68 Mustang, C4 trans won't start in 1st. If I put the selector into drive (D) it starts in second gear. I can put the selector in 1 and it will start in 1st. It's had a fluid and filter change and the modulator has been replaced. Any ideas? Thanks.

 

Try the other drive position (or 2nd on your shifter) it may be that you have the early valve body (green dot) which works exactly like you've described.

 

Can you explain this early green dot valve body thing? Mine does this as well

 

It really isn't too technical:
The early C4 which was marketed as a "dual range" transmission, has a D1, a D2, and L position for the forward gears. In the D2 position, which is closest to the N position ( the D on later cars), the trans starts out in second gear to minimize tire spin in slick conditions. The normal forward drive setting for early cars is the D1 position (green dot) (which corresponds to the 2 position on later cars)

 

Interesting, the car came with the full center console but it's not installed, so there is no selector. I will take a look at it and test the trans out again this weekend and let you know. Thanks for the info. Here's a couple pics. I purchased it almost 9 years ago and will finally have the time this winter to put on all the parts I've collected over the years and reinstall that console.

 

I would replace the neutral safety switch. I just chaged mine out. After all, I don't see how it lasted for 46 years, anyhow.

 

Any updates or fixes to your transmission not shifting to 1st? I have a 68 with exactly the same problem.
RB