water in the cylinder

Question

2003 BMW 530i recent engine change has rough idle. A lot of water comes out of tail pipe engine does not have a head gasket problem did not over heat where is the water from my mechanic couldn't find it. Has anyone experience this

Answer 1

Water in the intake manifold, The only place it can come from is at the brake booster area, The drain at the brake booster can get plug and cause water to build up in that area,  What will happen is water will go into the intake manifold , thru the brake booster  this would cause rough idle and stumble the engine at acceleration. it would also set a fuel trim lean code.

​ Here is water present , this is where water will enter into the intake manifold by ways of vacuum in the brake booster

 The brake booster area should have a drain, and should be kept cleared of debris

​ To remove the water build up in the intake the throttle body would have to be removed

 With the throttle body removed , you can now easily remove the water that is in the intake manifold.​

​