BMW 335D and X5 35D - Diagnostic Questions
Cheap Diagnostics Before Throwing Parts at a Car
- Have you checked for vacuum leaks with a mityvac?
- Do you have any CEL codes?
- What scan tool are you using?
- Have you replaced or swapped your vacuum converters?
- Have you tried driving with your MAF unplugged?
- Have you tried pressure testing the boost plumbing and intercooler system?
- Has your car had CBU cleaning done lately or inspection to see if you have CBU?
- Have you checked the vacuum to the large turbo actuator by the firewall while idling and driving?
- Have you checked your MAP sensor for CBU?
- Check vacuum to the large turbo actuator while it's idling and while driving.
- Use a mityvac to actuate the large turbo actuator, make sure it works properly.
Throwing Parts at a Car
- Replace all vacuum lines
- Block off EGR cooler and delete it's vacuum actuator.
- Install a new vacuum converter by the firewall, if that doesn't improve things, swap it to the front one or replace both
- Replace your MAF
- Replace your MAP sensor
- Consider CBU cleaning