Half full engine light. Engine malfunction reduced power

[jadidaskv]

So just got a 08 535xi at and auction with 167k for $4500. On the test drive there it drove great. Picked it up today, got gas about 3miles away, went to autozone for oil because the idrive showed it was really low so wanted to put oil in to get it home. Putting one qrt at a time with no change on the idrive even after 4 qrts. The oil service light wouldnt reset and still wouldnt go up on the idrive. Driving great the whole time, 10-15miles, getting on the highway n getting on it the half full engine light came on with the engine malfunction on the idrive. Couldnt feel the turbos kick on n fell on its face at 3k rpms n wouldnt go over that. Hooked up my bluetooth scanner couldnt get a code. The regular CEL light wasnt coming on, hooked up my buddies bluepoint scanner and an evap small leak detected code came on, eventhough the cel never came on. Cleared it n it came back. Found one of the vacuum likes to the reservoirs that go to the turbos disconnected, plugged it in, turbos kickin on, driving great, half full engine light, engine malfunction, reduced power came on again, still not throwing any codes other than the small evap leak.

Have until tomorrow to figure it out and bring it back because the auction will take it back if it has engine or transmission problems. Getting that half full engine light but no codes. Id really like to figure out whats wrong with it and fix it cause the cars great otherwise, but dont want to get stuck with something with a very costly repair. I can do all the work myself, even ordered cables n the latest bmw software for it but wont be here for a few days and dont have that kind of time. I dont see why even the bluepoint scanner is only picking up evap code but nothing for the engine malfunction reduced power. Being a holiday dealers or anywhere with bmw software isn't open.

[jadidaskv]

When its in park and i give it gas it revs right up no problem at all, half full engine light only comes on when it's in gear and floor it. Seems to be idling fine, doesnt seem to be misfiring or studdering, everything seems to be fine except the reduced power light comes on when WOT. After plugging in the vacuum line to the turbo reservoirs the turbos come on and revs right up now. Weird the regular CEL doesnt come on, and weird i get no codes but that engine malfunction reduced power light is off everytime i start the car, everything is fine until WOT then it comes on. The line the was disconnected is on the bottom of the left reservoir. I would think one turbo would have still worked if it was only one reservoir that was disconnected, or maybe now that thats connected thats the only turbo thats working and the other one is bad? Thing takes off like a rocket after connecting that line but the damn light still comes on. Really wish it would give me a code so i had an idea where to look. Maybe just a software update is needed?

[jadidaskv]

So ended up takin the gamble and keeping the car because everything is so nice with it and the turbos are working, no waste gate rattle, and drives real good until punch it/WOT. Did an oil change, was 4qrts over because the level sensor isnt working. It started misfiring the night before the oil change, did the plugs on it, and replaced the air filter. Put about 20miles on it and no CEL, no mksfire, punched it a few times and the engine malfunction reduced power light hasnt come back on. Seems to be doing real good. All it seems to need now is valve cover gasket and oil cooler gasket, tensioner, tires, and the oil levell sensor. Feel like got a good buy, as long as that engine malfunction light doesnt come back on i feel good about it. If it does im scared lol.

[chowderdamenace]

Looking into getting an 08 535i and I got the half full light with no turbos while entering the freeway. Did the light ever come back on for you?

[Reefin' Dude]

best to pull the codes, but with that many miles i expect that the waste gates are bad. 30ff error. underboost error.

G~