hi,
My car has low boost pressure issue at turbocharger 1. I tried everything to fix it:
Smoke leak test - no leaks
Inspect air intake hose, air intake to intercooler hose, turbo charger vacuum hoses (2 hoses)
I also checked turbo diverter valve. Actuated it, it is working fine. I removed and inspected it and there were no damage to rubber seal around it.it seemed all fine to me.
I vacuum tested turbo westegate actuator. in xentry, when engine is idling, it showed me 92% of boost and westegate moved when it is closed. however, when i closed it, it wents back around 0,5mm which is i think fine but i may be wrong The actuator is only work with vacuum, but when i blow to it through the hose, i realized it does not hold air. is it normal for w205?
I also realized that, the low boost occurs only on hot weathers, at 4000 rpm. It engages soft limb mode with no CEL. Wehn i drive car at cool weathers, no such issue (i experienced it only 1 time as i pushed car to limits to see if it occurs or not). Overall i experience issue in hot days. In addition car does not have any overheating issue, temperature gauge is always at same location.
What can cause this issue?
My car has low boost pressure issue at turbocharger 1. I tried everything to fix it:
Smoke leak test - no leaks
Inspect air intake hose, air intake to intercooler hose, turbo charger vacuum hoses (2 hoses)
I also checked turbo diverter valve. Actuated it, it is working fine. I removed and inspected it and there were no damage to rubber seal around it.it seemed all fine to me.
I vacuum tested turbo westegate actuator. in xentry, when engine is idling, it showed me 92% of boost and westegate moved when it is closed. however, when i closed it, it wents back around 0,5mm which is i think fine but i may be wrong The actuator is only work with vacuum, but when i blow to it through the hose, i realized it does not hold air. is it normal for w205?
I also realized that, the low boost occurs only on hot weathers, at 4000 rpm. It engages soft limb mode with no CEL. Wehn i drive car at cool weathers, no such issue (i experienced it only 1 time as i pushed car to limits to see if it occurs or not). Overall i experience issue in hot days. In addition car does not have any overheating issue, temperature gauge is always at same location.
What can cause this issue?
dagger22
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Quote:
My car has low boost pressure issue at turbocharger 1. I tried everything to fix it:
Smoke leak test - no leaks
Inspect air intake hose, air intake to intercooler hose, turbo charger vacuum hoses (2 hoses)
I also checked turbo diverter valve. Actuated it, it is working fine. I removed and inspected it and there were no damage to rubber seal around it.it seemed all fine to me.
I vacuum tested turbo westegate actuator. in xentry, when engine is idling, it showed me 92% of boost and westegate moved when it is closed. however, when i closed it, it wents back around 0,5mm which is i think fine but i may be wrong The actuator is only work with vacuum, but when i blow to it through the hose, i realized it does not hold air. is it normal for w205?
I also realized that, the low boost occurs only on hot weathers, at 4000 rpm. It engages soft limb mode with no CEL. Wehn i drive car at cool weathers, no such issue (i experienced it only 1 time as i pushed car to limits to see if it occurs or not). Overall i experience issue in hot days. In addition car does not have any overheating issue, temperature gauge is always at same location.
What can cause this issue?
Yes, our setup uses vacuum (instead of boost) to actuate the turbo flap. Have you tuned the car or upgraded any parts for performance before?Originally Posted by totu1111
hi,My car has low boost pressure issue at turbocharger 1. I tried everything to fix it:
Smoke leak test - no leaks
Inspect air intake hose, air intake to intercooler hose, turbo charger vacuum hoses (2 hoses)
I also checked turbo diverter valve. Actuated it, it is working fine. I removed and inspected it and there were no damage to rubber seal around it.it seemed all fine to me.
I vacuum tested turbo westegate actuator. in xentry, when engine is idling, it showed me 92% of boost and westegate moved when it is closed. however, when i closed it, it wents back around 0,5mm which is i think fine but i may be wrong The actuator is only work with vacuum, but when i blow to it through the hose, i realized it does not hold air. is it normal for w205?
I also realized that, the low boost occurs only on hot weathers, at 4000 rpm. It engages soft limb mode with no CEL. Wehn i drive car at cool weathers, no such issue (i experienced it only 1 time as i pushed car to limits to see if it occurs or not). Overall i experience issue in hot days. In addition car does not have any overheating issue, temperature gauge is always at same location.
What can cause this issue?
no, it is stock with 184 hp.
As far as i saw, it holds vacuum but again, when it is closed thru xentry, arm goes back aorund 0.5 to 1mm . Again, 1 mechanic says it is normal
As far as i saw, it holds vacuum but again, when it is closed thru xentry, arm goes back aorund 0.5 to 1mm . Again, 1 mechanic says it is normal
Quote:
Originally Posted by dagger22
Yes, our setup uses vacuum (instead of boost) to actuate the turbo flap. Have you tuned the car or upgraded any parts for performance before?
no, it is stock with 184 hp.
As far as i saw, it holds vacuum but again, when it is closed thru xentry, arm goes back aorund 0.5 to 1mm . Again, 1 mechanic says it is normal
dagger22
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As far as i saw, it holds vacuum but again, when it is closed thru xentry, arm goes back aorund 0.5 to 1mm . Again, 1 mechanic says it is normal
Did the workshop advised you on the code that you had as well?Originally Posted by totu1111
no, it is stock with 184 hp.As far as i saw, it holds vacuum but again, when it is closed thru xentry, arm goes back aorund 0.5 to 1mm . Again, 1 mechanic says it is normal
Especially since you mentioned that you encountered this only once (at cool weather), and other times in hot days.... best to monitor the air and coolant temps as well... the ecu cuts timing when the air temps and coolant temp hits a certain degree, but not sure if they would also try to cut boost.
Quote:
Especially since you mentioned that you encountered this only once (at cool weather), and other times in hot days.... best to monitor the air and coolant temps as well... the ecu cuts timing when the air temps and coolant temp hits a certain degree, but not sure if they would also try to cut boost.
Coolant temp is always at the same spot. i mean it does not move a bit forward or backward. Originally Posted by dagger22
Did the workshop advised you on the code that you had as well?Especially since you mentioned that you encountered this only once (at cool weather), and other times in hot days.... best to monitor the air and coolant temps as well... the ecu cuts timing when the air temps and coolant temp hits a certain degree, but not sure if they would also try to cut boost.
You wont believe me but mercedes one of my friend at dealer told me to not bring car over there because there was same car with same issue and they replace all of pipes because they could not find issue. and changing al pipes does not fix issue as well.
Is there any other cooler for turbo or anything like that? i mean weather in around 35 C when the issue happens.
Well i do have a diagnostics so i can i thing track temperature of both
