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Old 09-20-2005, 06:36 PM   #1
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Default Trans shifting question

Simple question. Besides the ECM( I think) what else would control the shifting into OD on my 90 SSE? Reason I am asking is that it seems that since the engine blew, you have to drive faster before it will engage into OD. It used to engage at about 80km/h (50mph), and now you have to get close to 90km/h ( 55mph).

Also one thing that I wondered about since we got the car is that once it is on OD and you go up a slight hill, you press on the gas more and the rpms drop more and the car still increases in speed, but if you let off pressure just a bit, the rpms jump back up. Which is why I always thought it was line pressure or lack there of.

Could these be related?? Also is there anyway to adjust when the OD kicks in??
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Old 09-20-2005, 07:48 PM   #2
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Default Re: Trans shifting question

Quote:
Originally Posted by sse1990
Simple question. Besides the ECM( I think) what else would control the shifting into OD on my 90 SSE? Reason I am asking is that it seems that since the engine blew, you have to drive faster before it will engage into OD. It used to engage at about 80km/h (50mph), and now you have to get close to 90km/h ( 55mph).

Also one thing that I wondered about since we got the car is that once it is on OD and you go up a slight hill, you press on the gas more and the rpms drop more and the car still increases in speed, but if you let off pressure just a bit, the rpms jump back up. Which is why I always thought it was line pressure or lack there of.

Could these be related?? Also is there anyway to adjust when the OD kicks in??
You are looking at 2 diffrent situations...

Ok, for the OD and the RPM'* dropping, that is the TCC coming in and out of play... It depends on the speed and the amount of engine load, that the ECM will lock and unlock the TCC.. If you let off the gas and reapply your foot, the TCC will then be unlocked, when the speed and load are right again the TCC will lock up again.. And sometimes it will lock with your foot on it a bit... You'll see the RPM'* drop like a rock, most likely feel it a bit too...

For the second it sounds like you need to adjust the Throttle Valve cable or TV cable... If the adjuster is out one notch too far it can cause all of the shifts to be delayed say 5-10 MPH.... Or KPH.... Have you noticed some slightly higher shift points?

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Old 09-20-2005, 08:55 PM   #3
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Maybe your higher TCC lockup speeds are due to a different final drive ratio? You have the same final drive ratio on the new trans? Or did you use the ECU from the donar?

I'm just assuming you did a swap due to your sig..
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Old 09-20-2005, 08:57 PM   #4
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I don't think he made any changes to the ECM or trans...

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Old 09-20-2005, 11:31 PM   #5
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No i think he just changed the engine. Your TV cable must have got knocked out a notch or two and that could do it. As for the RPM'* that'* just your TC unlocking and locking under varying load conditions. But going into OD at 55 is ok too. Mine goes in about 47-52 depending on the load so you're pretty close
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Old 09-21-2005, 01:46 AM   #6
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Come to think of it I think all the shifts are a bit higher than before. I did have to disconnect both throttle cables and the TV cable to be able to remove the engine. I did also remove the TV cable from the top of the trans since it was in the way to get to one of the bolts. I will have to look into re-adjusting the TV cable.

Time to search the forum, lol.

EDIT: As for the RPMs, I should have explained it a bit better. I can be driving with the TC locked up in OD, and if there is a slight incline ( enough to step on the gas to not slow down too much), I can push on the gas just enough and the RPM'* drop further than they usually do in OD, so there is a higher load on the tranny. That is why I figured maybe the line pressure had something to do with it, and that the car should have always gone that low when it goes into OD.
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