Automatic transmission not engage
07-23-2021, 07:19 AM
#301
Racer
Thread Starter
Hi Greg,
Since it’s not an expensive part, I will change my valve. But I don’t know if it’s the root cause of my problem when ATF is cold.
Since it’s not an expensive part, I will change my valve. But I don’t know if it’s the root cause of my problem when ATF is cold.
07-23-2021, 08:06 PM
#302
Racer
Thread Starter
When hot, all is good. Speed and rpm increase. Shift change.
07-23-2021, 10:09 PM
#303
Former Vendor
There is an internal temperature restriction part.
It sits in the case, just above the valve body.
It's red in color and surrounded by rubber to hold it in place and seal around it.
It's a simple orifice that restricts flow until the oil gets warm.
They come in at least two different orifice sizes, which changed in 1987, in the 928 transmission. (Early 4 speeds had less restriction, as I recall....I'd need to actually look at the two different ones, on the shelf.)
Worth nothing this restrictor only goes in one way....and it is tough to get it in incorrectly.
However, this restrictor will be sensitive to the thickness of the transmission fluid.
Is your fluid thicker than regular old dyno oil Dextron II?
If so, you may want to try the bigger of the two orifices.
It sits in the case, just above the valve body.
It's red in color and surrounded by rubber to hold it in place and seal around it.
It's a simple orifice that restricts flow until the oil gets warm.
They come in at least two different orifice sizes, which changed in 1987, in the 928 transmission. (Early 4 speeds had less restriction, as I recall....I'd need to actually look at the two different ones, on the shelf.)
Worth nothing this restrictor only goes in one way....and it is tough to get it in incorrectly.
However, this restrictor will be sensitive to the thickness of the transmission fluid.
Is your fluid thicker than regular old dyno oil Dextron II?
If so, you may want to try the bigger of the two orifices.
07-23-2021, 10:40 PM
#304
Racer
Thread Starter
Merci Greg for all these informations.
When Porsche France changed ATF at 70000 km, they used DEXRON III. At 140 000 km I use also DEXRON III.
BTW. This is my ATF level when hot with shift on N.
When Porsche France changed ATF at 70000 km, they used DEXRON III. At 140 000 km I use also DEXRON III.
BTW. This is my ATF level when hot with shift on N.
07-24-2021, 03:46 AM
#305
Rennlist Member
Ya know...two days ago I was going to ask if your fluid was full...
it's -not-.
THIS is full when hot.
You are a number of quarts low...this leads to all sorts of madness.
it's -not-.
THIS is full when hot.
You are a number of quarts low...this leads to all sorts of madness.
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Fabien92 (07-24-2021)
07-24-2021, 04:22 AM
#306
Former Vendor
Absolutely correct.
Jeff to the rescue!
Little wonder it slips, when cold....your pan is almost empty.
Pour in 2 more quarts (liters) before driving again.
Fill the transmission between the min and max lines, when hot.
.....that's really pretty looking ATF, BTW!
Last edited by GregBBRD; 07-24-2021 at 04:28 AM.
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Fabien92 (07-24-2021)
07-25-2021, 06:37 AM
#307
Racer
Thread Starter
Addition of 0.8 liter (1 quarter) Nothing better. We will add more ATF (1 liter) on wednesday.
Picture when cold in N after 4 seconds in each position R N D N R N D N.
Picture when cold in N after 4 seconds in each position R N D N R N D N.
07-25-2021, 07:20 AM
#308
Rennlist Member
Looking better already! I check my ATF when fully warned up but you'll get different opinions about this. I think the WSM wants you to check it when cold.
In my experience is not enough to let it warm up when idling and shifting through the gears while stationary. Drive and check after a few miles and use the quick fill port to make it easy.
In my experience is not enough to let it warm up when idling and shifting through the gears while stationary. Drive and check after a few miles and use the quick fill port to make it easy.
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Fabien92 (07-25-2021)
07-25-2021, 07:46 AM
#309
Racer
Thread Starter
It’s why I wait on wednesday to drive on 10 km and to lift the GTS. We will use thé quick fill port.
Today I added ATF at home with jacks through ATF tank. It’s not the best way.
How do you check ATF level ? With shift on N ?
07-25-2021, 09:04 AM
#310
Rennlist Member
On level ground, everything is fully warmed up, gear selector either in P or N.
Fill in ATF slowly, it's easy to overfill. The level markings are located nearby the expansion tank cap.
Fill in ATF slowly, it's easy to overfill. The level markings are located nearby the expansion tank cap.
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Fabien92 (07-25-2021)
07-25-2021, 02:52 PM
#313
Former Vendor
Yes, you are still way too low on fluid.
Although I can not see markings on your reservoir, there's generally a "cold" mark on the reservoir to get you close to the proper cold level... about midway.
After getting the transmission hot, "top off" so the level is between the "min" and "max" marks, which are very close to the very top of the reservoir.
Although I can not see markings on your reservoir, there's generally a "cold" mark on the reservoir to get you close to the proper cold level... about midway.
After getting the transmission hot, "top off" so the level is between the "min" and "max" marks, which are very close to the very top of the reservoir.
Last edited by GregBBRD; 07-25-2021 at 03:00 PM.
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Fabien92 (07-25-2021)
07-25-2021, 04:03 PM
#314
Rennlist Member
That view is from the rear of the car. I copied the levels from the front of the tank so I could top off with the quick fill port with the car on the ground so it’s level and not be under the car with the engine running.
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Fabien92 (07-25-2021)
07-25-2021, 05:19 PM
#315
Racer
Thread Starter