Will not stay running when started when warm unless you give it gas for several seconds

CRHENKEL

MEMBER
2006 BMW Z4
3.0L
6 CYL
2WD
AUTOMATIC
109,000 MILES

So I have replaced lots of engine parts on this car listed above 3.0L roadster. New plugs new ignition coils on each plug. New oil pressure sensor new oil temp new water temp sensors. New OEM Vanos solenoids. All 4 new O2 sensors. New coolant thermostat and new transmission cooler thermostat. New mass air flow sensor. New valve tonic camshaft adjuster motor.

When you start the car cold it starts and stays running on its own. The idle hunts up and down a bit but it overall settles down and stays running and idles. However, once the car has been started and it turned off and you try to restart before the engine sits (and gets clod again I am guessing) when you restart the car the only way to keep it running is to feather the accelerator pedal and give it fuel. With out applying the gas pedal to keep it running for at least 30 seconds the car will shut off. It starts fine and all the time but if the engine is warm you better be ready to give it fuel after turning the key or the engine will stall out. Why and how do it fix it?
My only guess now is maybe the fuel injectors are leaking and causing a rich situation with gurl pooled in the cylinders?Help.

1 Reply

JACOBANDNICKOLAS

MECHANIC
108,289 POSTS

Welcome to 2CarPros.

It sounds like an issue with the idle speed control valve. I will supply the directions for replacing it, but before replacing it, check it for carbon build up or corrosion that can cause it to not function properly. The attached pictures correlate with the directions.

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2006 BMW Z4 3.0si Roadster (E85) L6-3.0L (N52)
Procedures
Vehicle Powertrain Management Fuel Delivery and Air Induction Idle Speed/Throttle Actuator - Electronic Service and Repair Procedures
PROCEDURES
Replacing idle speed control valve (M52TU, M54)

Turn off ignition.
Follow instructions for disconnecting and connecting battery. Disconnect battery negative lead.

Pic 1

M52TU only:
Remove intake filter housing.
Pull Bowden cable upwards out of holder (1) and suspend from throttle.

Pic 2

Release hose clamps (1).
Detach intake hose piece from throttle assembly and idle-speed control valve.

Pic 3

Installation:
To facilitate installation, fit air-mass flow sensor with intake hose (1). Coat intake hose (1) with antiseize agent.

M54 only:
Remove intake hose completely (between intake filter housing and throttle assembly).

M52TU and M54:

pic 4

Disconnect following plug connections:
1 - Resonance flap
2 - Idle-speed control valve

Installation location:

pic 5

Idle actuator (2) is fitted below intake air manifold, directly above throttle (1).

Pic 6

Release screw (1) on cable duct mounting.
Release screws (2) on holder of idle actuator (3).
Remove idle actuator valve with holder from intake air manifold.

Pic 7

Detach idle actuator (2) from rubber retainer (4).
Always replace gasket (1) from idle actuator (2) to intake air manifold. However, during reinstallation, do not fit gasket on idle actuator but install first in intake air manifold.

Installation:

pic 8

Replace gasket (1). To facilitate installation of idle actuator, coat inside of gasket with antiseize agent.

________________________________

Let me know what you find or if you have other questions.

Take care,
Joe

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