[exidisjon]

I been throwing half engine limp mode these days and it often happens after 1hr or more driving and during steady crusing and than giving it a bit gas at around 2.5k~3k rpm in 4th. Car is running strong and has no problems. Fuel pump was just replaced and car runs strong. I can not replicate the limp mode driving stock. After i put the JB3 or JB+ back on the car it runs fine until i get the same limp modes once a while.
I scanned with the bt scanner and it threw a 30ff turbo pressure to low code.
I read thru searching that this is a possible leak problem. I asked the dealer recently after deleteing the codes and they found nothing wrong.
I installed the tune again and i throw this limp mode once every often.
What can be the problem?
Does this code have anything to do with tune protection? Is it smart to bring the car WITHOUT deleteing the 30ff code so they try to find the problem more? What can i do to find out why im throwing the limp.
BT scan shows its throwing limps at 4th gear during 2800 rpm.

Any input would be nice.
Thanks.

[Panoz]

the "key"-question is "what mods you have"

The leak could becomming mainly from FMIC, aftermarket Divert valves or Intake housing pipes.

[ThorsHammer]

Likely the Charge Pipe...either where it meets the FMIC or the Throttle Body.

It's definitely a leak. I got this code when my Charge Pipe literally blew off the Throttle Body.

Do you have an Oil Catch Can? If not, oil gets into the Charge Pipe and it could be enough to loosen the seal at the FMIC or the Throttle Body. It's definitely something to check out.

I would start with popping the CP off on the TB side (it's easy...just pull up on the metal clip/handle-looking thing) and slide it off. Check it for oil, clean it with a microfiber rag, and put it back on. Then I'd check the connection at the CP and the FMIC...same thing. Finally, check the connection on the FMIC itself.

The only other place could be a vacuum leak or boost leak on your Diverter Valves. Tell us all your mods, and that will make it easier.

But to answer your main question, yes, it's okay to leave that code, remove your mods/tune, and take it to the dealer. But you can't take it in with an after-market FMIC or Diverter Valves, let alone a tune. The code itself is not indicative of a tune or mod.

Hope that helps.

[gt3fever]

Originally Posted by ThorsHammer

Likely the Charge Pipe...either where it meets the FMIC or the Throttle Body.

It's definitely a leak. I got this code when my Charge Pipe literally blew off the Throttle Body.

Do you have an Oil Catch Can? If not, oil gets into the Charge Pipe and it could be enough to loosen the seal at the FMIC or the Throttle Body. It's definitely something to check out.

I would start with popping the CP off on the TB side (it's easy...just pull up on the metal clip/handle-looking thing) and slide it off. Check it for oil, clean it with a microfiber rag, and put it back on. Then I'd check the connection at the CP and the FMIC...same thing. Finally, check the connection on the FMIC itself.

The only other place could be a vacuum leak or boost leak on your Diverter Valves. Tell us all your mods, and that will make it easier.

But to answer your main question, yes, it's okay to leave that code, remove your mods/tune, and take it to the dealer. But you can't take it in with an after-market FMIC or Diverter Valves, let alone a tune. The code itself is not indicative of a tune or mod.

Hope that helps.

good info

i experienced same issue after had IC installed. will look more into it

[exidisjon]

Only mods i have is a DCI and a tune. THe limp mode occurs alot more at same throttle respond at around 2800 rpm at 4th gear only. Happens every day few times after long drive with JB+ and happens once a while with JB3. Can never replicate it without a tune... So i think it has something to do with the lowend boost spike maybe? This is driving me crazy..

[turb0]

Originally Posted by exidisjon

Only mods i have is a DCI and a tune. THe limp mode occurs alot more at same throttle respond at around 2800 rpm at 4th gear only. Happens every day few times after long drive with JB+ and happens once a while with JB3. Can never replicate it without a tune... So i think it has something to do with the lowend boost spike maybe? This is driving me crazy..

I threw that code (and others) when I had a boost leak from the diverter valves but it occured stock and with a tune and at any gear/rpm (usually right when I hit boost). I would think a leak would cause the car too limp instantly unless it was really small.

This might be totally unrelated and I don't know what code it would actuallt throw but maybe ur settings o jb+ or map on jb3 is too high for ur mods/temp/gas. I say this cuz last time i got a limp was around 4th gear on map 7 in like 85degree weather

[Alpina_B3_Lux]

Originally Posted by turb0

I threw that code (and others) when I had a boost leak from the diverter valves but it occured stock and with a tune and at any gear/rpm (usually right when I hit boost). I would think a leak would cause the car too limp instantly unless it was really small.

I have exactly the same problem - half engine light every so often when I hit the throttle, also in more or less every gear. Interestingly however it does not occur systematically - sometimes I push the car really hard and nothing happens, at other times I just step very little on the throttle in 2nd or 3rd gear and it throws the half engine light.

My flash tuner (Evotech) first told me this is often due to the stock air filter (it being too dirty), but after having replaced that with a brand new drop-in from BMC I have excluded that explanation. I also think it's a minor boost leak somewhere, and my guess is that it's somewhere at the diverter valves (I got the Forge ones) or the FMIC where some screws have to be tightened. I'll have it checked out when I'll have my oil cooler installed at the end of the month.

BTW, someone posted a DIY for a pressure test a short time ago. That could also be useful in this context.

Alpina_B3_Lux

[kiteboy]

Originally Posted by Alpina_B3_Lux

I have exactly the same problem - half engine light every so often when I hit the throttle, also in more or less every gear. Interestingly however it does not occur systematically - sometimes I push the car really hard and nothing happens, at other times I just step very little on the throttle in 2nd or 3rd gear and it throws the half engine light.

My flash tuner (Evotech) first told me this is often due to the stock air filter (it being too dirty), but after having replaced that with a brand new drop-in from BMC I have excluded that explanation. I also think it's a minor boost leak somewhere, and my guess is that it's somewhere at the diverter valves (I got the Forge ones) or the FMIC where some screws have to be tightened. I'll have it checked out when I'll have my oil cooler installed at the end of the month.

BTW, someone posted a DIY for a pressure test a short time ago. That could also be useful in this context.

Alpina_B3_Lux

hello i've got also this fault code, in same condition like you.

F3100 & F30FF , so what is the issue to solve it ?

[kiteboy]

Originally Posted by ThorsHammer

Likely the Charge Pipe...either where it meets the FMIC or the Throttle Body.

It's definitely a leak. I got this code when my Charge Pipe literally blew off the Throttle Body.
Do you have an Oil Catch Can? If not, oil gets into the Charge Pipe and it could be enough to loosen the seal at the FMIC or the Throttle Body. It's definitely something to check out.

I would start with popping the CP off on the TB side (it's easy...just pull up on the metal clip/handle-looking thing) and slide it off. Check it for oil, clean it with a microfiber rag, and put it back on. Then I'd check the connection at the CP and the FMIC...same thing. Finally, check the connection on the FMIC itself.

The only other place could be a vacuum leak or boost leak on your Diverter Valves. Tell us all your mods, and that will make it easier.

But to answer your main question, yes, it's okay to leave that code, remove your mods/tune, and take it to the dealer. But you can't take it in with an after-market FMIC or Diverter Valves, let alone a tune. The code itself is not indicative of a tune or mod.

Hope that helps.

what do you mean like this i'm french i don't understand ??

what is FMIC ????

[Elie335]

Originally Posted by kiteboy

what do you mean like this i'm french i don't understand ??

what is FMIC ????

the charge pipe attached to the intake manifold popped out due to the high boost input.

FMIC = front mount intercooler

[kiteboy]

Originally Posted by Elie335

the charge pipe attached to the intake manifold popped out due to the high boost input.

FMIC = front mount intercooler

is on the front mount intercooler, there is a manifoild with connector which is responsible to measur boost pression ?

have you picture or photo to locate this ?

[TLO03]

I was just looking at this stuff.. Here

http://www.realoem.com/bmw/showparts...85&hg=13&fg=20

[Elie335]

Originally Posted by kiteboy

is on the front mount intercooler, there is a manifoild with connector which is responsible to measur boost pression ?

have you picture or photo to locate this ?

I'm trying to understand, but its not necessary always to have the boost leak from the charge pipe, it can be from the intercooler pipes as well...

[kiteboy]

ok but how it's possible to have no problem, when sportively driving ?

pb appear when low RPM in 5th or 6th gear around 2800 rpm maybe.....

and connector that you mean is number 6 on scheme ???

[Elie335]

Originally Posted by kiteboy

ok but how it's possible to have no problem, when sportively driving ?

pb appear when low RPM in 5th or 6th gear around 2800 rpm maybe.....

and connector that you mean is number 6 on scheme ???

that's the sensor, it doesn't have anything to do with it, check every hose if its popped out or it is leaking in that figure on your car....

[kiteboy]

Originally Posted by Elie335

that's the sensor, it doesn't have anything to do with it, check every hose if its popped out or it is leaking in that figure on your car....

i ve just read this http://www .e90post.com/forums/showthread.php?t=38856

if it could due to a blow off ??

i think if it was connection hose or other, it will done problem when hard driving and sport driving no ?

[007_e350]

Originally Posted by kiteboy

i ve just read this http://www .e90post.com/forums/showthread.php?t=38856

if it could due to a blow off ??

i think if it was connection hose or other, it will done problem when hard driving and sport driving no ?

If it was that obvious you'd see 30ff all the time. It's something minor that leaks when fully hot. Im doing this today let's see what I find

[dreadnaxt]

any updates? having the same issue. the hotter the temperature outside, the easier it's to get 30ff. accelerating in 4-6th gear from 1.5k rpm and at around 2.5-3k rpm i get the limp light.
so far i changed all the vacuum hoses, DVs and solenoids. so it looks like it's really leacking somewhere. another idea i had was that the boost sensor is giving wrong data, but i checked and it looks fine

[kiteboy]

Fmic leak ? Have you check this

[007_e350]

Originally Posted by 007_e350

If it was that obvious you'd see 30ff all the time. It's something minor that leaks when fully hot. Im doing this today let's see what I find

Sorry I forgot to update, I found the following:

1- Charge pipe was missing the arm bolt, I'd imagine engine moves a bit that caused the pipe under boost pressure to release some

2- Found minor leak on the FMIC cold side connector, cleaned reconnected - also linked to above

3- rear turbo intake not properly connected, this wont cause boost leak but it bothers me (dirty air goes in), took out downpipes and put a clamp on there.

4- Diverter valve was hissing under pressure, replaced with a new one for $60

everything put together, car runs great no codes, hope it helps

[dreadnaxt]

Originally Posted by kiteboy

Fmic leak ? Have you check this

Not yet. Gonna check tomorrow.