[E36graduate]

Intermittent low boost issues (JB3, BM DCI). Having same issues on all Map's and with JB3 turned off. Using the BM Tool, I have it set on setting 1 to watch the boost on my gas gauge. Empty = 0 and Full = 20 psi

Odd thing, car pulls hard (about 14 psi on gas gauge), but if I let the car come to an idle, sometimes the boost will be less than 1/2 way (9 - 10 psi), sometimes much lower.

If I'm starting out...sometimes the boost wont get about 5 psi?

I have found that If i let the RPM's come to an idle...it will either correct the low boost condition or the inverse (cause a low boost condition).

On the highway, the car is pulling strong and the boost gauge is working well....as long as I don't let the car come to an idle....sometimes.

I have NO codes. I had a low fuel pressure sensor code...just fixed today, code gone, condition of the low boost still exists.

Really strange....anyone got some ideas where to look?

[themyst]

Although BMS states they have addressed the boost reduction on newer 2.0 releases, the unit targets boost as a multiplier of the stock levels. If you monitor stock boost levels, you will see it will hit as much as 10psi in hot conditions, and as low as 6psi in cold conditions.

I can bet anything that your boost has dropped due to the fact the weather has gotten colder. Seeing that you're in MA, I am very certain this is the case. Bump a map up

[E36graduate]

Interesting....last night I did try Map 7 (I always run 93 octane) and then...tried Map 9 and Map 9 was running quite well, but I chose to turn it back down. It has been 40F and quite rainy all week.

I still don't understand, regardless of Map, why if I let the RPM's drop to Idle for a second or two, then the power is back???

[E36graduate]

Uh, thanks for the help guys! Talk about an idiot......I've had the JB3 Installed for about 3 days and I was assuming I was in a certain Map, however I don't think I was....

Here is how I assumed I was setting up the JB3 Map.....

1. Put the kefob in the thingy ( i tried pushing the start button but the car starts so I didn't push that button anymore).

2. Push gas pedal to floor for at least 4 seconds and then pump the gas the number of times for each Map.

It just dawned on me 30 minutes ago, as I was stressing all out and stuff, that If I didn't depress the clutch I could push the start button and all the lights and stuff came on and the car didnt start................wow.....newbie to E90!

Anyway....I also reset the BT tool (hold the button while plugging into ob2 port).

I went for a spirited drive and no more issues like before.

I have no clue what Map I was in prior to my brain fart...probably 15 or something really freaking bad, however the car is now driving sweeeeeetttttt!!! Pulling strong, minimal lag, 40F out, no rain...cool crisp air on Map 7 (93 octane, DCI)....

[Penn999]

Originally Posted by E36graduate

Uh, thanks for the help guys! Talk about an idiot......I've had the JB3 Installed for about 3 days and I was assuming I was in a certain Map, however I don't think I was....

Here is how I assumed I was setting up the JB3 Map.....

1. Put the kefob in the thingy ( i tried pushing the start button but the car starts so I didn't push that button anymore).

2. Push gas pedal to floor for at least 4 seconds and then pump the gas the number of times for each Map.

It just dawned on me 30 minutes ago, as I was stressing all out and stuff, that If I didn't depress the clutch I could push the start button and all the lights and stuff came on and the car didnt start................wow.....newbie to E90!

Anyway....I also reset the BT tool (hold the button while plugging into ob2 port).

I went for a spirited drive and no more issues like before.

I have no clue what Map I was in prior to my brain fart...probably 15 or something really freaking bad, however the car is now driving sweeeeeetttttt!!! Pulling strong, minimal lag, 40F out, no rain...cool crisp air on Map 7 (93 octane, DCI)....

With your mods I wouldnt be running anything over map 3, do you even have an upgraded chargepipe and dv's or a bov? I doubt your stock chargepipe would even hold over 13-15psi. Do a little more research on freeing up the airflow on both the intake side and the exhaust side. I bet your motor is experiencing quite a bit of heat, not to mention the turbos...I would look into that before you run map 7 much longer.

[E36graduate]

Oil is about 230F, never seen it higher, dual cone intakes, 40F ambient, 93 octane, Map 5 is considered acceptable by tuner, however Map 7 seems to work fine also? If it weren't as cool out, I would definitely go Map 5....not sure Map 3 is where I want to be but thanks anyways. Working on DP's and upgrading the DV here soon.....

[themyst]

Originally Posted by Penn999

With your mods I wouldnt be running anything over map 3, do you even have an upgraded chargepipe and dv's or a bov? I doubt your stock chargepipe would even hold over 13-15psi. Do a little more research on freeing up the airflow on both the intake side and the exhaust side. I bet your motor is experiencing quite a bit of heat, not to mention the turbos...I would look into that before you run map 7 much longer.

My stock charge pipe and dvs are holding close to 19 psi with no problems. I do agree you will be prone to heatsoak on map 7 on a sustained pull. I'd drop it down to map 5 on intake/tune/93 octane.

[themyst]

Originally Posted by E36graduate

Oil is about 230F, never seen it higher, dual cone intakes, 40F ambient, 93 octane, Map 5 is considered acceptable by tuner, however Map 7 seems to work fine also? If it weren't as cool out, I would definitely go Map 5....not sure Map 3 is where I want to be but thanks anyways. Working on DP's and upgrading the DV here soon.....

Log ignition timing with the bt cable on map 7. Bet it won't be pretty. I used to run map 7 on jb3/dci only and in this cold weather you can get away with it, but when it warms back up, dial it back down.

[Penn999]

Originally Posted by E36graduate

Oil is about 230F, never seen it higher, dual cone intakes, 40F ambient, 93 octane, Map 5 is considered acceptable by tuner, however Map 7 seems to work fine also? If it weren't as cool out, I would definitely go Map 5....not sure Map 3 is where I want to be but thanks anyways. Working on DP's and upgrading the DV here soon.....

Just so you know, outside temp doesnt matter if the inside of engine and your turbos are burning up due to the doubling the factory boost of our cars. But hey buy all means, do you what you think is right. haha, another thought about your outside temp theory...how do you expect to bring all of that cold air into your system if you dont have the proper tools to do so? I bet your EGT's are a good deal higher than what is considered a safe temp. Ask Mike@n54tuning and what he thinks, maybe its changed since he told me what to run 2 weeks ago...

[Mike@N54Tuning.com]

You know the CAN Tool boost isn't accurate with a piggyback system right?

Mike

[E36graduate]

Thanks Mike....I figured that out tonight...after I read the instructions and a few other instructions I overlooked....thanks for the heads up. The car is running great tonight.

[BrianMN]

Originally Posted by Penn999

With your mods I wouldnt be running anything over map 3, do you even have an upgraded chargepipe and dv's or a bov? I doubt your stock chargepipe would even hold over 13-15psi. Do a little more research on freeing up the airflow on both the intake side and the exhaust side. I bet your motor is experiencing quite a bit of heat, not to mention the turbos...I would look into that before you run map 7 much longer.

OEM DV's have no problem 'holding' high boost...they have problems reseating after shifting/relieving pressure. Not sure why you think he 'needs' that...Charge pipe/dv/bov's are the last thing you really "Need" to support high hp.

Originally Posted by Mike@N54Tuning.com

You know the CAN Tool boost isn't accurate with a piggyback system right?

Mike

It displays what the ecu thinks is boost, so 0-8/9 psi?

[Penn999]

[QUOTE=BrianMN;8315159]OEM DV's have no problem 'holding' high boost...they have problems reseating after shifting/relieving pressure. Not sure why you think he 'needs' that...Charge pipe/dv/bov's are the last thing you really "Need" to support high hp.QUOTE]

I believe in building a full system, from the ground up. If you feel like you want those shitty stock dv's on your car then so be it. But since I put my own aa bov on, I had to take apart that OEM chargepipe off. It was all junk plastic. IMO you should replace this rather soon on your list because what is the since in adding all of the boost w/o being able to reap all of the benefits....as you said, "reseating after shift/relieving pressure." BUT since the the uninformed OP seems to know what he was doing(running map 7 with no supporting mods)...It tells you straight up in the guide that you should be fully bolted before running map 7. (i.e....an upgraded chargepipe with either froge DV's or a BOV of choice.) I was trying to lend a little advice, and btw, did mike say it was cool to run map 7 with just a dci?