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Discussion Starter #1
The automatic doesn't seem to shift when in auto, I did try starting at 1 then shifting to 2 and noticed a shift, 2 to 3 notta, nothing. What gives? modulator, vacuum??? I like using words I know nothing about!!

Could be the trailblazer to Carlisle again!!!
 

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trans. not shifting

The automatic doesn't seem to shift when in auto, I did try starting at 1 then shifting to 2 and noticed a shift, 2 to 3 notta, nothing. What gives? modulator, vacuum??? I like using words I know nothing about!!

Could be the trailblazer to Carlisle again!!!
If it will manually shift from 1 to 2 but will not shift to 3, I would look at to modulator line first (check both rubber connector hoses) for fit and leaks. If the line is ok then pull the hose off the modulator valve end and check for trans fluid if that appeals fine then try a new modulator valve. The TH180 is a pretty tough transmission and usually operates unless it has been sitting up a long time in which case sometimes you get a piston stick in the valve body.
 

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I am sure you checked the oil level. Oil pressure is very critical with automatics.
Others might have more ideas.

In case you need a new one, I just took mine out for a manual conversion. Shifts well and is available.

Dieter
 

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Discussion Starter #4
In case you need a new one, I just took mine out for a manual conversion. Shifts well and is available.
I have one that I took out of my GT that was rebuilt and never used!

The TH180 is a pretty tough transmission and usually operates unless it has been sitting up a long time in which case sometimes you get a piston stick in the valve body.
It has been sitting for a year or so I was told.

I'll double check the fluids, modulator and vacuum lines OR have the tranny place do it tomorrow!!
 

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Th180

I have one that I took out of my GT that was rebuilt and never used!



It has been sitting for a year or so I was told.

I'll double check the fluids, modulator and vacuum lines OR have the tranny place do it tomorrow!!
If you are going to use the GT transmission you have to use it in a GT as the shift linkage is on the wrong side for a Manta or Ascona
 

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In my experience about 80% of issues with auto transmissions are fluid related and over half of them are because the owner didn't know how to check the level properly. Just to make sure we rule that out, you did check the level in the transmission with the engine running and in neutral, right? With the engine running the oil is pumped around the transmission, and the torque converter is filled up, which both lower level as you would read it with the dipstick. Since you never know on a shut down transmission how much of that has bled or drained back to the pan, the only way to make sure you are consistantly measuring level is to do it with those things all filled from the engine running.

I have a couple of good automatics I can bring to Carlisle if need be.
 

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'Kickdown' Cable

The adjustment of the kickdown cable which links to the throttle mechanisim is critical as it has a major inflence upon internal fluid presures.

As the rubber grommets in the throttle linkage wear the cable adjustment goes out of whack and needs re-adjustment ... see the FSM for details.
 

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The adjustment of the kickdown cable which links to the throttle mechanisim is critical as it has a major inflence upon internal fluid presures.

As the rubber grommets in the throttle linkage wear the cable adjustment goes out of whack and needs re-adjustment ... see the FSM for details.
I was thinking of something similar myself. I had one without the kickdown cable and it shifted very fast. It was probably in third gear by 15 mph.

Harold
 

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...... you did check the level in the transmission with the engine running and in neutral.......
and at operating temperature!!!!!!!

that the automatic doesn't shift properly, could be that there is no vacuum to the automatic, either the tube is lose or a hose is torn, or the vacuum tube is clogged
 

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Discussion Starter #11
Just got home from work and will look at all of these things before darkness or raqin sets in. I can't work in the garage because I still have the GT up on jack stands. I thought that you just checked the fluid level when it was hot, not running. You can teach an old dog new tricks.
 

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Discussion Starter #12
Duhhhhhhhhhhhhhhhhhhhh!

OK, I got a chance to jack the car up, located the modulator, new one in hand, started to remove the rubber vacuum end and it was cracked in three places big time!! Went to Auto Zone bought a foot of hose, put it on, lowered the car, backed out of the driveway and the tranny worked perfectly.

Forty (40) cents worth of [email protected]%$*?:banghead:

:lmao::lmao:

Thanks for all of the help or I wouldn't of known what to look for.
 

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Dave;
I feel for ya. I have a 1 1/2" section of fuel hose, sitting on my desk here, that took me weeks and several fuel pumps, pulling the tank and not to mention countless hours of wrenching and CUSSING to find. Keep it with your other "problems" to remind yourself to look for the simple things first.
 

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Dave while you replaced the lower section of vacuum hose to the modulator replace the top section of hose to the manifold also. At the meet in Germany there was a GT that had the same problem it would not shift, and OPELENVY missed out on checking old race track. Dennis and I where off in a distance watching the masses huddle around the GT scratching their heads as to why it would not shift. We where approached by one of the Netherland Club members about the problem the GT was having, being from the "Friendly State of Texas" but more so a fellow OPEL-ler I obliged myself and went to take a look, the vacuum line had came off and at the manifold really hard to have seen with the heat shield in place, I slipped it back on checked the line at the modulator, got up and told the owner it was fixed to take it for a short test drive to check it out after showing them what had happened. Up on their return they obtained a new section of vacuum hose and where elated for it was a long drive back to the Netherland form Stuttgart. Thanks to Dennis also as we had discussed a wide realm of possible causes and decided it could only be one.
 

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Discussion Starter #16
I was thinking along the same lines (no pun intended) to check the other end.

BUT

I was so excited to have the car going I couldn't resist taking it for a 15 mile cruise and then the rains came in, so tomorrow I'll check it out. Look out now that the Manta is road worthy, I may just have to work more on the GT!:lmao:
 

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I was thinking along the same lines (no pun intended) to check the other end.

BUT

I was so excited to have the car going I couldn't resist taking it for a 15 mile cruise and then the rains came in, so tomorrow I'll check it out. Look out now that the Manta is road worthy, I may just have to work more on the GT!:lmao:
Dave,
Good to hear you're back on the road with your Manta! While you're familiar with the underside, you should do your car a favor, go ahead and change the fluid and find a new tranny filter.

Jim
 

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I have been doing some test drives around my neighborhood and am having issues with the auto not shifting from 1 to 2 to 3. Transmission was fully rebuilt in 2009 and has had very limited miles on it since 2013 when I started down an engine rebuild and life took priorities of my car. When rebuilding the motor I had Coen Engineering rework/rebuild my converter to have a stall around 2500ish (if my memory serves). The car has sat for a long time in garages not being driven and now that I’m ready to drive it, the transmission doesn’t want to shift. My vacuum line is hooked up at a fitting on the Holley Sniper instead of on the manifold. Could this be causing an issue of the transmission not getting enough vacuum to shift? I have a Cannon intake manifold and it didn’t come with a vacuum tree fitting, so I have the threaded hole fitted with a threaded plug that has been wrapped using fuel grade Teflon tape. Any thoughts?
 

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Just Some Dude in Jersey
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If your hose is plugged onto the modulator well and the modulator is healthy, as well as, the hose, then the problem is probably not enough vacuum. These trannies are sensitive to poor vacuum. If you use a Combo cam they will upshift and downshift prematurely. Your problem is probably with plugging the hose into your Holley. It should be connected to a manifold port. Go to the auto store and get a T-fitting with a 1/4" barb sticking out of a 1/2" T and splice that into your brake booster line. I have had to do this will all my down draft/side draft/and FI set ups. Make sure to get a metal or brass one, do not buy a plastic one, they break. If you can't find that 1/4"/1/2" combo, then go to a hardware store, like ACE, and mix and match barbed brass plumbing fittings to make what you need.
 

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Read postings 1 thru 17 there are numerous solutions written, one or more of then may work
 
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