Changing from 2nd gear start to 1st

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Infinitiace1992
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Changing from 2nd gear start to 1st

Postby Infinitiace1992 » Fri Jul 02, 2021 7:00 pm

Hello again all,

Is there more involved than swapping my TCU from my 91 Q to one from a 93 Q to eliminate the second gear start feature?


Ryantzer
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Re: Changing from 2nd gear start to 1st

Postby Ryantzer » Sat Jul 03, 2021 10:27 am

From what I've read in numerous posts here in this forum, changing the TCU is all that's necessary.

Infinitiace1992
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Re: Changing from 2nd gear start to 1st

Postby Infinitiace1992 » Sat Jul 03, 2021 10:50 am

Wow. Seems too simple Guess for $30 it’s worth a try. Thanks

Infinitiace1992
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Re: Changing from 2nd gear start to 1st

Postby Infinitiace1992 » Sat Jul 03, 2021 12:42 pm

Ok wish me luck. Found one on eBay for under $30. I’m assuming it’s an easy swap?

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Q451990
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Re: Changing from 2nd gear start to 1st

Postby Q451990 » Sat Jul 03, 2021 1:52 pm

Wow, that's a great deal! What's the part number? For a 93 it should be a 31036-64U20 (or the super rare never seen one ending in 64U75).

It's an easy swap, takes about 20 minutes the first time.

Infinitiace1992
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Re: Changing from 2nd gear start to 1st

Postby Infinitiace1992 » Sat Jul 03, 2021 8:21 pm

It’s the not so rare 31036-64U20. I’m not the most mechanically inclined but it does look relatively easy. It is located on the drivers kick panel by the fuse box or the passenger side by the ECU?

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Q451990
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Re: Changing from 2nd gear start to 1st

Postby Q451990 » Sat Jul 03, 2021 10:15 pm

Driver's side by the emergency brake. The part number is important to confirm you're buying a TCU that will give you first gear start. 94-95 will also work. If you post up the part number we can be sure before you buy it, or if you've bought it - take the time to install it.

Infinitiace1992
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Re: Changing from 2nd gear start to 1st

Postby Infinitiace1992 » Sun Jul 04, 2021 5:37 am

Thanks. The exact part number is 31036-64U20 from JECS and the other number listed is A64-000P45 2Z16. I’d post a pic but I have not figured out how to do that on here still.
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24467FAA-7004-4BBD-AFB5-4C4AB5FFD7B3.png
TCU (actual part I bought)

Infinitiace1992
Posts: 148
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Car: 1991 Infiniti Q45t KHI-C Ivory Quartz w/beige interior
Location: Detroit

Re: Changing from 2nd gear start to 1st

Postby Infinitiace1992 » Sun Jul 04, 2021 5:38 am

Not sure how I did it but the pic of he new TCU is attached

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Q451990
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Re: Changing from 2nd gear start to 1st

Postby Q451990 » Sun Jul 04, 2021 8:32 am

Sorry, I didn't read your last post correctly. That's the one you want!

Infinitiace1992
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Re: Changing from 2nd gear start to 1st

Postby Infinitiace1992 » Sat Jul 10, 2021 8:34 pm

The updated TCU showed up and I installed it in a little over thirty minutes. Worked like a charm and now the car is so much more enjoyable to drive and clearly much more responsive starting off on first as all cars should. Thanks for the advice and help on here.

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BCC93QT
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Re: Changing from 2nd gear start to 1st

Postby BCC93QT » Sun Jul 11, 2021 4:06 pm

I have a tcu to swap for my 1990. But I haven't put it in. At this point I'm just leaving it as it is. I don't beat on it. And use manual shift if I'm going to lay into it. Im leaving my 90 museum worthy. My 95 meh.... anything goes. The 1st gear start TCU is a significant upgrade though. Especially along with a nico ecu

Infinitiace1992
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Re: Changing from 2nd gear start to 1st

Postby Infinitiace1992 » Sun Jul 11, 2021 6:45 pm

My advice BCC93QT is to do as I did. Install the new TCU and keep the original in case at some point you want to sell it as all original. I’ve restored my 91 to look exactly as it did when new but meantime, it’s much more enjoyable to drive with first gear start. I drive this like an old lady but it’s just overall better not having to go full throttle or run through the gated shifter to get decent acceleration.

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Re: Changing from 2nd gear start to 1st

Postby 3Q Jay » Tue Jul 13, 2021 11:31 am

Glad your 1st gear start upgrade is working out!
Infinitiace1992 wrote:
Sun Jul 11, 2021 6:45 pm
...... I drive this like an old lady......
....but are you the terror of Col-o-rado bouleevard (sorry, grew up in SoCal)---or maybe Woodward Ave?


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