4R70W weak first gear, no 4th gear?

BlackVert

15 Year Member
Oct 3, 2003
5,589
9
98
Bethesda, MD
I have a 410ci mated to a 4R70W with a Street Edge convertor, 3000 stall. I just got the car back from the installation of the engine and transmission, and am starting the tuning process.

I have a tune from a guy who has a 1995 GT with a 4R70W tranny and he says his transmission is strong and shifts great. I took his tune and entered my displacement and injectors and stuff.

I have 3 issues I need advice on ...

(1) Starting from a dead stop is extremely slow. it seems like the transmission is just barely engaging until somehere near 10 MPH, and then the rpms jump and is shifts into 2nd, at which point it is much more normal.

(2) The speedometer is way off. I can be going about 60 on the highway and my speedo thinks I am going 85.

(3) It seems to not shift into 4th gear. Again, on the highway going about 60, the RPMs are at 3000, which seems way off for 4th gear with 3.73s. It should be closer to 2000 RPM, not 3000 RPM.

I ran a datalog today on my way to work, with the Torque Convertor Lockup State in the payload. Probably about 95% of the time, it was 0 (zero). That doesn't seem right to me.

Any thoughts? Could it be the tune? How can I troubleshoot?
 
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Was your car a stick car before this? Don's site mentions needing an additional box to enable/disable the overdrive in addition to having an automatic-enabled EEC.

Wes
Yes, it was a stick before. Apparently there is another controller that goes back behind the glove compartment to control the tranny. Scott (the installer) got one from PrestigeMustang and installed it.

When I press the "Overdrive disable" button, the light in the dash comes on to indicate that the overdrive is disabled. Of course that only means that that part seems to be hooked up right, which may or may not mean that the other stuff is right ...
 
i have both good and bad news ...

the good news: the transmission is fine

the bad news: the computer and/or tranny controller must be wired wrong

the tranny guy said that when you take your foot off the brake, it commands 2nd and when you give it gas, it commands 4th

i almost wish the transmission was bad because at least that is a known quantity that the transmission guy could fix. now i have to find someone who can trace the wires and make sure it is all wired correctly.

this may not cost as much, but it will probably be more painful

ugh
 
i have both good and bad news ...

the good news: the transmission is fine

the bad news: the computer and/or tranny controller must be wired wrong

the tranny guy said that when you take your foot off the brake, it commands 2nd and when you give it gas, it commands 4th

i almost wish the transmission was bad because at least that is a known quantity that the transmission guy could fix. now i have to find someone who can trace the wires and make sure it is all wired correctly.

this may not cost as much, but it will probably be more painful

ugh

Were any of your harnesses spliced to make the automatic happen?

Here's a start: http://fordfuelinjection.com/files/Trans_harness.gif

Wes