remuse

Hi All,

My '04 545i with 23,840 miles still idles rough when it is idling in Park and Drive. It does not matter whether the car is cold or hot. However, when the air condition is on, the rough idle is not as apparent.

My problem started back in early May' 06 and as of yet the rough idle problem still have not been resolved after going to 2 BMW dealership.

Here is the link to my first post back on May 13:
http://forums.e60.net/index.php?show...;hl=rough+idle

Where it stands right now with my first dealer is that they are saying my fuel has too much ethanol hence causing the poor idle quality. They came to this conclusion, after my check fuel cap light came one. After two fuel tests were conducted, they determined I had about 20% ethanol as opposed to the allowable 10% ethanol. As a side note, the first fuel test I had pumped Shell 91 Octane and the second fuel test I had pumped Chevron 91 Octane. The dealer also tested their loaner car and it had about 18% ethanol.

After going to my first dealership without much significant improvement even though they did all those work listed in the above link, I went to a second dealer and they couldn't fix the rough idle problem either. Both advised me it is an inherent characteristic with the 545i and that it is "normal".

The second dealership adjusted the valve lift from .7mm to .3mm which helped the rough idle. However, you can still feel the rough idle when the car is idling in Park or Drive. When the air condition is on, the idle quality improves significantly.

The report from the second dealer is as follows:
"Vehicle was hook up to GT1 check rough running values 1-8 cylinders on all values were within specs of BMW normal for engine to idle higher with A/C on , normal with A/C off normal for this idle with this engine.


As of right now, I was informed by my first dealer to wait for the fuel additive which supposedly is coming out in mid September.

I don't even drive my 545i as much due to the poor idle quality when it is in idling in Park and Drive.

What do you guys suggest at this point? Am I suppose to drive the car with A/C on even in winter time? Does any other 545i owners encounter this rough idle in Drive or Park as well as?

Thanks in advance and sorry for the long post.

EBMCS03

Wow Yikes... still having the problem?

Just a off the wall thought... When or have you added any oil to your engine? When was your last oil change?

Possibly April 06? May 06?

But then again if they tested and adjusted the valve lift would the engine oil need to be drained for that?

I'm just thinking it might have been over filled with oil and thats causing the roughness... again off the wall thought since you dont seem to be having any luck with the dealers...

znod

I can't help except to say that a rough idle is not a characteristic of my 545i.

Hormazd

There is a recall on the 545 for part on the induction system that causes noticeable rough idle. See your dealer.

cobradav

Are u kningly putting ethanol "enhanced" gas in your car or is it unmarked and it "might" be. BMW does have a bulletin out saying they do not recommend more than 10% ethanol

SI B 13 01 06
Fuel System & Control March 2006
Technical Service

SUBJECT
Alcohol Fuel Blends in BMW Vehicles


MODEL
All with gasoline engines


SITUATION
Fuel blends containing a high percentage (above 10%) of alcohol, mainly ethanol, are becoming more commercially available. Customers inquire about the possibility of using alcohol fuels (e.g. E85) in BMW vehicles.

INFORMATION
Fuels containing up to and including 10% of ethanol or other oxygenates with up to 2.8% oxygen by weight, that is, 15% MTBE (methyl tertiary butyl ether) or 3% methanol plus an equivalent amount of co-solvent, will not void the applicable warranties with respect to defects in materials or workmanship.

Although, usage of such alcohol fuel blends may result in drivability, starting, and stalling problems due to reduced volatility and lower energy content of the fuel. Those drivability problems may be especially evident under certain environmental conditions, such as: high or low ambient temperatures and high altitude.

Only specially adapted vehicles (FFV - Flexible Fuel Vehicles) can run on high alcohol fuel blends. BMW, for the various technical and environmental reasons explained below, does not offer FFV models.

Usage of E85, or any other high alcohol content blend (e.g. E30) in BMW vehicles, will cause various drivability complaints (cold start problems, stalling, reduced performance, poor fuel economy, etc.), may cause excessive emissions, and may cause irreversible damage to engine, emission control and fuel delivery systems due to incompatibility of materials with alcohols.

General Notes Regarding E85 Fuel.

E85 fuel contains 85% (by volume) of ethanol and 15% of gasoline. Ethanol can be produced chemically from ethylene or biologically from grains, agricultural wastes, or any organic material containing starch or sugar. In the US, ethanol is mainly produced from corn and is classified as a renewable fuel.

Similar to gasoline, ethanol contains hydrogen and carbon; with additional oxygen molecules build into its chemical chain. This chemical structure makes ethanol's burning process slightly cleaner compared to the gasoline (lower tailpipe emissions).

On the other hand, due to lower carbon content, ethanol provides 27% less energy (for identical volume) then gasoline, resulting in the reduced fuel economy of E85 vehicles (approximately 22% higher consumption). Increased fuel consumption requires the appropriately enlarged fuel tank capacities (usually 30% increase), and the specific DME calibrations for the E85 lower Stoichiometric air/fuel ratio (10 compared to 14.7 for gasoline engines).

E85 fuel volatility is typically lower then gasoline (RVP 6-10 psi, compared to 8-15 psi for gasoline). Lower fuel volatility will reduce vehicle evaporative emissions, but it may cause cold starting problems especially with lower ambient temperatures.

Under certain environmental conditions, mainly lower ambient temperatures, ethanol separates from gasoline/alcohol mixture and absorbs water. The ethanol absorbed water molecules are heavier then gasoline or ethanol, they remain at the bottom of fuel tank and when introduced into combustion process they tend to form an extremely lean mixture resulting in misfire, rough idle and cold starting problems.

Certain materials, commonly used with gasoline are totally incompatible with alcohols. When these materials come in contact with ethanol, they may dissolve in the fuel, which may damage engine components and may result in poor vehicle drivability.

Some metals (e.g. zinc, brass, lead, aluminum) become degraded by long exposure to ethanol fuel blends. Also, some nonmetallic materials used in automotive industry such as: natural rubber, polyurethane, cork gasket material, leather, polyvinyl chloride (PVC), polyamides, methyl-methacrylate plastics, and certain thermo & thermoset plastics degrade when in contact with fuel ethanol.

In order to safely and effectively operate a motor vehicle running on E85, the vehicle must be compatible with alcohol use. Some manufacturers have developed vehicles called FFV (Flexible Fuel Vehicle) that can operate on any blend of ethanol and gasoline (from 0% ethanol and 100% gasoline, up to 85% ethanol and 15% gasoline). Ethanol FFVs are similar to gasoline vehicles, with main differences in materials used in fuel management and delivery systems, and DME control module calibrations. In some cases, also E85 vehicles require special lubricating oils.

Aftermarket conversions of gasoline-powered vehicles to ethanol-fueled vehicles, although possible, are not recommended due to internal materials and DME software incompatibility, as well, as the high costs of conversion.

WARRANTY INFORMATION
Components damage/malfunctions, or any drivability problems caused by use of fuels containing more then 10% ethanol (or other oxygenates with more then 2.8% oxygen by weight) will not be covered under BMW warranties with respect to defects in materials or workmanship.

DR.Z

I just had this recall done on my '04 545.
My idle was allways smooth but some mornings that V8 would bounce RPM a bit, nothing that I would complain about.

Since the recall my idle has been ROCK solid , a hair under 500 RPM, I have had to rev the engine to make sure it was still running.

The recall is free and worth the 20 minutes it took to install.

DR.Z

dba1t

I have the same issue. Do any of you have the recall number?

CVTBenhogan

I can't help except to say that a rough idle is a charateristic of my 550i.

Does it get smoother after warmup??

remuse

CVTBenhogan: Unfortunately, it does not get smoother after warmup.

remuse

Thanks Dr. Z!