Overdrive Questions

[Marauder]

Anyone with a tune have any issues with overdrive? On occassion, mine doesn't want to shift into OD if the OD button was touched at all. If I leave the button alone, I'm fine. If I shut the car off and on later on, the car is fine.

[MERCMAN]

I have had that problem on occasion as well. I don't think it is the custom tune that causes it. Next time it happens, drop it into neutral hit the OD button then drop it back into drive, that should unscramble your problrm :up:

[gpfarrell]

My overdrive is much happier now than when it was "untuned".

[Marauder]

I have had that problem on occasion as well. I don't think it is the custom tune that causes it. Next time it happens, drop it into neutral hit the OD button then drop it back into drive, that should unscramble your problrm :up:

So clicking the button a few time in neutral clears it out?

[Bill Lalk]

Anyone with a tune have any issues with overdrive? On occassion, mine doesn't want to shift into OD if the OD button was touched at all. If I leave the button alone, I'm fine. If I shut the car off and on later on, the car is fine.
Yes sir, I have the same problem. I thought there was a problem with my new tune. I always turn off my O/D soon as I start my car. Only use it on the freeway. Well, no more. With a tune installed, I can not mess with the O/D at all or the shifting gets messed up.

[Drock96Marquis]

odd that'd you'd have an issue like that.

I assume you; like most others here, have a Lidio tune?



A tune could very well effect the TCS (Transmission Control Switch (OD lockout)) operation, as the TCS is used by the PCM. The PCM is designed (or at least is supposed to) such that if the switch is behaving erratically (ie failing), whillst the car is in gear, the o/d lockout feature is disabled, and normal operation can take place. THis is probably why Mercman discovered shifting to neutral and again depressing the TCS resets it's operation.
There is a tolerance of normal vs erratic operation, erratic is probably liek on/off/on/off within a second (ie not going to occur with even if you depress it mad-crazy like :P)
If for some reason the PCM was altered, such that this threshold of 'normal' operation is made smaller, I suppose you could have an issue similar to this.



I don't know why Lidio would even touch this parameter,
and I doubt he did/does. Perhaps it is something overlooked from SCT's out-of-the-box parameters, prior to Lidio's tweaking.

[Bill Lalk]

Yes, I do have a Lidio tune. If I drive like before(turning off O/D on start-up), 4th shift changes from 35 to 45(ish) under same pedal pressure. Some downshifts, and even some upshifts, under hard excelleration seem sluggish. I had the same problem with the DR tune. It would vary - 1 time it would downshift and take off great and even chirp the tires between 1 & 2, then the next few times it was crappy, like it had a mind of its own. If I don't ever touch the O/D on/off button, it is very consistant, although I am still not satisfied I am getting all I could from the tune. Lidio thinks it may be my car and I plan a trip to his place in MI next spring/summer.

[Marauder]

odd that'd you'd have an issue like that.

I assume you; like most others here, have a Lidio tune?



A tune could very well effect the TCS (Transmission Control Switch (OD lockout)) operation, as the TCS is used by the PCM. The PCM is designed (or at least is supposed to) such that if the switch is behaving erratically (ie failing), whillst the car is in gear, the o/d lockout feature is disabled, and normal operation can take place. THis is probably why Mercman discovered shifting to neutral and again depressing the TCS resets it's operation.
There is a tolerance of normal vs erratic operation, erratic is probably liek on/off/on/off within a second (ie not going to occur with even if you depress it mad-crazy like :P)
If for some reason the PCM was altered, such that this threshold of 'normal' operation is made smaller, I suppose you could have an issue similar to this.



I don't know why Lidio would even touch this parameter,
and I doubt he did/does. Perhaps it is something overlooked from SCT's out-of-the-box parameters, prior to Lidio's tweaking.

I don't have Lidio's tune. I tuned it myself with the SCT-1725. I wonder if it's a flaw with the line of tuners?

[ckadiddle]

I have not noticed any of this type of issues, either stock or after loading tune.

[MERCMAN]

So clicking the button a few time in neutral clears it out?

Sorry, I missed your post,,,

I usually click it two times :up:

[Power Surge]

A tune shouldn't affect the button, nor the other way around.

Can you guys describe what the car's do when this happens?

Are you saying that if you turn the O/D off, and then back on, the car won't go back into O/D?

[Marauder]

A tune shouldn't affect the button, nor the other way around.

Can you guys describe what the car's do when this happens?

Are you saying that if you turn the O/D off, and then back on, the car won't go back into O/D?

Yup....if I don't touch it, it works fine. When I press it to disengage the OD and then press it again when I need OD, it won't shift from 3rd into 4th (OD).

[MERCMAN]

Same here, it doesn't happen every time, just infrequently,,,no rhyme nor reason.