[kolio]

I have an 07' 335 6MT with sports package, cat back exhaust, and proceed v1.

i was experieincing some issues with the car in any gear above 2nd. If you start hitting the throttle and try to build boost, it never really comes. WOT you can hear the turbos spool but it doesn't go. From the exhaust and the engine you can hear and feel surging. it does not pull steady. it's like some boost..... no boost..... some boost.... no boost

the car would not trigger the check engine light. Randomly driving it would throw it. and once in a while on cold startups.

i took it to my mechanic and we found 3 codes. the first 2 we believe come together. A code for something about ecu miscomunication and for cylinder 5 misfire. the last was a low boost pressure code.

Within the past 3 months i have had all the spark plugs replaced and all the coil packs.

cylinder 5 prob needs an injector. but what could be causing the low boost? we hooked up a smoker to the vacum lines and found no leaks or damaged lines.

any help?

thank you in advance

[rader1]

You should take a log with the PROcede.
Without more info its hard to say. Check your intercooler connections, charge pipe connections, DVs, and (especially) the vacuum lines.

[kolio]

Originally Posted by rader1

You should take a log with the PROcede.
Without more info its hard to say. Check your intercooler connections, charge pipe connections, DVs, and (especially) the vacuum lines.

i don't know how to log it. it was in the car when i bought it and it has a serial connector.

we checked the vacum lines with a smoke test and everything seemed fine

[djjasper]

Clutch slip?

[kolio]

Originally Posted by djjasper

Clutch slip?

i thought that, but why would it throw a code for low boost?

[rader1]

Remove the PROcede and see if it's tune related. In a situation like this, though, it's possible without the tune the problem is still there but the car just isn't pushed hard enough to show it

[J Boy]

Could be a million things...

try a boost leak test.

if that doesn't work, try disconnecting the battery for 30min and see if that helps

or possibly check your diverter valve

[JamesM3M5]

^ yes, you will have to do a boost pressure test of as much of the system as you can. Pull a vacuum on the wastegate actuators to see whether they move smoothly to a closed position. They start full open and the rod moves about 3/4" to shut the wastegates. They should be fully shut around 6inHg vacuum. I've seen them bind up and cause the wastegate to stick open - never builds boost.

[J Boy]

Originally Posted by JamesM3M5

^ yes, you will have to do a boost pressure test of as much of the system as you can. Pull a vacuum on the wastegate actuators to see whether they move smoothly to a closed position. They start full open and the rod moves about 3/4" to shut the wastegates. They should be fully shut around 6inHg vacuum. I've seen them bind up and cause the wastegate to stick open - never builds boost.

That would also make sense to why you hear it spooling but feel nothing.

At first glance I've seen two threads on the board both named wastgate rattle... seems like the wastegates on these cars are common to fail?

[kolio]

i guess we will have to try that or i'll bite it and take it to the dealer to have them figure it out. then back to my mech to actually fix it

[Wedge1967]

I'm having the same issue. 1st and 2nd I can get it to boost about 8 psi and if I go WOT the psi drops to 4. Car was in a wreck a few weeks back, hit a curb. Spoke with Shiv, and he thinks the waste gate is stuck open due to a bent actuator arm. Regardless, I can’t get the car to boost and it’s boosting enough to not throw codes. I have an open insurance case, I think I’m going to see if the shop can’t get the insurance company to agree to pay for the turbo replacement and I can use that many to buy a single turbo kit. RB’s are tempting, but now the kits are out I wouldn’t waste my time with upgraded twins.

Originally Posted by kolio

I have an 07' 335 6MT with sports package, cat back exhaust, and proceed v1.

i was experieincing some issues with the car in any gear above 2nd. If you start hitting the throttle and try to build boost, it never really comes. WOT you can hear the turbos spool but it doesn't go. From the exhaust and the engine you can hear and feel surging. it does not pull steady. it's like some boost..... no boost..... some boost.... no boost

the car would not trigger the check engine light. Randomly driving it would throw it. and once in a while on cold startups.

i took it to my mechanic and we found 3 codes. the first 2 we believe come together. A code for something about ecu miscomunication and for cylinder 5 misfire. the last was a low boost pressure code.

Within the past 3 months i have had all the spark plugs replaced and all the coil packs.

cylinder 5 prob needs an injector. but what could be causing the low boost? we hooked up a smoker to the vacum lines and found no leaks or damaged lines.

any help?

thank you in advance