W211 - E220 CDI Prefacelift"
Thread Starter
Newbie
Joined: Feb 2022
Posts: 2
Likes: 0
Mercedes E220 CDI, W211 + E350 CDI W212
W211 - E220 CDI Prefacelift"
Hi guys,
So this issue is driving me crazy, so I hope someone could toss me in the right direction. I had this problem with broken thermostat, so I bought a new one (OEM) and made my local indie change this one. The other was one completely broken (never over 40c). They changed it, and when I received the car it felt a little heavy on the pedal, but car was going OK, but not really fine, at least felt a bit stiff in the pedal and acceleration. But engine temp was normal. Usually it stays in between 90-100 celcius now.
Not long after the car started like surging like crazy when cold, like really crazy (the rpm needle was bouncing like a maniac) until it reached like good temperature and this more or less stopped. After a little while suddenly this p0034 turbocharger/supercharger bypass valve control circuit low started showing up. Went back to the indie and they saw some oil drips around the turbo hose so they replaced the gasgets on them (without taking them out to check for eventuall cracks or something). When he did that suddenly EGR fault code appeared (while at indie). It was the p0403 exhaust gas recirculation control circuit.
The p0034 went away, but soon after (few days) it was back again. The card goes into limp mode, and really has uneven and bad power. He said the EGR was cutting of the turbo when in limp mode, so probably a egr change would fix things. Bought new (used, but in well condition) one, fitted it, took out battery, all codes gone. Worked for few kms, now back with engine light (yellow), p0034, p0404 and p0403 codes (2 egr codes and one turbo low circuit).
So I have lost faith in the indie, as this also happened after they swapped the thermostat. Could they have messed up something in the process or just unlucky chain of events?
I have told them to check the turbo hose for cracks, but keeps telling me that that is unlickely as the car would smoke heavily.
Any help in any direction is highly appreciated. Thank you.
So this issue is driving me crazy, so I hope someone could toss me in the right direction. I had this problem with broken thermostat, so I bought a new one (OEM) and made my local indie change this one. The other was one completely broken (never over 40c). They changed it, and when I received the car it felt a little heavy on the pedal, but car was going OK, but not really fine, at least felt a bit stiff in the pedal and acceleration. But engine temp was normal. Usually it stays in between 90-100 celcius now.
Not long after the car started like surging like crazy when cold, like really crazy (the rpm needle was bouncing like a maniac) until it reached like good temperature and this more or less stopped. After a little while suddenly this p0034 turbocharger/supercharger bypass valve control circuit low started showing up. Went back to the indie and they saw some oil drips around the turbo hose so they replaced the gasgets on them (without taking them out to check for eventuall cracks or something). When he did that suddenly EGR fault code appeared (while at indie). It was the p0403 exhaust gas recirculation control circuit.
The p0034 went away, but soon after (few days) it was back again. The card goes into limp mode, and really has uneven and bad power. He said the EGR was cutting of the turbo when in limp mode, so probably a egr change would fix things. Bought new (used, but in well condition) one, fitted it, took out battery, all codes gone. Worked for few kms, now back with engine light (yellow), p0034, p0404 and p0403 codes (2 egr codes and one turbo low circuit).
So I have lost faith in the indie, as this also happened after they swapped the thermostat. Could they have messed up something in the process or just unlucky chain of events?
I have told them to check the turbo hose for cracks, but keeps telling me that that is unlickely as the car would smoke heavily.
Any help in any direction is highly appreciated. Thank you.
Thread Starter
Newbie
Joined: Feb 2022
Posts: 2
Likes: 0
Mercedes E220 CDI, W211 + E350 CDI W212
Hi guys,
So this issue is driving me crazy, so I hope someone could toss me in the right direction. I had this problem with broken thermostat, so I bought a new one (OEM) and made my local indie change this one. The other was one completely broken (never over 40c). They changed it, and when I received the car it felt a little heavy on the pedal, but car was going OK, but not really fine, at least felt a bit stiff in the pedal and acceleration. But engine temp was normal. Usually it stays in between 90-100 celcius now.
Not long after the car started like surging like crazy when cold, like really crazy (the rpm needle was bouncing like a maniac) until it reached like good temperature and this more or less stopped. After a little while suddenly this p0034 turbocharger/supercharger bypass valve control circuit low started showing up. Went back to the indie and they saw some oil drips around the turbo hose so they replaced the gasgets on them (without taking them out to check for eventuall cracks or something). When he did that suddenly EGR fault code appeared (while at indie). It was the p0403 exhaust gas recirculation control circuit.
The p0034 went away, but soon after (few days) it was back again. The card goes into limp mode, and really has uneven and bad power. He said the EGR was cutting of the turbo when in limp mode, so probably a egr change would fix things. Bought new (used, but in well condition) one, fitted it, took out battery, all codes gone. Worked for few kms, now back with engine light (yellow), p0034, p0404 and p0403 codes (2 egr codes and one turbo low circuit).
So I have lost faith in the indie, as this also happened after they swapped the thermostat. Could they have messed up something in the process or just unlucky chain of events?
I have told them to check the turbo hose for cracks, but keeps telling me that that is unlickely as the car would smoke heavily.
Any help in any direction is highly appreciated. Thank you.
So this issue is driving me crazy, so I hope someone could toss me in the right direction. I had this problem with broken thermostat, so I bought a new one (OEM) and made my local indie change this one. The other was one completely broken (never over 40c). They changed it, and when I received the car it felt a little heavy on the pedal, but car was going OK, but not really fine, at least felt a bit stiff in the pedal and acceleration. But engine temp was normal. Usually it stays in between 90-100 celcius now.
Not long after the car started like surging like crazy when cold, like really crazy (the rpm needle was bouncing like a maniac) until it reached like good temperature and this more or less stopped. After a little while suddenly this p0034 turbocharger/supercharger bypass valve control circuit low started showing up. Went back to the indie and they saw some oil drips around the turbo hose so they replaced the gasgets on them (without taking them out to check for eventuall cracks or something). When he did that suddenly EGR fault code appeared (while at indie). It was the p0403 exhaust gas recirculation control circuit.
The p0034 went away, but soon after (few days) it was back again. The card goes into limp mode, and really has uneven and bad power. He said the EGR was cutting of the turbo when in limp mode, so probably a egr change would fix things. Bought new (used, but in well condition) one, fitted it, took out battery, all codes gone. Worked for few kms, now back with engine light (yellow), p0034, p0404 and p0403 codes (2 egr codes and one turbo low circuit).
So I have lost faith in the indie, as this also happened after they swapped the thermostat. Could they have messed up something in the process or just unlucky chain of events?
I have told them to check the turbo hose for cracks, but keeps telling me that that is unlickely as the car would smoke heavily.
Any help in any direction is highly appreciated. Thank you.
Newbie
Joined: Aug 2025
Posts: 1
Likes: 0
W211, W124, R129
