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So i am in Louisville, Ky. I drove here through the mountains of MD and WV. The reson i like the 2.5L DOHC is that if you keep the engine over 3,000 RPM it will just scoot up a mountain at 75.

 

With the cruise control, it insists upon downshifting to 2nd gear and holding it past the peak of the mountain. My gas mileage was an a bysmal 19 mpg. If i disconnect the cruise while climbing, the car upshifts to 4th with the torque converter unlocked and just wants to run right up the mountain. With manual speed control, i got 24 mpg at 75-85 mph.

 

In another thread someone said that there is a wire from the cruise control to the TCU. It seems that this is a signal to the TCU to use a more agressive shift pattern.

 

If it ever warms up here (and as much as i hate doing elective surgery 700 miles from home), i am willing to disconnect this wire (think of it as a labotamy for the cruise control) to see if this erradicates this god awful

behavior. Can someone (yes porc you too) find out where this wire is, and the best place to disconnect it?

 

nipper

 

PS, this is the first high speed drive in the mountains with the lift kit and the GR2's, and i had no qualms with taking the car up to 100 mph. It felt a little odd in the left twisties, but fine on the right ones. Blu was a bit of a handful at 70 with a 40 mph crosswind.

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Well I'm glad its not just me hatin' the cruise control!!

 

I've had my graspic DS2s up to about 115, they feel a little loosey-goosey on the turn-in and then settle pretty much OK.

 

 

Dave

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Which leads to the next question, where is the module?

 

 

Oh joy, i get to drive home in snow too

 

 

grrrrr

 

 

i hate feb road trips, just was missing the other half too much. i should know better, damn valentines day.

 

nipper

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hehe valentine's day in smilies: love1.gif:banghead:love1.gif:banghead:love1.gif:banghead:

 

Hm....good question, where is the module....(again this is for '96 legacy) Sorry the wiring one is so big but I didn't want to downsize it as there is so much detail.

cruise-parts-locations-96.gif

cruise-control-schematic-96d.gif

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Come on nipper, the easiest way to solve your problem is to not use the cruise control at all, and get a monkey to control the throttle for you! :banana:

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Come on nipper, the easiest way to solve your problem is to not use the cruise control at all, and get a monkey to control the throttle for you! :banana:

 

So your volunteering to be my throttle control?

 

 

heheheh

 

nipper

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With the cruise control, it insists upon downshifting to 2nd gear and holding it past the peak of the mountain. My gas mileage was an a bysmal 19 mpg. If i disconnect the cruise while climbing, the car upshifts to 4th with the torque converter unlocked and just wants to run right up the mountain. With manual speed control, i got 24 mpg at 75-85 mph.

 

Downshifting to 2nd??? I Think you mean 3rd w/o lockup. 2nd gear at 75 mph would be like 8000 rpm.

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Porcupine - great pictures boss, those are helpful. I have a cc issue with a 96 Legacy LSi and only have 95 Legacy and 97 Impreza FSM's which are different than what you posted.

 

For the purpose of this discussion I did an EJ25 to EJ22 swap and don't know where to connect the vacuum hose for the pump to. I connected it straight to vacuum and it just makes the car rev to 6,000 RPM.

 

So there must be something to "control" this vacuum? I don't see it on the FSM pic's and don't understand how CC works.

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the cruise vac line is full engine vacuum on everything I've worked on. the system modulates the vac to wheel speed in the vacuum operated throttle positioner (or at least it does in the 'Murcan units I'm used to working with - Ford/Dodge)

 

If you are just revving, it sounds like the control unit isn't getting a signal and is trying to make the engine catch up to a phantom speed input. Either that or the control unit isn't a match for the electronics

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the cruise vac line is full engine vacuum
okay interesting, that is how my 97 impreza appeared. so i'm not sure why it raced up at "idle" when i had it hooked up to full vacuum. everything else is running and working perfectly.

 

but the original EJ25 in the car "looks" (can't tell it's not in the car anymore) like that vacuum line for the cruise came from a solenoid - not direct vacuum.

 

hmmm.....

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and the solenoid was what cut off the vac so the system isn't "on" all the time. On the old add-on system I have in another vehicle, the vac was "on" but the solenoid was in the control unit - it just shut off the vac to the bellows inside the "box"

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Stock EJ subaru cruise control uses vaccum to operate the actuator, but not engine vacuum. That soleniod thing over on the passenger side strut tower is a vacuum PUMP. It generates the vacuum to pull the actuators diaphram and control the throttle. If you hook the actuators line to the manifold, it should pull the throttle open as far as it can as the vacuum in the manifold dissapears. The cruise control vacuum lines should never hook to the manifold. They are their own sub-system.

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Shouldn't really use the cc on long hills anyway. Just glad you didn't think it was auto-pilot! ;)

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That's odd. I know with the system on 90-94 they were to keep it in the highest gear. My system goes up hills no problems and no downshift. This is with a EJ22. Why would they make it more aggressive for a car with a EJ25??

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Shouldn't really use the cc on long hills anyway. Just glad you didn't think it was auto-pilot! ;)

 

Becauuuuuuuuse?

 

Dave

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That's odd. I know with the system on 90-94 they were to keep it in the highest gear. My system goes up hills no problems and no downshift. This is with a EJ22. Why would they make it more aggressive for a car with a EJ25??

 

Because we want to go faster :)

 

nipper

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