I've noticed my BMW 535xi 08 shaking on acceleration usually around 1500-2000 rpm. I changed the coils because I had a cylinder 3 misfire which took care of that problem but the shaking shuddering is still there. It is pretty preodominat when going up hills it's shaking a lot. I was thinking it might be the high fuel pressure pump any suggestions anyone? Thanks in advance

 

It can be anything. Is there a code? Did you check the coils?

 

yes the coils were replaced, no codes, it only occurs at around 2000 rpm and then goes away

 

Did you have any codes? Did you double check the coils to ensure they are properly connected. If not connected properly it could cause that shake. Did you notice any oil around cyl 3, cyl 3 sits below the engine oil fill hole so if you added oil recently that could have tripped the cyl 3 misfire and left oil around there, and causing the existing shake.


without codes it is real tough to know where to start.

 

The only codes I had was cylinder 3 misfire and system too lean bank 1 but now no more codes after I deleted them after I installed the new coils

 

The only thing I can tell you is to wait for a code to pop up. You do not want to just through parts at it hoping it is right.

 

Ok I just got a code P0171 system too lean bank 1

 

Check for air leaks and clean your MAF. How many miles do you have on it? Di you change all the coils and plugs. My next step will be seeing if you either have a bad injector or O2 sensor. Im leaning towards O2 or vacuum leak

 

My car is in shop as I type this for the P0171. My valve cover cracked and threw the lean code. That could cause the misfire so my suggestion is to get a smoke test to see if there is a leak.

 

I actually have a smoke tester do I smoke it through the intake/maf sensor side? Or through a vacuum line