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jamesmurray jamesmurray is offline
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Default 335i Boost problems - 05-27-2013, 06:46 AM

Hi guys, I've been a long time lurker, but have never posted until now!

Anyway I've noticed for a while now that my 335i is a little flat under part throttle, and occasionally there has been major lag when going WOT and revving it through the rpm's. I've replaced the vacuum hosing the runs from the vac pump to the vac capsules but this hasn't really improved things. It was much worse yesterday when I drove the car reasonably hard, as there was a large step in power, it was like the engine was straining, then it took off.

I decided today to follow Terry's video guide about testing the solenoids using a vac gauge a the JB4. At idle I was seeing 3-4in HG and when revved it went to about 13in HG. This was with future use D set to 99 as outlined in the video. From the results I'm thinking that I have a dead solenoid. Anybody else have any ideas?

My mods are; JB4 G4 Map 5, BMS OCC


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Russell @ BMS's Avatar
Russell @ BMS Russell @ BMS is offline
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Car: 2009 335i AT
Cool 05-27-2013, 10:23 AM

Test each solenoid separately by removing the Tee.
Does look like something is wrong.

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jamesmurray jamesmurray is offline
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Car: 335i
Default 05-27-2013, 12:14 PM

Thanks for the information. So would I plug the vacuum gauge into the output from the solenoid to the waste gate for each boost solenoid? What reading should I expect to see? Thanks

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