[adisw]

Hi Everyone,

I've had a brand new JB4 installed on my '08 N54 car for about 6 months now. My car typically sits on Map 2 or 3. When I get into the high RPM's / boost levels at WOT, I get two blinks from the turn signals telling me that the JB4 detected an issue and moved me into Map 4. This issue is consistently repeatable.

The car has no codes, a JB4 installed with an MHD backend, DCI, blow of valve, VRSF charge pipe (doesn't fit that well on the manifold), and DPs. I run straight 91 here in California.

I've been scratching my head for a while on this, and finally got around to getting some logs collected from the JB4. I'm not an expert in interpreting them, but maybe this will help in diagnosing the issue?

Any ideas on what the problem could be? Thanks ahead for the help.

[Saif2018]

Originally Posted by adisw

Hi Everyone,

I've had a brand new JB4 installed on my '08 N54 car for about 6 months now. My car typically sits on Map 2 or 3. When I get into the high RPM's / boost levels at WOT, I get two blinks from the turn signals telling me that the JB4 detected an issue and moved me into Map 4. This issue is consistently repeatable.

The car has no codes, a JB4 installed with an MHD backend, DCI, blow of valve, VRSF charge pipe (doesn't fit that well on the manifold), and DPs. I run straight 91 here in California.

I've been scratching my head for a while on this, and finally got around to getting some logs collected from the JB4. I'm not an expert in interpreting them, but maybe this will help in diagnosing the issue?

Any ideas on what the problem could be? Thanks ahead for the help.

Probably a better idea to post this on N54tech forum as that's more JB4 oriented

[bimmerguy1210]

When the hazards flash twice, that means that you are running lean. This is usually inidicative of a failing hpfp, injectors, or lpfp. The log provided is not very good, but it does appear your AFR's are a bit lean. Take a better log so we can better analyze the parameters of your hpfp and injectors although they do seem OK from the log.

Provide a better log but in the meantime, do yourself a HUGE favor and flash the BMS backend flash through MHD now. Do it now, after you read this post (or get rid of the jb4 and flash MHD). This will improve AFR's greatly. You can do the PUMP flash which will be good for 91ACN and up to E30. If you have access to E85, add a few gallons as it will help with timing corrections and keeps combustion at cooler temps since it increases your octane. One last thing to note, Map 2 should be used for 93 octance, so maybe that's causing some issues. You should be in Map 5 or Map 1 to be safe.