Replacing AIR pump
Thread Starter
Super Member
Joined: Dec 2002
Posts: 560
Likes: 1
From: FL
2000 S500 Brilliant Silver, 1990 BMW 735iL, 1971 Pontiac Trans Am 455 HO, 1976 Pontiac Formula 400
Replacing AIR pump
I have the dreaded CEL with code P0140 and a local non-dealer MB shop said it is the AIR pump. The cost is high at $800 for the part.
I found a place autohauzaz that has it, a Bosch part for only $137. Is this what MB uses in the car and is it an easy DIY project?
Thanks
I found a place autohauzaz that has it, a Bosch part for only $137. Is this what MB uses in the car and is it an easy DIY project?
Thanks
Junior Member
Joined: Dec 2008
Posts: 32
Likes: 0
From: North Georgia, USA
S430,300D X2,190E X2,280
Crankin,
Code P0410 may well mean a faulty secondary air pump....but it might not. The relay MB put in there is a POS. It could be sporadically sticking...not providing contact at all, or in the case of a dead air pump, completely stuck closed which would burn that puppy up in short order. It is also possible that the cast tubes in the heads are clogged which makes for a really bad day. The rubber air tube could be cracked or the vacuum line to the diaphragm could be faulty. For a pump test, unplug the harness and power the blower motor with 12 volts directly. If it's very noisy or does nothing you may have found at least part of your problem.
I have had this problem and, at first, I let the dealer walk me through the diagnostic process. Learned a lot....like, the O2 sensor is responsible for reading the results of the secondary air systems operation. If one or both of your O2 sensors is screwy; it can trigger a P1401 code but have absolutely nothing to do with the air pump, air lines, relay, etc. Not likely without an O2 sensor/AF mixture code as well but the SA said he's seen it.
Luckily for me, it was the relay. Unluckily, it burned out the air pump. Always replace a suspect relay! I refused to pay the $789 asked for the pump so I started looking around. The vendor you mentioned does sell the pump at a stupid cheap price compared to a dealer. I bought one, along with a Hella relay, and have had great success. It is an OEM Bosch pump and even has the MB part # on the pump body so I assume it is the same as I could have paid big change for. Could be wrong about that but given the performance of the pump; I don't really care. It is exact down to the most minute detail, though.
Installing it is about as easy as any repair you will ever see on a W220. Pop off the front engine cover and it will be staring you straight in the face. The method of removal is obvious once you get a good look at it. This is a good time to check the soft air lines and the vacuum lines. If they look even a bit old, cracked, worn; replace them. They are cheap and yet another possible causal factor for P0410. Also test the vacuum diaphragm with a MightVac as they can get cruddy and stick either open or closed. So long as the diaphragm itself is intact; these jewels can be cleaned restoring proper operation.
Sorry about being long winded. The $1,000 I saved on this issue has me a bit jazzed. If you have specific question about R&R; I'll try to help if I can. Don't have time to post regularly most of the time, though.
Sam
Code P0410 may well mean a faulty secondary air pump....but it might not. The relay MB put in there is a POS. It could be sporadically sticking...not providing contact at all, or in the case of a dead air pump, completely stuck closed which would burn that puppy up in short order. It is also possible that the cast tubes in the heads are clogged which makes for a really bad day. The rubber air tube could be cracked or the vacuum line to the diaphragm could be faulty. For a pump test, unplug the harness and power the blower motor with 12 volts directly. If it's very noisy or does nothing you may have found at least part of your problem.
I have had this problem and, at first, I let the dealer walk me through the diagnostic process. Learned a lot....like, the O2 sensor is responsible for reading the results of the secondary air systems operation. If one or both of your O2 sensors is screwy; it can trigger a P1401 code but have absolutely nothing to do with the air pump, air lines, relay, etc. Not likely without an O2 sensor/AF mixture code as well but the SA said he's seen it.
Luckily for me, it was the relay. Unluckily, it burned out the air pump. Always replace a suspect relay! I refused to pay the $789 asked for the pump so I started looking around. The vendor you mentioned does sell the pump at a stupid cheap price compared to a dealer. I bought one, along with a Hella relay, and have had great success. It is an OEM Bosch pump and even has the MB part # on the pump body so I assume it is the same as I could have paid big change for. Could be wrong about that but given the performance of the pump; I don't really care. It is exact down to the most minute detail, though.
Installing it is about as easy as any repair you will ever see on a W220. Pop off the front engine cover and it will be staring you straight in the face. The method of removal is obvious once you get a good look at it. This is a good time to check the soft air lines and the vacuum lines. If they look even a bit old, cracked, worn; replace them. They are cheap and yet another possible causal factor for P0410. Also test the vacuum diaphragm with a MightVac as they can get cruddy and stick either open or closed. So long as the diaphragm itself is intact; these jewels can be cleaned restoring proper operation.
Sorry about being long winded. The $1,000 I saved on this issue has me a bit jazzed. If you have specific question about R&R; I'll try to help if I can. Don't have time to post regularly most of the time, though.
Sam
Junior Member
Joined: Jul 2010
Posts: 15
Likes: 0
'03 S600 AMG
Wow, am I glad I found this post. Thanks for the wind..
Crankin,
Code P0410 may well mean a faulty secondary air pump....but it might not. The relay MB put in there is a POS. It could be sporadically sticking...not providing contact at all, or in the case of a dead air pump, completely stuck closed which would burn that puppy up in short order. It is also possible that the cast tubes in the heads are clogged which makes for a really bad day. The rubber air tube could be cracked or the vacuum line to the diaphragm could be faulty. For a pump test, unplug the harness and power the blower motor with 12 volts directly. If it's very noisy or does nothing you may have found at least part of your problem.
I have had this problem and, at first, I let the dealer walk me through the diagnostic process. Learned a lot....like, the O2 sensor is responsible for reading the results of the secondary air systems operation. If one or both of your O2 sensors is screwy; it can trigger a P1401 code but have absolutely nothing to do with the air pump, air lines, relay, etc. Not likely without an O2 sensor/AF mixture code as well but the SA said he's seen it.
Luckily for me, it was the relay. Unluckily, it burned out the air pump. Always replace a suspect relay! I refused to pay the $789 asked for the pump so I started looking around. The vendor you mentioned does sell the pump at a stupid cheap price compared to a dealer. I bought one, along with a Hella relay, and have had great success. It is an OEM Bosch pump and even has the MB part # on the pump body so I assume it is the same as I could have paid big change for. Could be wrong about that but given the performance of the pump; I don't really care. It is exact down to the most minute detail, though.
Installing it is about as easy as any repair you will ever see on a W220. Pop off the front engine cover and it will be staring you straight in the face. The method of removal is obvious once you get a good look at it. This is a good time to check the soft air lines and the vacuum lines. If they look even a bit old, cracked, worn; replace them. They are cheap and yet another possible causal factor for P0410. Also test the vacuum diaphragm with a MightVac as they can get cruddy and stick either open or closed. So long as the diaphragm itself is intact; these jewels can be cleaned restoring proper operation.
Sorry about being long winded. The $1,000 I saved on this issue has me a bit jazzed. If you have specific question about R&R; I'll try to help if I can. Don't have time to post regularly most of the time, though.
Sam
Code P0410 may well mean a faulty secondary air pump....but it might not. The relay MB put in there is a POS. It could be sporadically sticking...not providing contact at all, or in the case of a dead air pump, completely stuck closed which would burn that puppy up in short order. It is also possible that the cast tubes in the heads are clogged which makes for a really bad day. The rubber air tube could be cracked or the vacuum line to the diaphragm could be faulty. For a pump test, unplug the harness and power the blower motor with 12 volts directly. If it's very noisy or does nothing you may have found at least part of your problem.
I have had this problem and, at first, I let the dealer walk me through the diagnostic process. Learned a lot....like, the O2 sensor is responsible for reading the results of the secondary air systems operation. If one or both of your O2 sensors is screwy; it can trigger a P1401 code but have absolutely nothing to do with the air pump, air lines, relay, etc. Not likely without an O2 sensor/AF mixture code as well but the SA said he's seen it.
Luckily for me, it was the relay. Unluckily, it burned out the air pump. Always replace a suspect relay! I refused to pay the $789 asked for the pump so I started looking around. The vendor you mentioned does sell the pump at a stupid cheap price compared to a dealer. I bought one, along with a Hella relay, and have had great success. It is an OEM Bosch pump and even has the MB part # on the pump body so I assume it is the same as I could have paid big change for. Could be wrong about that but given the performance of the pump; I don't really care. It is exact down to the most minute detail, though.
Installing it is about as easy as any repair you will ever see on a W220. Pop off the front engine cover and it will be staring you straight in the face. The method of removal is obvious once you get a good look at it. This is a good time to check the soft air lines and the vacuum lines. If they look even a bit old, cracked, worn; replace them. They are cheap and yet another possible causal factor for P0410. Also test the vacuum diaphragm with a MightVac as they can get cruddy and stick either open or closed. So long as the diaphragm itself is intact; these jewels can be cleaned restoring proper operation.
Sorry about being long winded. The $1,000 I saved on this issue has me a bit jazzed. If you have specific question about R&R; I'll try to help if I can. Don't have time to post regularly most of the time, though.
Sam
thanks.
Member
Joined: Jun 2010
Posts: 84
Likes: 5
2002 s500
Question: Is this the same configuration function as the W140? By that, does it turn on for 60 seconds when the car is first started and then never start again until the car is restarted (I believe the W140 did it to add extra O2 for the Cats during the rich start cycle of the car.)
