Mercedes-Benz GLA Forum banner
1 - 7 of 7 Posts

·
Registered
Joined
·
2 Posts
Discussion Starter · #1 ·
I have an electric actuated TurboSmart dual port BOv/BPV. It opens under acceleration after the car warms up. Will not happen if not in gear. The car needs a load on the engine I guess. It happens somewhat intermittently. I have a renntech tune and had this combo for quite some time before it began. The last update I did to the car was an Alpha main core heat exchanger. This was a month or so before the issue however.
Any ideas?
Already had a shop replace the boost pressure sensor after Check Engine light came on.
 

·
Premium Member
Joined
·
351 Posts
there are a slew of params, oem/am interfaces etc

1 thing that may not be feild tested much, what is the spring pressure on that TS BPV ?

You may be finding out.
If youre running a load based tune, and the air density is lower from ambient heat, the commanded MAP will be higher
 

·
Registered
Joined
·
2 Posts
Discussion Starter · #3 ·
there are a slew of params, oem/am interfaces etc

1 thing that may not be feild tested much, what is the spring pressure on that TS BPV ?

You may be finding out.
If youre running a load based tune, and the air density is lower from ambient heat, the commanded MAP will be higher
Thanks for that. This is the first idea that isn’t just a random guess. What would be solution? Spring or Tune. It did however happened when I went back to OEM tune. It just took a few days and then began recreating itself again.
 

·
Premium Member
Joined
·
351 Posts
Thanks for that. This is the first idea that isn’t just a random guess. What would be solution? Spring or Tune. It did however happened when I went back to OEM tune. It just took a few days and then began recreating itself again.
Thats an interesting data point.

dunno what your process is, but try to see if you can recreate that characteristic, goes away with flash, reccurs as the natural learning phase completes.

If that is the case, and you can find what params merc plays with for the learning phase. thought occured, there is load **** in the tranny module that also learn, if you drive auto, a factor.
then you can presume whats pushing the valve over the edge. another thought, since its electrically controlled, it is possible the ecu is telling it to open. that would be in the double hidden super secret table so, after the flash test, see if it does it when unplugged. ala' 2015.


solution?

what does your diff fluid look like at current levels?

what does a tuner do after finding the point where adding a degree of timing shows a bit of torque loss?
 

·
Premium Member
Joined
·
351 Posts
whats your WGDC when it happens?

IF
the wgdc is pinned, and excessive boost is still being seen, engineers have options

spark retard
spark cut
fuel cut



and, perhaps opening that other hole in the manifold your electric valve
 

·
Registered
Joined
·
264 Posts
Slightly related, I was looking under the hood yesterday, trying to learn this engine.
The wastegate actuator is the first disappointment I found in the design of this engine.
It is mounted all the way on the other side of the engine, there are basically 3 ft of hoses that lead to it (I am exaggerating).
And the second thing is that it's a 2-port actuator, the interrupt style.
As an example, in the Subaru World, the actuator was 12" away from the wastegate capsule and eeeeveryone tried to move it closer. Then in 2012, the factory attached the actuator to the intake manifold, only 3" away from the capsule.
Having 24" of hose between the two screams "modify me!"
I mean, back in the day when I cared about warranty in the Subaru, I bought fuel steel tube and replaced the rubber tube to my wastegate with that and small rubber couplings. .... it didn't make that big of a difference.

But another thing was replacing the 2-port actuator with a 3-port. The routing of the hoses changes.

Now that I'm thinking about it, I believe this car has a vacuum pump and that's why the routing is so long. But while the vacuum pump may be necessary ... maybe for finely tuned vacuum for the transmission?, no such thing is needed for the wastegate.
 
1 - 7 of 7 Posts
Top