I installed a B&M ratchet shifter on my 1991 Z28 TPI A4. I didnt reconnect the convertor lockup switch. Halfway through the installation I noticed I was supposed to buy a relay from radio shack so the next day after I finished the install I bought one. What I'm wondering is......

1. What difference does it make if I dont reconnect the wire?

2. Why does the computer need to lock it when all kinds of carbed cars dont use a computer and have lockup convertors?


Thanks

 

It's actually to send the ECM a signal that the car is in Park/Neutral. If you don't connect the relay, the ECM won't know and it's possible to lockup the TCC while in Park/Neutral. That's not a big deal, because there are some mechanical variables as well for that to happen. But the big thing is that the ECM won't know to kick up the idle when you drop into gear, and that affects the smoothness of operation. I won't always cause it to stall or drop in RPMs, but makes it easier to happen. I ran for a year without the relay without problems, but when that in combination with an ailing IAC motor and clogged IAC passages came up, the car would start to die going into gear. No problems now.

 

Does it hurt acceleration?

 

Anybody?

 

No. Leaving it off, the car thinks it's in drive, so while driving, everything's normal. It's only effects the moment of transition between a drive gear, and park/neutral.