So I fabricated my own transmission line pressure booster as per the DIY here. Things run great except for the upshift from 2nd to 3rd. We're not talking about the kickdown 2nd to 3rd, just the normal 2 to 3 shift.

Any thoughts as to why only this particular shift would be so affected?

Thanks

 

And now it's gone into limp home mode and throwing codes p0700 and p0733. I even removed the sonnax wire and reset the PCM and nothing helped.

Help!

 

And to think as was >this< close to doing that myself except I couldn't get the plug off as I broke the red tab inside the plug. So I just decided to do the trans filter/fluid change and left it at that. Already feel a nice improvement while driving. Sorry to hear that, man. There maybe another way to clear the PCM?

 

The problem was probably already in the works. Just happened to fail after the Sonnax.

Might drop the pan and check the wiring as well as making sure all of the pins in the plug are all the way in and there are no broken wires.

 

I have done nothing to my tranny and i have the same problem u do. Its almost like a lag from 2nd to 3rd. I changed the tranny filter and fluid and did not see anything. If you figure out what the problem is let me know.

 

I remember I had made mine some time back and I never had any issues. I have a Sonnax now though. I made one for a guy out here at work (MegaBlackTank) and he still has it on his and no issues.

 

So, it's not the Sonnax. The wire I made did everything it was supposed to. And the tranny did everything it wasn't supposed to. 3rd and 4th gear decided it was time to retire to Florida... Just so happened that a little bit more line pressure was enough to buy them the ticket south.

So, Rob3069usmc, I hope that it's not the same issue I had because, hello new transmission.