Please help! 540i dying big time!
Been looking on here for a looonngg time but not a frequent poster on many forums these days. Happy to be here though now.
Soooo my 2002 540i auto keeps dying. The last few weeks the car seems to have felt "heavy" and almost jerky at times relating to throttle response (and tranny was shifting kinda oddly at some points but idk if its related). A few days ago went outside to go grab a bite to eat with the girlfriend and the car would not unlock with the key fob. messed around with the keys for a few minutes and it finally unlocked. (I had been getting the coolant low message once ina bit if that even matters, but i think that might be an expansion tank however i want to divulge everything.)
THEN, I start my car and am just out of my work parking lot and the car studdered a bit then the engine failsafe program mesage displays on the dash. Car drove home and ran almost better than normal (more responsive).
Let the car sit overnight and it started, still has same message display. Unhooked the battery for an hour, hooked it back up then started with no message. It ran for a few minutes and thought all was good. (i also topped off a tiny a bit of oil)
About 1/4 mile after i left my house the car died without any warning. Turned it off after coasting into a parking lot then started right up like no problem. Then on my way home, died again. The car on the last run home was seeming to want to die at lower RPM.
I replaced the battery thinking it might be a voltage issue (and it was the original at 11 years old.) Started and ran well then started the idle issue again.
Started the car and it started wayyy easier quicker and less cranking), ran fine for 2 mins then shut off. Same thing 3 times in a row. Finally the fourth time i gave it a bit of a rev and the car ran fine idling for about 10 minutes. No lights anymore but it never had one when it cut off these 3 times either.
I then cleaned the MAF (only sprayed with MAF cleaner not touching parts with Q-tips), which really wasnt all that dirty but did so and put in a new air filter. The car ran really well for about a day and a half like it was fixed. The car started to lose power when i hit the pedal like it wasnt registering until it would go to a pretty open position and then died again. Had to have it towed home.
So i had the codes read from a Snap-On scanner:
CODE 85 - Secondary Air Valve Circuit
CODE 115 - Hot Film Mass Air Sensor
This lead me to believe the MAF was bad, so i purchased a new BOSCH unit. Waited the few days and installed it yesterday. The car started up and was running much better it seemed while still cold however it was blowing a good bit of smoke from the exhaust. I hadn't ever had a problem with this before so that was odd. Seemed to run ok but was smoking from the exhaust. I thought maybe just because it sat for a few days motionless. Well the car started to run rough and idle unsteadily, then rough. Then I revved the car to see what that might do as a test of the higher RPM and all, and then it dies. Turn it back on and right away i get "!Stop Engine! Check oil something (i believe oil pressure)" from the display. Checked oil level from dipstick and its between the two marks.
Re-Started the car about 2 hours later. It started and ran fine (no smoke or oil pressure warning) but i heard this sound almost sounded like a sucking sound of something closing and then the car idled down like its warmer/in closed loop. This sound is the sound i heard everytime when teh car was dying in the very beginning! It then started idling up and down and also pretty rough and i turned the car off. Whatever this is seems to be at operating or semi warmer temps at this point.
I got it home and am driving the lexus but NEED the BMW running as i have a trip i need it to work for.
So does anyone have ANY freaking idea what is up with the car???