Intermediary Arms 4.8is

[4.8isguy]

Hey Guys. I've been getting a bit of a rough idle on the 4.8 lately. Its on cold start only but it lasts for a good 15-20 min. Indy says its the Intermediary Arm which is a very involving job that involves taking apart the head. I've already done the entire cooling system on the car minus the Coolant Transfer Pipe which is what I currently have the car in the shop for. Thats a 2k job on its own. I got a good deal on the car so I don't mind spending a little money but I still wan't to do transmission fluid/programming along with front left axle. I was hoping on keeping this car for at least a good 5 years. Any recommendations. I'm debating whether I should just move on from this one and try and find either a lower miles one or one that has all the maintenance already done to it. I do love the car but I don't want to fund a potential money pit.

[TiAgX5]

What is the mileage? I think you are referring to the intermittent shaft levers.

[bcredliner]

Could be the intermediate arms but could also be other causes. Has Indy done the basic troubleshooting such checking MAF or pressurized smoke test for vacuum leaks? Do you know what fault codes are showing?

[A B Able Truck]

Related information;

http://www.bimmerfest.com/forums/att...8&d=1279113064

.: Search results for exhaust smoke

[4.8isguy]

Car is currently at 88k miles. Have not had any error messages since purchased car.

[TiAgX5]

Originally Posted by musov5

Car is currently at 88k miles. Have not had any error messages since purchased car.

Was a service history provided with the vehicle that shows all oil changes were done with a BMW approved oil?

Some owners "cheap out" by going to Iffy Lube for changes, get non-long life and/or higher weight oil, and sometimes NO filter change, then drive until the Service Interval Indicator indicates it's time to change it again. This results in excessive wear.

[bcredliner]

At 88,000 miles, and no blue smoke out the back, I would want to know how long the O2 sensors have been in place. If you don't know or they are original I would check or replace pre cat sensors. That could be the cause of cold rough idle. O2 sensors don't cause a fault but it does usually show as a lean condition. When you say it is not showing any error messages, is that from using BMW diagnostic equipment?

[4.8isguy]

Mechanic hooked up his computer equipment and said there are no faults present relating to that. My guess would be 02 sensors are probably original. I recently did the spark plugs and sockets. I also did the cooling system minus the coolant pipe which I just got replaced with the expanding coolant pipe. Right now I'm looking at about 6k in the whole on maintenance which I don't mind as long as the car gives me a few solid years out of it.

[bcredliner]

Has a smoke pressure test been done to check for vacuum leaks?

Did the mechanic find any faults at all?