[kevinocall]

Situation: 1999 RR 4.0 Gems with 190k miles.
I recently did new head gaskets (myself!) and all went well. But, since then, the transmission does not want to shift down to a lower gear when I want to accelerate. Obviously something I did, or forgot to do. But what?

Can anyone tell me: is this function mechanical, electronic, vacuum-assisted, or what? Once I know this, I should be able to trace back to the problem. Thanks for the help in advance,

Kevin in Minneapolis
[email protected]

 

[kevinocall]

WHy no answers? SImple question...

Should be an easy one. Is everyone away on summer holiday or what?

 

[disco biscuit]

How do you mean once you find this out you can start tracking it down....Does it have a cable coming out of the tranny, its usually above the pan gasket lip. Does it have a vac line running to the same pan gasket lip maybe at the back...should have a modulator valve if so. Is there a lot of electric connectors at the tranny...like a whole harness...not just a lock up wire.

I'm unfamiliar with the particular vehicle...so sounds like you forgot to hook the kick down cable up at the throttle body. That's all I got.

 

[kevinocall]

Still need more info - trans downshift problem

Thanks for taking a shot, but I'm sure someone out there knows how the Kickdown function works and can just tell me to save time. Thanks, KO.

 

[disco biscuit]

Ok. You could a just looked at it by now and had it fixed but right on. You don't know if you unhooked a kick down cable off the top of the motor?... just tryina help. Sometimes its hard to get a reply here if people like me own something different...was just trying to help you figure it out rather than have you stand here complaining no one can help figure out what "should be an easy one". If you did all the work yourself and are having trouble with something you did or didnt do. How do we know what you did is the point. Good luck somebody'll be along sooner or later.

 

[kevinocall]

MIsunderstood ...

I apologize for not being clearer. I know someone here can tell me what it is on a '99 P38 that makes the transmission shift down when I depress the pedal to accelerate. There are 2 cables going to the intake, I've tried randomly loosening / tightening each and both, no result. There is a vacuum tube from the intake right next to where the throttle cable reaches the intake, and it goes to a round black cylinder thingy - can't see how this relates to shifting. Wires - can't see any electrical anything near the throttle or intake. So? If someone can just tell me what controls downshifting, I can solve it. Is this super-secret restricted information? CIA? NSA? Whistleblower fears? Range Rover owners are a strange crowd.
@dokdoc.com
Minneapolis.
Other news: I put in the front of the axle tie rod last week, just picked up the behind-the-axle tie rod today (called track rod), putting it in tomorrow. With the new (used) tires, I should be in great shape!
Also: this summer I took out the headliner which was sagging and put in a new one. Hardest part - finding fabric the is more than the standard 54 inches. RR's require 56 inches minimum. 10 trips to Jo-Ann fabrics, but finally found it!
Also: Hurricane wheels are beautiful but damnably difficult to clean.
Thanks for listening. :wave:

 

[RoverGuy7]

GEMS P38 is an electronic controlled transmission, unlike the D1. Kick down is controlled by ECM inputs to the TCM. It is based off of throttle position, road speed, and engine load (which is based off of Mass air flow and injector pulse)

The reason no one has really responded is there is not a very common issue with this, and more diagnosis needs to be preformed before anyone is of any help to you, unless you want to start changing parts that may or may not be bad.

With it happening right after a major repair, I would be looking for any large vacuum leaks that would throw off your MAFS reading.

 

[kevinocall]

Thanks RoverGuy, now I know where to look.

Much appreciated. I'll check and see what I can find.
Kevin in Minneapolis.