mhassett
04-26-2010, 03:29 PM
Hi everyone, just wanting to clear up some questions I have about limp mode. I did a J35A4 swap with an 03 TL Tiptronic transmission. For some crazy reason the car will refuse to shift from 2nd to 3rd when you are in it hard. All other upshifts/downshifts, ect are perfect. No trans codes. And I can hit 7200 with a Type S auto ecu and 6500 with Base auto Tl ecu. Just no 2nd to 3rd upshift.
I ended up building a micro controller to run the auto transmission using the tiptronic upshift and downshift switches on the shifter. This works great as far as shifting goes but upsets the ECU and causes limp mode - 5100 revlimit with Type S and 5800 with Base ECU's.
I would just like to clarify that for those of you using an auto ECU with a manual trans - has anyone found a fix for limp mode? I have read people trying wiring the shift selector and pressure switches to simulate being in 3rd gear. Has anyone actually had success with this? I tried it and had no luck.
What about the other 2 (?) Tiptronic builds on here? Are you guys having any issues with your cars not wanting to shift from 2nd to 3rd? I have read on TL forums that rapid acceleration in second gear (such as a TL in the rain) causes the computer to get upset and stay in safe mode (which happens to be 2nd gear). Maybe with the reduced weight of a J swap - 2nd gear acceleration is outside of some range defined in Hondas "grade logic".
I'm considering building another micro controller to simulate the correct ratio's of mainshaft and countershaft speeds based on engine RPM... Hoping that those signals along with wiring the car to think its in 2nd gear might just work? Any ideas?
-Thanks
I ended up building a micro controller to run the auto transmission using the tiptronic upshift and downshift switches on the shifter. This works great as far as shifting goes but upsets the ECU and causes limp mode - 5100 revlimit with Type S and 5800 with Base ECU's.
I would just like to clarify that for those of you using an auto ECU with a manual trans - has anyone found a fix for limp mode? I have read people trying wiring the shift selector and pressure switches to simulate being in 3rd gear. Has anyone actually had success with this? I tried it and had no luck.
What about the other 2 (?) Tiptronic builds on here? Are you guys having any issues with your cars not wanting to shift from 2nd to 3rd? I have read on TL forums that rapid acceleration in second gear (such as a TL in the rain) causes the computer to get upset and stay in safe mode (which happens to be 2nd gear). Maybe with the reduced weight of a J swap - 2nd gear acceleration is outside of some range defined in Hondas "grade logic".
I'm considering building another micro controller to simulate the correct ratio's of mainshaft and countershaft speeds based on engine RPM... Hoping that those signals along with wiring the car to think its in 2nd gear might just work? Any ideas?
-Thanks