Throttle issue

Berk

Regular Member
Joined
Dec 14, 2025
Points
13
New to the community. 2000 z3 2.8. 116k miles. Looking for help with P1580 code. After cleaning throttle body ( off engine) and ICV the engine will not rev above 3000 RPM. Problem appeared after sitting for 2 months .
 

NZ00Z3

Zorg Guru (IV)
Supporter
New Zealand Zeds
Joined
Dec 9, 2014
Points
158
Location
Timaru, New Zealand
Model of Z
3.0L, 2.8L, 2.0L Z3 Roadsters
Your car being a 2000 2.8, it will have the M52B28tu engine and hybrid MDK throttle body. The throttle bodies play up every now and then.

Have a read through these 2 doc's I've put together on the MDK throttle body to see if you can sort the problem out.

The P1580 code transfers though to several BMW codes, most about the throttle body being mechanically stuck
 

Attachments

Berk

Regular Member
Joined
Dec 14, 2025
Points
13
Your car being a 2000 2.8, it will have the M52B28tu engine and hybrid MDK throttle body. The throttle bodies play up every now and then.

Have a read through these 2 doc's I've put together on the MDK throttle body to see if you can sort the problem out.

The P1580 code transfers though to several BMW codes, most about the throttle body being mechanically stuck
Thanks!
 

shera25

Regular Member
Joined
Sep 12, 2025
Points
13
New to the community. 2000 z3 2.8. 116k miles. Looking for help with P1580 code. After cleaning throttle body ( off engine) and ICV the engine will not rev above 3000 RPM. Problem appeared after sitting for 2 months .
Welcome! 👋 P1580 is often linked to throttle adaptation. After cleaning, it may need a throttle reset or relearn. Try doing an ignition-on reset or disconnecting the battery for a bit, then rescan. Also worth double-checking all intake hoses and connectors around the throttle and ICV in case something was disturbed.
 

Berk

Regular Member
Joined
Dec 14, 2025
Points
13
Welcome! 👋 P1580 is often linked to throttle adaptation. After cleaning, it may need a throttle reset or relearn. Try doing an ignition-on reset or disconnecting the battery for a bit, then rescan. Also worth double-checking all intake hoses and connectors around the throttle and ICV in case something was disturbed.
Thanks for your response! I like this forum!
 

Berk

Regular Member
Joined
Dec 14, 2025
Points
13
Woe is me. Wife reved engine. Throttle body butterfly opens ( watching with mirror in place) but acts starved for air/fuel? ( air box/MAF off for better viewing) . ICV cleaned and clicks if wiggled. 116 k miles, has been sitting under carport 3 months. Last drive was flawless. Suggestions? Fuel filter old. Check fuel pressure? Appreciate any responses.
 

NZ00Z3

Zorg Guru (IV)
Supporter
New Zealand Zeds
Joined
Dec 9, 2014
Points
158
Location
Timaru, New Zealand
Model of Z
3.0L, 2.8L, 2.0L Z3 Roadsters
Was the MAF unplugged during the Rev test?
- If it was still plugged in, then it would not be passing any air and the engine DME would be having a hard time with the fuel/air mixture.
- If it was unplugged (which it should be), then the DME is working off internal air fuel tables. These make the mixture slightly rich.

What trouble codes are you getting now?

If you put the car back together, how does it drive? Still limited to 3,000 rpm?
 

Berk

Regular Member
Joined
Dec 14, 2025
Points
13
Was the MAF unplugged during the Rev test?
- If it was still plugged in, then it would not be passing any air and the engine DME would be having a hard time with the fuel/air mixture.
- If it was unplugged (which it should be), then the DME is working off internal air fuel tables. These make the mixture slightly rich.

What trouble codes are you getting now?

If you put the car back together, how does it drive? Still limited to 3,000 rpm?
P1580,” throttle body stuck.” If I pull it out of driveway it will struggle to get beyond 25mph. ( everything put back in place) Sadly may consider new Throttle Body. This is my first repair on a 25 year old Z3 . Appreciate your responses.
 

NZ00Z3

Zorg Guru (IV)
Supporter
New Zealand Zeds
Joined
Dec 9, 2014
Points
158
Location
Timaru, New Zealand
Model of Z
3.0L, 2.8L, 2.0L Z3 Roadsters
If I pull it out of driveway it will struggle to get beyond 25mph.
That tells me that you are driving on the Idle Control Valve and the main throttle body is not opening.

The MDK throttle bodies are real expensive new. See if you can find a good one second hand.
 
Top