Hi guys,
Had this car for a long while now, but haven't driven it for over 9-10 months.
When I came back to it it threw up these two codes (using OBD2 bluetooth reader, and Torque App);
P0299 "Turbo Underboost Condition"
&
P2359 "boost pressure control maximum exceeded"
Previously it has a split in the top boost hose so i did a emergency fix with amalgamating tape, duck tape and hose clamps (was in central France for a holiday at the time). So I assume this finally gave up ghost, replaced that with a new hose (OEM). Unfortunately the problem didn't go away, kind of annoying because I thought my bodge job was, a bodge. Turned out it was just fine
.
It drives fine until around 50mph where boost creeps up, at around 0.9bar it goes into limp mode where it does not exceed over 3k rpm.
It does not have a hissing/wooshing sound under boost while on load however on lift off at higher rpm there is a slight hissing sound when stationary so I assume this is some redirect noise I am hearing rather than actual leaking?
I have noticed (new or perhaps it has always done this?), that on the second click of the ignition there is a relay/solenoid ticking over at the location of the electronic turbo actuator. The relay "click" quite constant in time, but it doesn't stop. Is that normal?
I can reset the codes with the Torque App, but it will go back onto this fault after putting some load on the car.
So scouring across the internet for answers I came across these checks;
# Check vacuum/ boost pipes to see if there are any tears or oil leaking (indicating of boost leak), try spraying soapy water to assist with leak checking.
I've taken each section apart and checked them, I saw very small spillage on a couple of the seal parts so I replaced those. Gave them a good wiggle aswell while having someone step of the loud pedal give no obvious signs of leaking.
FYI - really good website for searching part numbers (but its in Russian) ?????????? ???????????? ??????? ?? ???????? ??203 ????????? (c203). ??????? ????????? ? Mercedes Benz CL203 Sportcoupe (c203). ???????????? ????????. EPC, Tecdoc | Merc.com.ua
# Checked the intercooler, it looks to be fine and no oil residue, but not fired UV dye inside to check.
I've read that the electronic solenoid for the vanes could have given up the ghost and its not easy to get a replacement (ie you need to buy the turbo with it).
Or random things like EGR replacement, Oxygen, MAF sensor replacement, which majority of them doesn't seem to have much success over.
My "local" indie is Prestige Car Service but they are about 1:30hr away, which is fine if I can just drop the car off and it'll be fixed. But its likely to be, a few visits..
If there are any suggestions I could try out now to further diagnose- it would be great!
** Edit: No leaking from the manifold, no leaking on the hot side or cold side, nor EGR.. however there is some oil weeping/residue on the oil separator? but that doesn't seem to be on pressure. So I assume this not related.
Had this car for a long while now, but haven't driven it for over 9-10 months.
When I came back to it it threw up these two codes (using OBD2 bluetooth reader, and Torque App);
P0299 "Turbo Underboost Condition"
&
P2359 "boost pressure control maximum exceeded"
Previously it has a split in the top boost hose so i did a emergency fix with amalgamating tape, duck tape and hose clamps (was in central France for a holiday at the time). So I assume this finally gave up ghost, replaced that with a new hose (OEM). Unfortunately the problem didn't go away, kind of annoying because I thought my bodge job was, a bodge. Turned out it was just fine
.It drives fine until around 50mph where boost creeps up, at around 0.9bar it goes into limp mode where it does not exceed over 3k rpm.
It does not have a hissing/wooshing sound under boost while on load however on lift off at higher rpm there is a slight hissing sound when stationary so I assume this is some redirect noise I am hearing rather than actual leaking?
I have noticed (new or perhaps it has always done this?), that on the second click of the ignition there is a relay/solenoid ticking over at the location of the electronic turbo actuator. The relay "click" quite constant in time, but it doesn't stop. Is that normal?
I can reset the codes with the Torque App, but it will go back onto this fault after putting some load on the car.
So scouring across the internet for answers I came across these checks;
# Check vacuum/ boost pipes to see if there are any tears or oil leaking (indicating of boost leak), try spraying soapy water to assist with leak checking.
I've taken each section apart and checked them, I saw very small spillage on a couple of the seal parts so I replaced those. Gave them a good wiggle aswell while having someone step of the loud pedal give no obvious signs of leaking.
FYI - really good website for searching part numbers (but its in Russian) ?????????? ???????????? ??????? ?? ???????? ??203 ????????? (c203). ??????? ????????? ? Mercedes Benz CL203 Sportcoupe (c203). ???????????? ????????. EPC, Tecdoc | Merc.com.ua
# Checked the intercooler, it looks to be fine and no oil residue, but not fired UV dye inside to check.
I've read that the electronic solenoid for the vanes could have given up the ghost and its not easy to get a replacement (ie you need to buy the turbo with it).
Or random things like EGR replacement, Oxygen, MAF sensor replacement, which majority of them doesn't seem to have much success over.
My "local" indie is Prestige Car Service but they are about 1:30hr away, which is fine if I can just drop the car off and it'll be fixed. But its likely to be, a few visits..
If there are any suggestions I could try out now to further diagnose- it would be great!
** Edit: No leaking from the manifold, no leaking on the hot side or cold side, nor EGR.. however there is some oil weeping/residue on the oil separator? but that doesn't seem to be on pressure. So I assume this not related.
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