BMW Surging Idle – 2000 528i – 6-Cylinder M52TU – M54 and Others – Vacuum Leak – Intake Boot
This answer is applicable for many BMWs in addition to the one listed below.
car year: 2000
car model: 528i
Question; is there a boot that needs to be replaced to prevent engine from galloping during warm up?
If you mean that the engine is surging … or not keeping a steady speed during warm-up, this could be due to an intake system vacuum leak. This applies to all fuel injected BMW and MINI models. A very common source for a vacuum leak is the intake boot. Some models, such as your 2000 528i with the M52TU 6-cylinder engine, have two intake boots. Any cracks or rips in the boots, or any of the hoses that connect to the boots, can cause rough running and surging …. especially during the engine warm-up cycle. If you know that you have a leaking intake boot, let’s get that replaced first. Additionally, a full inspection of all of the intake and crankcase ventilation hoses would be in order. There can be no air leaks in any of these boots, bellows and hoses.
Additionally, have you checked to see if there are any stored engine management fault codes? If not, this should be done. We do offer a couple of options in fault code reading/reset tools.