Rough idle no code at times pls help

mikestark · 02-17-2019, 03:37 PM

05 bmw z4 3.0 e85...m54 . every now and then the car will idle rough like it s about to die as if my clutch is being released with no gas. No engine light. I have cleaned the idle control valve, the maf, new sparks, cleaned the vanos, cleaned kn air filter and ran some fuel cleaner through the system....

What’s next... clean the throttle body or fuel injectors??? Please, advise!

Huz-Z · 02-17-2019, 06:12 PM

Dirty fuel filter? Bad tank of gas?

RossBMWZseries · 02-17-2019, 10:40 PM

Clean the throttle body as that’s your cheapest option. Maybe could be the Fuel filter? Ignition coils? Try using some Techron when your gas tank is empty

Steeler · 02-18-2019, 09:26 AM

Coils?

mikestark · 02-18-2019, 07:56 PM

Wouldn t fuel filter have way more symptoms? Mpg is still 23 average drives great just once a week or so it will be a rough idle. No codes still. I will be cleaning the throttle this weekend. If that doesn t work then the coils and if not then the 5 hour fuel pump job. Ill post back.

pokeybritches · 02-18-2019, 08:30 PM

Have you checked for vacuum leaks?

What are your fuel trims at idle?

mikestark · 02-19-2019, 07:27 AM

What tool do i need to figure fuel trims? I wouldn’t doubt a vaccuum leak; I have changed the throttle body boot bc it was crumbling apart and the secondary air injection hose bc it was cracked, both within the last 1 month. The throttle body boot threw a code and the air injection hose did not. I just noticed the air injection hose blowing air out at me while under the hood.

mikestark · 02-19-2019, 09:55 AM

After reading the bellow article I realized i do have a small whistle... anyone have a link to the ccv replacement?

The BMW crankcase vent system separates liquid oil from the air inside the engine and intake. When working correctly, oil is removed from the intake air and returned to the oil pan. Oil vapor remains and is burned up in the combustion chamber. Every car has some form of crankcase ventilation, also known as a PCV, CCV, oil separator, and a cyclonic separator. BMW CCV system are notoriously failure prone, leading to high oil consumption, burning oil, loss of power, misfiring, and high carbon deposits. The problems are worse on the turbocharged models where the CCV needs to keep up with the pressure from the turbocharger(s). An overhaul of the CCV system should be planned every couple of years and especially before the winter months. Signs of a failing CCV include: whistling noises in the intake, blueish smoke in the exhaust, high oil consumption, and thick white or yellow gunk under the oil cap.

02-17-2019, 03:37 PM	#1
mikestark New Member 0 Rep 17 Posts Drives: 2005 BMW Z4 Join Date: Dec 2018 Location: largo florida iTrader: (0)	Rough idle no code at times pls help 05 bmw z4 3.0 e85...m54 . every now and then the car will idle rough like it s about to die as if my clutch is being released with no gas. No engine light. I have cleaned the idle control valve, the maf, new sparks, cleaned the vanos, cleaned kn air filter and ran some fuel cleaner through the system.... What’s next... clean the throttle body or fuel injectors??? Please, advise! Last edited by mikestark; 02-17-2019 at 05:06 PM..
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02-17-2019, 06:12 PM	#2
Huz-Z Brigadier General 851 Rep 4,057 Posts Drives: Z4 3.0si, 328 XDrive, X5 35i Join Date: Aug 2009 Location: Canada iTrader: (0)	Dirty fuel filter? Bad tank of gas?
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02-17-2019, 10:40 PM	#3
RossBMWZseries Major 224 Rep 1,130 Posts Drives: '11 E92 328i LCI & '06 Z4MR Join Date: Jun 2014 Location: San Juan TX iTrader: (1) Garage List 2006 BMW Z4M Roadster [7.00]	Clean the throttle body as that’s your cheapest option. Maybe could be the Fuel filter? Ignition coils? Try using some Techron when your gas tank is empty __________________ 2014 BMW X5 Sdrive35i F15 2011 BMW 328i E92 LCI 2006 BMW Z4 M Roadster E85 2013 BMW S1000RR K46 R.I.P. 1998 BMW Z3 Roadster 1.9L E36 SOLD
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02-18-2019, 09:26 AM	#4
Steeler Colonel 2428 Rep 2,704 Posts Drives: Built not Bought 04 Z4 VF Join Date: Feb 2013 Location: Kitchener Ontario Canada iTrader: (2)	Coils? __________________ W2A Intercooled Vortech V3Si, custom ducting, Alpha N, 60# Bosch,2.62 pulley, multi port WMI, Severn Tuning(pokeybritches), Tial, magnaflow,SS race muffler, 42 design,3.91LSD, H&R, Hotchkis,ST coils,Konis, Megan camber arms, AKG SS, Nylon mounts, Poly bushings, Carbon interior, CF Aero.APEX
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02-18-2019, 07:56 PM	#5
mikestark New Member 0 Rep 17 Posts Drives: 2005 BMW Z4 Join Date: Dec 2018 Location: largo florida iTrader: (0)	Wouldn t fuel filter have way more symptoms? Mpg is still 23 average drives great just once a week or so it will be a rough idle. No codes still. I will be cleaning the throttle this weekend. If that doesn t work then the coils and if not then the 5 hour fuel pump job. Ill post back.
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02-18-2019, 08:30 PM	#6
pokeybritches Colonel 479 Rep 2,782 Posts Drives: ESS/G-Power Z4M, VF Z4, 996tt Join Date: Sep 2009 Location: Los Angeles iTrader: (12) Garage List 2006 BMW Z4M [10.00] 2006 BMW Z4M [8.50] 2003 BMW Z4 3.0i [9.00]	Have you checked for vacuum leaks? What are your fuel trims at idle? __________________ VF Engineering Z4 3.0i, ESS Z4M, G-Power Z4M, 996 Turbo
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02-19-2019, 07:27 AM	#7
mikestark New Member 0 Rep 17 Posts Drives: 2005 BMW Z4 Join Date: Dec 2018 Location: largo florida iTrader: (0)	What tool do i need to figure fuel trims? I wouldn’t doubt a vaccuum leak; I have changed the throttle body boot bc it was crumbling apart and the secondary air injection hose bc it was cracked, both within the last 1 month. The throttle body boot threw a code and the air injection hose did not. I just noticed the air injection hose blowing air out at me while under the hood.
	Appreciate 0 Quote

02-19-2019, 09:55 AM	#8
mikestark New Member 0 Rep 17 Posts Drives: 2005 BMW Z4 Join Date: Dec 2018 Location: largo florida iTrader: (0)	After reading the bellow article I realized i do have a small whistle... anyone have a link to the ccv replacement? The BMW crankcase vent system separates liquid oil from the air inside the engine and intake. When working correctly, oil is removed from the intake air and returned to the oil pan. Oil vapor remains and is burned up in the combustion chamber. Every car has some form of crankcase ventilation, also known as a PCV, CCV, oil separator, and a cyclonic separator. BMW CCV system are notoriously failure prone, leading to high oil consumption, burning oil, loss of power, misfiring, and high carbon deposits. The problems are worse on the turbocharged models where the CCV needs to keep up with the pressure from the turbocharger(s). An overhaul of the CCV system should be planned every couple of years and especially before the winter months. Signs of a failing CCV include: whistling noises in the intake, blueish smoke in the exhaust, high oil consumption, and thick white or yellow gunk under the oil cap.
	Appreciate 0 Quote