Throttle actuator replacement

katter77 · 07-22-2026, 10:05 PM

Hi all,

I've bought a 2008 M3 E90 about 9 months ago. It has 185k miles and rod bearings were done at 80k, so had a shop around me do the rod bearings right away.

I put the car in storage for the winter and took it out a few months ago. I started driving it and the car went into limp mode. Scanned it and found out it was left bank throttle actuators. I figured I'd try to do it myself.

When I went in, I've found a few pretty nuts things (i think), but need a sanity check. Zip ties to keep sensors together, air filter housing box not screwed down, phelem not connected to either vacuum line or fresh air hose. Also, the wiring for AC compressor clutch is floating off of the anchor(?). Not sure if that matters. I'm a little worried about putting it back on.

I'm pretty far along removing everything but now need to cut some zip ties on sensors to get it the electrical housing out of the way and get to the throttle actuators.

Do I send the car back to the shop, tell them what i found and ask them to finish it up and clean up the issues? They're a reputable shop. I'm assuming that these issues/items were likely from them when they did the rod bearings, but please correct me if I'm wrong.

Any thoughts? Id love to do this on my own. I ordered more zip ties (just in case).

Thanks

omgzirra_exe · 07-23-2026, 09:48 AM

i highly doubt the shop did all that just to do rod bearings.. since it has nothing to do with the top of the engine.

Fooksdaddy · 07-23-2026, 10:03 AM

I'd have to agree, nothing on the top end has anything to do with the rod bearings beside refilling the power steering fluid if they did a fluid change from dropping the front subframe.

Most likely scenario was the previous owner was a diy'r and just got stuff to work w/o spending the extra cash to put it back correctly....ie. he broke chit and didn't feel like a replacement was necessary.

nick3753 · 07-23-2026, 07:16 PM

I’ve definitely zip tied some connectors under my plenum when doing my TAs (where the connectors attach to the wiring harness). Damn things become so brittle over time.

katter77 · 07-23-2026, 11:04 PM

Thanks all. I finished the replacement today. Car's running great and no codes!

07-22-2026, 10:05 PM	#1
katter77 Registered 0 Rep 2 Posts Drives: BMW M3 E90 Join Date: Sep 2025 Location: Bedford, NY iTrader: (0)	Throttle actuator replacement - newbie Hi all, I've bought a 2008 M3 E90 about 9 months ago. It has 185k miles and rod bearings were done at 80k, so had a shop around me do the rod bearings right away. I put the car in storage for the winter and took it out a few months ago. I started driving it and the car went into limp mode. Scanned it and found out it was left bank throttle actuators. I figured I'd try to do it myself. When I went in, I've found a few pretty nuts things (i think), but need a sanity check. Zip ties to keep sensors together, air filter housing box not screwed down, phelem not connected to either vacuum line or fresh air hose. Also, the wiring for AC compressor clutch is floating off of the anchor(?). Not sure if that matters. I'm a little worried about putting it back on. I'm pretty far along removing everything but now need to cut some zip ties on sensors to get it the electrical housing out of the way and get to the throttle actuators. Do I send the car back to the shop, tell them what i found and ask them to finish it up and clean up the issues? They're a reputable shop. I'm assuming that these issues/items were likely from them when they did the rod bearings, but please correct me if I'm wrong. Any thoughts? Id love to do this on my own. I ordered more zip ties (just in case). Thanks
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07-23-2026, 09:48 AM	#2
omgzirra_exe Colonel 3057 Rep 2,621 Posts Drives: 4.4L M3, 1JZGTE IS300, N55B30 Join Date: Jun 2019 Location: BMW, M3 iTrader: (0)	i highly doubt the shop did all that just to do rod bearings.. since it has nothing to do with the top of the engine. __________________ Build: ZillaSpec M3 N1 Build M3Post Track General Discussion: Discord #fakeGTS
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07-23-2026, 10:03 AM	#3
Fooksdaddy First Lieutenant 158 Rep 303 Posts Drives: 2011 BMW M3 SSII Join Date: May 2016 Location: San Antonio iTrader: (3)	I'd have to agree, nothing on the top end has anything to do with the rod bearings beside refilling the power steering fluid if they did a fluid change from dropping the front subframe. Most likely scenario was the previous owner was a diy'r and just got stuff to work w/o spending the extra cash to put it back correctly....ie. he broke chit and didn't feel like a replacement was necessary. __________________ E90 ///M3 Silverstone II '11 (current) E90 ///M3 Silverstone II '08 E46 ///M3 Alpine White III E36 ///M3 Arctic Silver E46 ///M3 Carbon Schwartz
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07-23-2026, 07:16 PM	#4
nick3753 Lieutenant Colonel 1269 Rep 1,613 Posts Drives: 2012 e92 M3 DCT ZCP Join Date: Oct 2010 Location: Michigan iTrader: (0) Garage List 2017 Audi S6 [0.00] 1997 BMW 328i Touring [0.00] 2012 BMW M3 [0.00]	I’ve definitely zip tied some connectors under my plenum when doing my TAs (where the connectors attach to the wiring harness). Damn things become so brittle over time.
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07-23-2026, 11:04 PM	#5
katter77 Registered 0 Rep 2 Posts Drives: BMW M3 E90 Join Date: Sep 2025 Location: Bedford, NY iTrader: (0)	Thanks all. I finished the replacement today. Car's running great and no codes!
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