Glad to see your car still up and running. I can't help with your problem, but wish you the best.

Sent from my SM-N960U using Tapatalk

 

Lol thanks. Plenty of help here if I really need it. Just want to know if anyone dissected the monstrosity hybrid throttle body thanks
Kburger

 

Has anyone attempted this?

What exactly is the problem or error codes?

 

Sorry for my ignorance.... is your setup different from an 02 m54b30? You mention hybrid cable and drive by wire. Mine is all drive by wire.

 

Yes, from what I understand the early ones have a cable from the pedal to the throttle body that attaches to a potentiometer that then converts the mechanical throttle input into an electrical signal transmitted by wire to the electronic throttle actuator ... or something along those lines ... it's kinda nuts ...

 

You wouldn't be having an issue with the round two-stage connector down there, would you? First time I did it, thought I had it right, but it wasn't. ...and of course an electrical cleaning spray wouldn't hurt.

I'm sure it's not this, but just in case.

...and a bump. Got to save the granddad of e46s!

 

I think I mentioned this before. But if Kburger is having repeated problems with his M52TU throttle body (used only in '99 & '00), and has already tried replacing it with a replacement, it is likely not his throttle body, but the wiring in the stupid round 10-pin connector on the harness. The back of that connector, and its pins/wirings is open to the elements in the air flow around the engine block and easily degrades, causing tiny changes in millivolts sent/received between DME and throttle body (aka MDK), throwing the car into limp mode.

I have replaced the throttle body on my M52TU e39 six or seven times.

Here is a solution:

Electronic Throttle Faults & Repair

Diagnosing electronic throttle body faults and replacing its connector plug on 99-00 BMW 5 series.

www.frankies-bmw.com

You could also try a used engine harness, but it will soon have the same problem. Several years ago, I looked into a new Genuine harness...according to my dealer parts counter, it had to be ordered from Germany and it was $750.

I haven't fixed my car yet..its in storage, but one idea I have, is to get the parts referred to in the link above, find a used harness - make sure its the correct one..year/model/trans, have the repair done professionally by an electronics specialist (I suck at wiring/soldering) and replace the harness. This will minimize down time.

 

I think I mentioned this before. But if Kburger is having repeated problems with his M52TU throttle body (used only in '99 & '00), and has already tried replacing it with a replacement, it is likely not his throttle body, but the wiring in the stupid round 10-pin connector on the harness. The back of that connector, and its pins/wirings is open to the elements in the air flow around the engine block and easily degrades, causing tiny changes in millivolts sent/received between DME and throttle body (aka MDK), throwing the car into limp mode.

I have replaced the throttle body on my M52TU e39 six or seven times.

Here is a solution:

Electronic Throttle Faults & Repair

Diagnosing electronic throttle body faults and replacing its connector plug on 99-00 BMW 5 series.

www.frankies-bmw.com

You could also try a used engine harness, but it will soon have the same problem. Several years ago, I looked into a new Genuine harness...according to my dealer parts counter, it had to be ordered from Germany and it was $750.

I haven't fixed my car yet..its in storage, but one idea I have, is to get the parts referred to in the link above, find a used harness - make sure its the correct one..year/model/trans, have the repair done professionally by an electronics specialist (I suck at wiring/soldering) and replace the harness. This will minimize down time.

I have a spare complete engine harness. I examined the back of the connector carefully it does not look like dirt can get to the front where the female pins are. This would make the solution link posted above useless because it only seals the back of the connector not the front. Has anyone completely dissected it? It is a very nice write up however.
Kburger

 

Excellent intelligent replies thank you all. Cleaning the sh** out of the round connector my codes then shifted to icv. After pulling the boot about 10 times, no exaggeration it finally tore at the ICV ring clamp. It was original guess I can't complain. Cleaned ICV wasn't that dirty. Clacked nicely, still ICV errors. Lubed with Wurth HH plus. Best lubricant for anything BTW. I didn't want to lube it but running out of ideas. New icv and boot coming today. Codes are icv mechanical fault. ICV air leak. Will update what I find. I have another thread for heater bypass hose I think that one is my ihka head unit. Always working on this car. Thanks

kburger

 

Sorry. How come in my profile I cannot find my own threads ? I think I saw a bump. In my

 

Very frustrated with editing messages sorry. On topic to me a potentiometer, or pot, varies current as you spin a knob. Many variations in that of course. So, all those wires on the TB, are they basically positions on a pot? As the TB rotates with the cable it hits each position on the pot which activates each wire, just a high/low voltage?

 

…to me a potentiometer, or pot, varies current as you spin a knob. Many variations in that of course. So, all those wires on the TB, are they basically positions on a pot? As the TB rotates with the cable it hits each position on the pot which activates each wire, just a high/low voltage?

Download this document, then start reading on page 11.

https://www.bimmerfest.com/attachments/bmw_e39_siemens_ms42_ms43_m52tu_m54_ecm_engine_control_module_management_systems-pdf.441295

Throttle valve wiring diagram.

BMW WDS Online

bmw wds online for all browsers

bmwteka.com

 

Drove for several miles. Sitting at idle went into limp mode again. Codes only point to throttle body. Of course. Gonna replace ICV hopefully gets here soon.

 

if you have already replaced the TB, the wiring and that 10-pin connector is your problem.

 

Agreed. Pretty sure I already have that wiring diagram of the TB in my Bentley manual. Would love someone to explain to me what each of the 10 wires is doing. Is each wire part of the potentiometer? Does the voltage vary on each wire or is it just on/off high low?
Kburger

 

Engine throttle
With the aid of the actuator of the throttle valve, the throttle valve can be opened independently of the accelerator pedal position.
The motor throttle valve in the M52 and MS42 differs from electronic engine management (EML) in the following points:

-	No potentiometer on accelerator pedal but rather a double potentiometer on the pulley of the motor-driven throttle valve
-	There is a Bowden cable fitted between the accelerator pedal and motor-driven throttle valve which is also used for emergency operation purposes.

Deleting adaptations on completion of repair (M52):
The adaptations should generally not be deleted on completion of repairs (parts replacement). After replacing the throttle valve (MDK) the adaptation values should be deleted in order to avoid a fault code entry.

 

Throttle body output stage cutoff after diagnostic error. What exactly is the output stage and what is the diagnostic that is failing ?

 

Finally took off cowling for ecu shoulda done that days ago. Lazy🤓

 

Been workin on this car 15 years. You get used to doing things a certain way. Taking the TB/ICV boots off in sections and removing the ECU cowling makes it so much easier. Shoulda done that before I started bitchin🤓

 

TB 10 pin magic. Get the he liquid you get a lot more.

 

Hope that helps...you ARE resetting throttle adaptations after you install a replacement TB, right ?

I use INPA

 

Hope that helps...you ARE resetting throttle adaptations after you install a replacement TB, right ?

I use INPA

Yessir!!🤓 I removed the yellow seal inside wire harness connector. Understand that seal is there for a reason. Much easier to screw TB connector onto TB. I think I'm gonna wrap it from the TB to harness with F4 tape. Another amazing product. I always unbolt TB before removing connector anyway. I think the F4 tape will keep it clean.

 

When I had a problem with my TB I used a multi-meter to determine there were electrical issues. See the thread here...

Throttle body trouble codes

I have a 2000 328ci with a cable operated throttle body (different than wire operated throttle bodies on 2001 and later models). Over the past few years I have been getting engine trouble codes that point to problems with my throttle body. When a trouble code occurred all three lights would...

www.e46fanatics.com

I was unable to fix the electrical issues so I bought a good used one and tested it before installing it. All is well now.

 

I keep a roll of F4 tape in all my cars.
You may need "Stabilant" brand contact cleaner.
Expensive stuff but works for connection issues if..... that's your issue?
This is what they use at the dealership.

 

Good advice thanks. The deoxit gold liquid is like nail polish applicator. Precise application to each pin. You should try it. So yeah. Spent way too much time as always. But 730,000 miles can't complain. Just drove it 4 hours to ocean city Maryland. So my daughter got to keep her car at home. Spent a lot of money on parts I didn't need. But I have spares and will use them some day. Got a new ac evaporator fixed my Ac without that. Thank god. Some day I'll use it. I love when it's time to fix the car and I already have the parts. Thanks for everyone's help. Gotta remember to wrap TB connection with F4.
kburger

 

I have a 2000 323i with 111,815 miles. Everything is operating well, if you need some tests, photos or some info from a running Florida donor.

 

Thank you. Lotta good people here willing to help.
kburger

 

Love to see updates from your car whenever you post! I have a buddy with a 2000 528i M52TU that has 450,000 miles on the ODO, and perhaps he has run into similar issue, but from what I recall, all of his problems with the throttle body had to do with one tiny little grommet that fails over time and when it fails there are all sorts of issues with the throttle. This is not something that tossed a code I don't think. But I will check.

Sounds like what you did with the dielectric grease and tape wrapping may have done the trick?

 

Always a debate with dielectric grease. I don't think it improves connections but it seals them so nothing gets in there. DEOXIT is a liquid specifically designed to improve electric connections. It comes in tiny spray bottle but I highly recommend the liquid small nail polish style. You can pinpoint apply it to each pin without getting it on anything else. Bunch of deoxit products on the market depends on how bad the pins are. I recommend for throttle body pins both sides brake cleaner then air compressor to dry both. Then deoxit gold with nail polish applicator to each pin on both sides male and female. Careful with brake cleaner of course nasty and flammable.
kburger

 

I checked with him, and he said 1000000% this is your problem. He got tons of codes, similar to yours, and it was not the pin connector, it was this specific grommet that turned into rubber goo over time and could not support the cable itself.

BMW Grommet F Accelerator Bowden Cable - Genuine BMW 35411164739

BMW Grommet F Accelerator Bowden Cable - Genuine BMW 35411164739

www.fcpeuro.com

#14 here

Amazon.com: BMW Genuine Accelerator Pedal/Bowden Cable Grommet F Accelerator Bowden Cable 528i 323Ci 323i 328Ci 328i : Automotive

Buy BMW Genuine Accelerator Pedal/Bowden Cable Grommet F Accelerator Bowden Cable 528i 323Ci 323i 328Ci 328i: Accelerator Cables - Amazon.com ✓ FREE DELIVERY possible on eligible purchases

www.amazon.com

 

I checked with him, and he said 1000000% this is your problem. He got tons of codes, similar to yours, and it was not the pin connector, it was this specific grommet that turned into rubber goo over time and could not support the cable itself.

Thanks for sharing that issue...It is certainly worth making sure that grommet is intact, AND that the cable is properly adjusted (Bentley E39 manual has instructions). Replacing the grommet is a relatively cheap and easy thing to do.

However, I remain convinced that there are widespread problems with the M52TU 10-pin connector and its connections..Several people have replaced harnesses, or just that connector and its wiring, and have had the problem go away.

 

you can see this grommet directly to the right of the ICV

 

claims this led to limp mode several times, as if there is even the slightest play with that cable, the car will toss all sorts of codes. Please check and report back asap. Many times this is overlooked as you are hyper focused on electrical items due to the codes, and would never think this rubber piece tied to the mechanical cable would be the culprit.

I remember him screaming for joy when he found this as he was certain his ECU might be fried or having issues. He was overjoyed to fix his car for a few bucks.

 

I've had a few connectors with corrosion which eventually leads to a poor/intermittent connections and eventually wires breaking inside insulation, etc. Before cutting and splicing, I always try a vigorous cleaning. Unless the connectors are in extremely bad shape, this method has worked for me many times.

What you will need:

1. Bottle of CLR.
2. Distilled water.
3. IPA (Isopropyl Alcohol 70%)
4. Plastic containers.
5. Plastic and metal safe De-greaser. (I use spray nine)
6. NO-OX-ID conductive grease (Ebay.com around $8).
7. Hot melt glue gun.

As always, read the information on the products you are using to make sure it is safe to use on the materials you want to use it on. If in doubt, don't use it or make sure you cover areas you want to protect.

Testing:

Remove the connectors from the unit. Clean a small area of each connector and one of the wires. Test each cleaner (CLR, IPA, Spray 9) one at a time by placing a few drops on the connector and wire. Let stand for 20 minutes or so, then check each cleaner in turn, to make sure there is no damage to the connector, wire insulation, etc. I've never had any issues using this stuff, but its better to test and not get any surprises.

Procedure:

If the wires and connectors are very oily/greasy dilute the Spray Nine 50/50 with distilled water. Wash the wires with a soft brush and pour some into a container and immerse the connector in it, and let sit for 15 minutes, then use the brush to clean the connector inside and out. Rinse everything with clean water and blow dry.

To remove corrosion from pins wire etc: Fill a clean container with 50/50 distilled water and CLR. Immerse the connector so its fully covered by the liquid. Let it sit for at least 60 minutes. Then remove it, rinse off well with clean water. Then fill container with 50/50 mix IPA and water. Immerse connector for 30 seconds or so, remove and blow dry. Let it sit for 30 minutes to dry completely.

Apply a light coat of grease to each pin. I use the end of a safety pin to put a small bit inside the female pins of the connector. You don't need a lot, a small amount does the job. After you reconnect everything have a good look at the connectors where the wires are inserted. If you pull lightly on each wire and it feels loose, push it in, and add a small dab of hot glue to keep it in place.

 

^^ But dat grommet fix doe. Could be it. Simple to check insanely cheap to fix. Esp if its original and was exposed to engine bay heat for 730,000 miles!