1990 525 not shifting?

[94blackmamba]

1990 525i with auto trans. (Not computer aided in any way) Ok so in the morning when it's cold it doesn't want to shift out of 1st gear until high rpms. But after it shifts that one time it shifts normally for the rest of the day. The trans doesn't slip, has a fresh fluid change and filter but I'm thinking it might be a sticky shuttle valve? Any input on repairing this? Or is it gonna need a whole new valve body?

[ross1]

Is this a recent development or is the car new to you? Do you start up and drive off right away?
I cannot remember if your model operates this way but many cars are "programmed" to quickly heat up the catalytic converters to minimize emissions. Holding the car in first revs the engine higher heating the cats quicker.
If your first shift after a cold start won't occur until 3k or so and then shifts normally I suspect this is what you are seeing.
I prefer not to rev a cold engine like that so a few moments running before driving off will allow the cats to heat at idle.

[94blackmamba]

Considering this auto transmission doesn't have a computer and has no electronics at all other than the neutral safety switch and reverse light switch I don't think it is normal behavior. And it won't shift until like 5k rpm. Warm or cold makes no difference. I've tried letting it idle for 15 mins with the same result. But once it makes that first shift there are no problems for the rest of the trip. If the engine is allowed to cool (8 hour work shift) it will do it once more but again after it shifts that first time it will shift normally and at a much lower rpm (1500rpm) when driven conservatively.

[shogun]

It is even mentioned in the owners manual, that the car is programmed like that to heat up quickly to operating temperature, but 5000 RPM is too high.
And this auto transmission has a transmission control module and the valve body has electric control solenoids, speed sensors etc pp.

Ever changed the trans fluid and filter? Did you check fluid level correct?
Clean the metal screen in front of the pressure solenoid in the valve body , this is for example for the 4HP ZF https://www.bimmerforums.com/forum/s...hifting-solved
speed sensor could be not functioning.
Or find someone which can read fault codes on the trans, that is not done with a simple Peake fault code reader.

[whiskychaser]

If you have a simple 4HP22 hydraulic transmission and not the EH, the governor may be worn or dirty. Or the 1-2 shift valve may be sticking. You can get at the valve body by dropping the pan. But the governor lives in the rear end of the trans. So you will probably have to drop the prop shaft, remove the output flange and back end of the case to get at it

[shogun]

Car is based on his profile 1994 530, do not know the VIN, assuming US 530 M60B30 based on ETK it has a A5S310Z = 5HP18, if there was a M60B30 in USA at all.

On the other hand he says 1990 525. That would be a simple 4HP22 - FA based on ETK. Need more details on VIN and trans.

[Sir Montalbon]

Check your tire pressures and check if your tires are all same size/brand. Your symptoms don't quite check all the boxes for this, but it's only a few minutes and free...

TSB 24 05 97
^ Transmission will not shift out of 3rd gear. ^ After downshifting at freeway speeds, transmission will not up-shift beyond 3rd gear. Cause:
The AGS curve recognition feature which inhibits transmission up-shifts while cornering has been erroneously activated. The up-shift prevention (curve recognition) is activated by a software defined difference in wheel speed on the front tires. Different wheel speeds can be caused by: ^ Tires are inflated unequally. ^ Tires are different in size. ^ Tires are the same size but are a different brand or make. ^ Tires are worn unequally. Correction:
Check the front tires for: ^ Proper inflation. ^ Left and right tire are the same size, brand and make. Left and right tire are worn equally. Procedure:
In case of unequally worn, different size, brand or make of tires, it may be necessary to swap front and rear tires to prevent the false activation of the curve recognition feature. The customer should be advised of the findings and condition of the tires.