Boost Issue

[barrybrice]

2010 535i - I did a WOT test, DWP on the JB4 is set to 100 (Wastegate set st 100%) The start of the test is In 3rd gear at 60mph. When I floored it the boost dropped to 5 Hg then shot up to 20Hg and then settled at 15 Hg. Vacuum canister is at 22 Hg. Do I have a bad boost solenoid? Video is here:
https://youtu.be/pHCF6Tyr89g

[lisnowboarder]

Where are you measuring from? Positive pressure (boost) is in psi. Hg is vacuum pressure. Seems like you are measuring after a check valve.

How’s the car feel? I have a 2010 535xi and keep putting jb4 in a shopping cart but not checking out.


Sent from my iPhone using Tapatalk

[barrybrice]

I am measuring vacuum directly to the wastegate from the boost solenoid. In reference to the JB4 I am going to get rid of mine and go with the MHD to flash the car.

[pbonsalb]

I have runs jb4 on an 08 535xi and like it. I have not customized the tune and run the stock configuration in map 5 usually. Goes well in cold weather in the midrange and is faster than stock under any circumstances. A flash is better than a piggyback typically, so as much as I like the JB4, I’d be looking at the MHD if I was shopping now.

[lisnowboarder]

Well then its definitaly a bad JB4 and ill take it off your hands. But from what i understand through google you can convert you fuel gauge to a boost gauge with JB4. Why not do that and see what the car ECU is seeing?

- - - Updated - - -

I have runs jb4 on an 08 535xi and like it. I have not customized the tune and run the stock configuration in map 5 usually. Goes well in cold weather in the midrange and is faster than stock under any circumstances. A flash is better than a piggyback typically, so as much as I like the JB4, I’d be looking at the MHD if I was shopping now.

This may spin a tangent off the subject but from my research JB4 was a safer mod with failsafe's built in. At a high power level I see people using MHD backend with JB4 still to maintain the failsafe's.

[pbonsalb]

I would not say a JB4 on map 5 is high power. If you can get what you need from a MHD, just run that. I don’t know much about the MHD.

[lisnowboarder]

I would not say a JB4 on map 5 is high power. If you can get what you need from a MHD, just run that. I don’t know much about the MHD.

Correct. I was speaking towards 600+


Sent from my iPhone using Tapatalk