740il not running properly
Hi, i'm new here but i've been referring to this forum for various helpful topics so I wanted to ask you guys your thoughts and get some help and feedback on my issue.
Ok, I own a BMW E38 740il of 1995. Recently, the car was vibrating as if one of the pistons weren't working properly.
Brought my car to the mechanic and had them check it up on the computer, but it showed there were no problems or errors.
They told me to put in the STP fuel injector cleaner.
The car hardly made 1 km after minutes of putting the cleaner in!
Managed to get the car back to the mechanic.
At this point, when the car is cold, it starts up, but not with all 8cyl...
When the car is warm, it takes a while before we can get it started up, but still, not all 8 cyl. are working!
After a few min, the car dies.
Now the computer shows there is an increased air intake.
I had them empty the tanks from the STP and cleaned everything before refilling it with 10liters of petrol.
Retried starting it, nothing changed.
The mechanics also changed all spark plugs, MAF, air filter, fuel filter, clean injectors, measured piston pressure, and the fuel pressure was measured.
Retried again, nothing changed.
Since the 4 cyl. on the left side of the block were clean and still run properly, they thought of inverting the oxygen sensor in the exhaust because 3 out of 4 cyl. on the right side of the block were somewhat dirty.
Spent my weekend trying to find and answer online before they tow it to the BMW shop tomorrow.
Can anyone give me some advice or thoughts on such?
Last edited by 7BMW; 07-22-2012 at 12:43 PM.