22 of trans connector .I read there may be another ground under the right head light,will clean that up and the two at the back of the motor.Any others you can think of I should check?Still need to check a few other things like check for corrosion under the TCM conecter.Once I have checked everything else then I will worry about cracking open the trans.This trouble started after I had a leak in the turbo cooling inlet hose so it may still be a bad ground.Add that the ohms read got better after cleaning the three grounds I have maybe I can avoid cracking the trans cover.

 

Oh wanted to add at least my intake and Throttle body are now clean