Fuel pump help needed
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
Fuel pump help needed
So, if you have been following this thread: https://mbworld.org/forums/c-class-w...ard-start.html you can see that my 07 C230 will not start. I replaced a known revised CPS, and still no start. Hooked up a fuel pressure gauge, and I have no pressure. Then, I checked the fuel pump fuse and relay, and they are good. Then, I tried to find the fuel pump under the seat to test it, and then I got a little confused. Here are the pics. This is the passenger side:
This is the drivers side:
So, after some digging around in WIS wiring diagrams, I found the wiring for the pump which is on the passenger side. But, then I am confused with this. Clearly the fuel line is attached on the driver's side, but the fuel pump on the passenger side has no fuel lines? How does that work? Where is the wiring for the 2nd level sending unit? Any help in sorting this out is appreciated. I don't want to tow it to the dealer to fix.
This is the drivers side:
So, after some digging around in WIS wiring diagrams, I found the wiring for the pump which is on the passenger side. But, then I am confused with this. Clearly the fuel line is attached on the driver's side, but the fuel pump on the passenger side has no fuel lines? How does that work? Where is the wiring for the 2nd level sending unit? Any help in sorting this out is appreciated. I don't want to tow it to the dealer to fix.
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05 c230k 6spd
http://www.installuniversity.com/mb/w203/w203/fp.html
Thats a DIY for fuel pump replacement on 02 c240.. Hopefully not much has changed and those pics help you a bit.
Thats a DIY for fuel pump replacement on 02 c240.. Hopefully not much has changed and those pics help you a bit.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
See my reply PM to yours.
The pump is on the LHS (drivers US) side on 99% of W203's. I have seen one car with it reversed.
The pump is on the LHS (drivers US) side on 99% of W203's. I have seen one car with it reversed.
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
http://www.installuniversity.com/mb/w203/w203/fp.html
Thats a DIY for fuel pump replacement on 02 c240.. Hopefully not much has changed and those pics help you a bit.
Thats a DIY for fuel pump replacement on 02 c240.. Hopefully not much has changed and those pics help you a bit.
I think those plastic covers need to come off to see all the pipe routing.
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05 c230k 6spd
Yep - That is how most cars are. But John has the final W203 with the fuel filter in the tank. From his pics above the pump is still seems to be on the drivers side of his car unless they moved it to make space for the filter. What I don't understand is why the wiring is so heavy to the passenger side which used to be a level sensor only.
I think those plastic covers need to come off to see all the pipe routing.
I think those plastic covers need to come off to see all the pipe routing.
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From: Orange County, CA
GMC - Miata - Trek - P-Car
If you haven’t already finished…
Almost certain the right hand side is the pump proper; mine was.
Some wires & hoses that connect with the RH pump run in the tank from the level sensor.
On the road as I post this. Will update further this evening if need be. Good luck amigo.
Almost certain the right hand side is the pump proper; mine was.
Some wires & hoses that connect with the RH pump run in the tank from the level sensor.
On the road as I post this. Will update further this evening if need be. Good luck amigo.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
John - I have trawled through the EPC & your car seems to be a crossover vehicle that looks more like a W204 than a W203 in this regard
The W204 has the fuel pump on the RH (passenger US) side of the car & one of the sensors & other gubbins on the LHS.
Your fuel system is not the same as earlier W203's
The W204 has the fuel pump on the RH (passenger US) side of the car & one of the sensors & other gubbins on the LHS.
Your fuel system is not the same as earlier W203's
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
If you haven’t already finished…
Almost certain the right hand side is the pump proper; mine was.
Some wires & hoses that connect with the RH pump run in the tank from the level sensor.
On the road as I post this. Will update further this evening if need be. Good luck amigo.
Almost certain the right hand side is the pump proper; mine was.
Some wires & hoses that connect with the RH pump run in the tank from the level sensor.
On the road as I post this. Will update further this evening if need be. Good luck amigo.
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Joined: Jun 2008
Posts: 19,942
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Your car should require the ring tool but the only way to know for certain is to check. Benz changed at some VIN number that I can't find.
Your car should have the external filter next to the tank with the built in pressure regulator. John's car has the filter inside the one tank module.
Your car s/b like this - Ignore the fact that this says M272 engine - John's car has M272 & the filter is in the tank:
https://mbworld.org/forums/attachmen...unction-1-.pdf
This - which side is the fuel pump nonsense of Benz got me into trouble with a member in my early days on the forum. I had presumed incorrectly that all cars were RHS. I also got involved with ChrisBrown's car which has a noisy pump & that was LHS IIRC.
Last edited by Glyn M Ruck; Jan 23, 2011 at 05:39 PM.
Thread Starter
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
Thanks for the replies. I am 99% certain the passenger side is the pump side. Those are heavy gauge wires as Glyn pointed out, and the color code matches what the WIS diagrams say is M3 (fuel pump). I realized when I was thinking about it that Splinter is right, and there has to be fuel lines and other wiring running to the other side.
Parts.com has the pump for $173. Going to call the stealer in the morning and see what they want for a pump.
Parts.com has the pump for $173. Going to call the stealer in the morning and see what they want for a pump.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Yes - the pump should be fine with that! As I said in PM the older Pierburg & Bosch pumps had 7 to 15 volt operating latitude.
Last edited by Glyn M Ruck; Jan 23, 2011 at 06:15 PM.
Thread Starter
Super Moderator
Joined: Dec 2006
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
Super Moderator
Joined: Jun 2008
Posts: 19,942
Likes: 191
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
No actually - VDO makes fuel pumps & maybe Merc has moved from Bosch & Pierburg to VDO.
I noticed the VDO in your top pic. They obviously make sensors & gauges as well. With bean counters around maybe VDO got the new contract. Imagine they would have to meet the same spec.
I'm old shool. If it has a Bosch injection system I wish they would keep it all Bosch. When I see all the trouble they have had with crap Delphi injectors on the diesel Blue Efficiency range I have to ask - why did they change???
I noticed the VDO in your top pic. They obviously make sensors & gauges as well. With bean counters around maybe VDO got the new contract. Imagine they would have to meet the same spec.
I'm old shool. If it has a Bosch injection system I wish they would keep it all Bosch. When I see all the trouble they have had with crap Delphi injectors on the diesel Blue Efficiency range I have to ask - why did they change???
Thread Starter
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Joined: Dec 2006
Posts: 2,403
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
Agreed.
The drivers side pic shows a Delphi part. Not sure if it is a pressure regulator, sending unit or what? I'll look at the schematic just for curiosity.
So, with all that said, I now am 100% sure the pump is toast. The real question is why it failed so soon? Think the fairly large quantities of E85 that passed through it had anything to do with it?
Glyn, I know you frequent the 204 forum, so any pump failures you can recall? I doubt there is many 204's up to the mileage of my 203, but interesting to see if the 204 start seeing early pump failures.
The drivers side pic shows a Delphi part. Not sure if it is a pressure regulator, sending unit or what? I'll look at the schematic just for curiosity.
So, with all that said, I now am 100% sure the pump is toast. The real question is why it failed so soon? Think the fairly large quantities of E85 that passed through it had anything to do with it?
Glyn, I know you frequent the 204 forum, so any pump failures you can recall? I doubt there is many 204's up to the mileage of my 203, but interesting to see if the 204 start seeing early pump failures.
No actually - VDO makes fuel pumps & maybe Merc has moved from Bosch & Pierburg to VDO.
I noticed the VDO in your top pic. They obviously make sensors & gauges as well. With bean counters around maybe VDO got the new contract. Imagine they would have to meet the same spec.
I'm old shool. If it has a Bosch injection system I wish they would keep it all Bosch. When I see all the trouble they have had with crap Delphi injectors on the diesel Blue Efficiency range I have to ask - why did they change???
I noticed the VDO in your top pic. They obviously make sensors & gauges as well. With bean counters around maybe VDO got the new contract. Imagine they would have to meet the same spec.
I'm old shool. If it has a Bosch injection system I wish they would keep it all Bosch. When I see all the trouble they have had with crap Delphi injectors on the diesel Blue Efficiency range I have to ask - why did they change???
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05 c230k 6spd
Your car should have the set up like installuniversity. There is one easy way to check which side the pump is mounted. Put your ear to the rear seat & listen for which side has the pump whine. If you can't hear it with the engine running the let the car stand overnight and you might hear it more easily as you switch on to crank. With the seat out you can clearly hear where the pump is. I should also point out that the 4 cylinder engines have a different injection system to the V6 although they share most tank etc parts.
Your car should require the ring tool but the only way to know for certain is to check. Benz changed at some VIN number that I can't find.
Your car should have the external filter next to the tank with the built in pressure regulator. John's car has the filter inside the one tank module.
Your car s/b like this - Ignore the fact that this says M272 engine - John's car has M272 & the filter is in the tank:
https://mbworld.org/forums/attachmen...unction-1-.pdf
This - which side is the fuel pump nonsense of Benz got me into trouble with a member in my early days on the forum. I had presumed incorrectly that all cars were RHS. I also got involved with ChrisBrown's car which has a noisy pump & that was LHS IIRC.
Your car should require the ring tool but the only way to know for certain is to check. Benz changed at some VIN number that I can't find.
Your car should have the external filter next to the tank with the built in pressure regulator. John's car has the filter inside the one tank module.
Your car s/b like this - Ignore the fact that this says M272 engine - John's car has M272 & the filter is in the tank:
https://mbworld.org/forums/attachmen...unction-1-.pdf
This - which side is the fuel pump nonsense of Benz got me into trouble with a member in my early days on the forum. I had presumed incorrectly that all cars were RHS. I also got involved with ChrisBrown's car which has a noisy pump & that was LHS IIRC.
Hey John how'd you get that price on the parts.com website. For me it shows 230$ when I look it up
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Thanks for the reply Glyn. So lets say I do require the ring thing, is there a way to take it out without it because the tool alone cost over 100 bucks. Yes my car has the fuel filter under the car next to the rear driver wheel. I might be having to replace my pump too if it fails soon.
Hey John how'd you get that price on the parts.com website. For me it shows 230$ when I look it up
Hey John how'd you get that price on the parts.com website. For me it shows 230$ when I look it up
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Joined: Jun 2008
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Alcohols can do awful things - I know - we had to tolerate Sasol heavy alcohols in our fuel for years & I have plenty of experience in Brazil with their hydrous & anhydrous alcohols.
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Joined: Jun 2008
Posts: 19,942
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Agreed.
The drivers side pic shows a Delphi part. Not sure if it is a pressure regulator, sending unit or what? I'll look at the schematic just for curiosity.
So, with all that said, I now am 100% sure the pump is toast. The real question is why it failed so soon? Think the fairly large quantities of E85 that passed through it had anything to do with it?
Glyn, I know you frequent the 204 forum, so any pump failures you can recall? I doubt there is many 204's up to the mileage of my 203, but interesting to see if the 204 start seeing early pump failures.
The drivers side pic shows a Delphi part. Not sure if it is a pressure regulator, sending unit or what? I'll look at the schematic just for curiosity.
So, with all that said, I now am 100% sure the pump is toast. The real question is why it failed so soon? Think the fairly large quantities of E85 that passed through it had anything to do with it?
Glyn, I know you frequent the 204 forum, so any pump failures you can recall? I doubt there is many 204's up to the mileage of my 203, but interesting to see if the 204 start seeing early pump failures.
Example - https://mbworld.org/forums/c-class-w...ight=fuel+pump
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Joined: Jun 2008
Posts: 19,942
Likes: 191
From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Benz over the years has cheapened many things to keep their cars cost competitive & it shows. I still remember the day Jürgen Schrempp informed the German board that their cars were "over engineered"
