FMX starting off in 2nd most of the time. Got any ideas?

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Joined
Jan 17, 2015
Messages
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Location
California
My Car
71' Grande project.
I have about 200 miles on the car since I got it "road worthy"

The FMX in it was rebuilt with some secret sauce from Jay at Broader Performance (I got an email into him for ideas too).  

I can't quite figure it out.  For every time it starts in 1st gear there will be 3 times it starts in 2nd gear.  It is driving me nuts.  Fluid looks and smells like new.  Just checking in on the forum to see if anyone has previous experience.

 
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Hum........if we looked at the obvious first? then the shifting adjustment rod needs adjusted. If that doesn't help to cure it?  then go deeper into the tranny. I wouldnt think it would be the shifting module? however check the color stripe on it..

If he secret sauced it :) who knows?. But a common thing to do, to make it shift faster and harder on the fmx is to leave out the ball check on the 2nd gear. 

Lets see what your fella says he did first.  

 
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Tells it when to shift. It looks like a silver air pod and will have a paint mark on it with a certain color.

 
I’m about 90% sure the modulator is a blue stripe.  Can confirm on Friday.
Might try these ideas?

I believe I would try to adjust the modulator screw 1/2 turn at a time to see if you affect the shift. Its a easier thing to try than pulling the tail piece to check the governor. 

Was the modulator new or used? correct color stripe? also check to see if you have a good vacuum at the hose, NO pinholes in the hose. The hose is soft and supple no cracks.  

 
Modulator is “new” (less than 3 years). All the vac lines are less than 2 years old.  As best as I can tell only a blue stripe modulator is readily available- but I could swear it may have had a green one in the past.

 
Solved.

I made a miniscule adjustment to the shift linkage - no change- still had intermittent first gear in D.

I took apart the governor and checked it.  Seemed squeaky clean- but I did hit the bore with a Superior bench buddy brush (brush with mild abrasive for valve bodies).  Put it back together - same issue - intermittent first gear.

Then I decided to get serious and take a transmission fluid bath.  I dropped the pan and valve bodies in order to check out the 2-1 scheduling valve.  it was a little sticky so I cleaned up the bore with a bench buddy brush.  I then proceeded to launch the lavender colored 2-1 scheduling valve spring into low earth orbit.  I did not hear it land.   Looked around for a while with no luck finding it.  I had a Transgo 37-1 kit sitting in the garage that had a new 2-1 scheduling valve spring in it- so in went the Transgo kit in its entirety.  I pulled everything apart in the valve bodies and checked for free movement.  Hit up a few with the bench buddy brushes and a little ultrafine scotchbrite.    Put it all back together and took it for a drive.  It drives as it should- I now start in first every single time.  Now to figure out how to make the 2-3 shift a little later.  At WOT it shifts 2-3 at 5,000 RPM.

I'm curious how it would have done without the shift kit.  If I ever find the original spring and feel like another transmission fluid bath maybe I will find out.  Initial impression is that the Transgo kit is still very street friendly without any bang shifts, however 2-3 light throttle is more noticeable than before.

 
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Nice, always good to solve a problem, even when the solution isn't clear. My guess is that the original spring would have worked, too. 

Yeah, there is not any way to pull a valve body, with the transmission in the car, without the shower. I've tried everything to stay clean, except those shoulder length examination gloves that veterinarians use when pregnancy checking a cow.

 
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