Voltage fluctuations stuff going out and bad acceleration!

[Monn96]

could someone please tell me if this is normal before heading to the dealership https://www.youtube.com/watch?v=-EKNL3LF2Ng i captured the voltage going up and down, i did a before ignition , and then ignition at idle, hit the lights on and off tried the claxon and its a no go, the claxon keeps coming back. i also revved it so test the voltage further, I DONT KNOW CORRECT VALUES PLEASE HELP CAR IS ACING FUNNY AND WEIRED :confused:
Car is a 90 525i Automatic M50b25

[shogun]

The alternator works well, the voltage is high and flutuates depending on the needs of the consumers switched on and car battery state.
The light in the cluster going out is a different thing. Maybe the bulbs have no good contact or the cluster ground. When the light goes off in the cluster next time, slap the the dash above the cluster slightly with your hand, light might come back then.
Bad acceleration is again another item to be discussed.
Explain that more in detail and let us know what you have checked/changed so far

[Monn96]

Thanks for the very fast reply, yeah i forgot to say that bulb also goes out and come back by it self, i dunno i feel like all these symptoms are prone to a main problem :/ , maybe i should have said more detail, well first of all car was doing great then one day after putting gas the trans program message came in and unfort. i had to drive it with that error with transmission on 3rd or 4th gear.. until the error went by itself after letting it sit for a while but i went down and checked the trans electric plug underneath the car cleaned it. and it works fine, but since that day i had bad idle and when coming to a stop the car jerks a bit and the rpm goes a lil up and then down, claxon works intermittently but when it goes out it sounds like it wants to work but it can't not just not working at all! i hooked it to a scanner and it all got is a transmission speed sensor or something like that :/ car feels like it has no power acceleration is very bad in 3rd or 4th gear! i dunno where to start i feel very bad about this.. ( it only accelerated when kicked down but still not powerful )
ANOTHER IMPORTANT THING ... it doesn't have the check control module it has been stolen and will get one from ebay soon, so thats why nothing is filckering in the dash or any error message comes up :)

[shogun]

It may not be a problem of the transmission. The trans program = limpmode also comes on when some other items are not working properly and it switches to limpmode = 3rd gear to protect the drive system.
But as you mention that the scanner tells you transmission speed sensor, then you have to change the speed sensor in the transmission, for that you have to remove the transmission oil pan and the transmission filter.
What is the VIN number of your car? Or check with your VIN here for the correct part http://www.realoem.com/bmw/select.do

As for the stolen check control module, that I do not understand. The check control is part of your cluster and in the youtube I can see it. You have to change the broken bulbs in the cluster, then you also see the check control again.

Also unclear is: you mention 6-speed (bmw e34 525i 6sp), but then you talk about stays in 3rd gear. I assume you have not an manual 6-speed gear but an automatic transmission, and in case your car is EURO spec. it is a 5-speed ZF 5HP18 (most probably, but this version had some automatic transmission based on country. Check based on your VIN or check the name tag on the transmission.

[Monn96]

i don't know how the 6sp thing happen xD i corrected it, i have the ZF 5HP18 ​

[shogun]

5HP18 speed sensor, probably this one, ZF part number Product ID : 0501 311 086 01 http://www.thectsc.com/products/speed-sensor-5hp18/19/24-4-11.html
read this https://www.bimmerforums.com/forum/showthread.php?2193811-ZF-5HP18-Transmission-Code-Errors
http://www.bmwe34.net/E34main/Trouble/TransProgram.htm

download these 3 BIG files
http://www.all-trans.by/assets/site/files/zf/5hp18.pdf
https://www.bmwe34.net/E34main/Trouble/Data/ZF%20Tech%20Guide.pdf
http://shop.ukrtrans.biz/wp-content/uploads/catalogs/ZF5HP18.pdf3

[Monn96]

Thank you will check em

[Monn96]

So the problem was funny, it was the earth battery cable!! so no more voltage fluctuations but the horn was legit bad so i bought a new horn, and also the light that goes out randomly in the cluster is a separate thing too, the idle thing i am currently suspecting the MAF so i will get there and clean it and see if its the reason for the jerky hesitating idle, thanks guys for the help.

[The Chauffeur]

Good to hear you got it sorted out! And now that you're mentioning the earth battery cable: if you have an engine bay-mounted battery, the earth cable is in a very bad place, very exposed to the heat and road splash, so it gets cracked and damaged more easily...

And here's another thought: I was experiencing a kind of "lazy" start, which makes you think the starter or alternator are going out... The PO had the negative battery cable replaced with a very long and thin one, so I replaced it with a very thick-gauge, short one. Now the start feels very "healthy" (that's the best way I can describe it) and even my idle feels more stable.

Not suggesting that's the idle problem you're experiencing, but if your earth cable was bad, it wouldn't do any damage to check the other ones, just my 2 cents!