Experimenting with bypassing the AT 4th gear prohibition when cold

[bronsin]

Originally Posted by swede

would there be any issues if you used a 2 position maintained switch instead of a momentary? This would allow me to leave the switch turned on instead of having to hold it down while driving. But at the same time it could open the possibility of forgetting to turn it off and running the car like that for months, any thoughts if this could damage anything?

No you really really dont want to do that.

If the computer sees 300 ohms from the temperature sensor, it thinks the coolant has warmed up. It allows the transmission to shift into high right after that.

But you dont want the engine running like it thinks its warmed up when it isnt. When you push the momentary button, the green Cool Engine Light goes out for a couple of seconds.

Then it comes back on after you let go the button.

What we are hoping is happening is the transmission is fooled into thinking it can go into high BUT the engine is still being carburated like its not warmed up. So you want a momentary impulse. Not a continuous one.

Also, using a block heater as I am experimenting with, the CEL goes out after .4-.6 mile (as opposed to to ~ 1 mile without it) But Im not out of the neighborhood yet so I dont need high gear.

Coming home from work in another story. There Im on the freeway after less than .5 mile.

Thats what the mod is for.

[swede]

Originally Posted by bronsin

No you really really dont want to do that.

If the computer sees 300 ohms from the temperature sensor, it thinks the coolant has warmed up. It allows the transmission to shift into high right after that.

But you dont want the engine running like it thinks its warmed up when it isnt. When you push the momentary button, the green Cool Engine Light goes out for a couple of seconds.

Then it comes back on after you let go the button.

What we are hoping is happening is the transmission is fooled into thinking it can go into high BUT the engine is still being carburated like its not warmed up. So you want a momentary impulse. Not a continuous one.

Also, using a block heater as I am experimenting with, the CEL goes out after .4-.6 mile (as opposed to to ~ 1 mile without it) But Im not out of the neighborhood yet so I dont need high gear.

Coming home from work in another story. There Im on the freeway after less than .5 mile.

Thats what the mod is for.

ahhhh ok I understand now, I had to re-read the first post again. I thought that the transmission would go back to third gear once the light came back on. I must have skipped that paragraph in CTScott's explanation.

I did order a block heater from ebay last week so i am just waiting for that to come in the mail now. Driving in third gear for so long is really annoying to me since I have only owned MT cars for the last ~10 years.

I will see how the block heater works and decide if I still want to do this mod. Like you were saying I can't plug my car in at work so I may end up doing this anyways

thanks!!