Long Cranking Problem, Hard to start..
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05 c230k 6spd
Ah screw it, its hard to get those damn black lock rings without hitting it with a hammer and screw driver, I dont feel like taking it out unless I necessarily have to replace the fuel pump. Can anyone else chime on on the fuel pressure test I did and what that noise in the video is?
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05 c230k 6spd
Not quite the same thing but yes he did replace his fuel pump. His failed to start the car at all so he had no choice. My car still starts and its been like 2 months with this problem. It just has a hard start, so it may not be the fuel pump. but I am sure its something fuel related. The tool cost 140 from the dealer, its stupid because that thing cost like 5-10 bucks to produce but w.e. I can do it with hammer and screwdriver
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05 c230k 6spd
OK so when I put the key in ignition to pressure system the psi on gauge go to about 20-30 and i can hear the fuel pump prime but then the psi on the gauge drop immediately. Then I start the car and the psi go up and down on the gauge till it starts and it stays at 32ish psi. Turn car off and psi goes back to 0 immediately. The way I understand it is that it shouldnt drop the pressure this fast at all? What problem would this point to?
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05 c230k 6spd
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
d1no - sorry for not being on the board - have friends out from Canada. You have insufficient fuel pressure. The injection system on a 230K is different to the V6 but you must have adequate pressure & the injectors must have full pressure at start up or the vehicle will not start.
Xhale's comments are correct. First suspects are the fuel pump, strainer, & filter with pressure regulator.
Your video is indistinct but that high pitched whine sounds like the fuel pump screaming it's lungs off & cavitating. Listen to it with the back seat out - you should be able to easily hear the pump. It will cavitate/have trouble reaching pressure, if it is worn or the strainer is blocked.
Good luck & let us know - your problem is fuel.
Xhale's comments are correct. First suspects are the fuel pump, strainer, & filter with pressure regulator.
Your video is indistinct but that high pitched whine sounds like the fuel pump screaming it's lungs off & cavitating. Listen to it with the back seat out - you should be able to easily hear the pump. It will cavitate/have trouble reaching pressure, if it is worn or the strainer is blocked.
Good luck & let us know - your problem is fuel.
Last edited by Glyn M Ruck; Feb 14, 2011 at 12:37 PM.
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
d1no - sorry for not being on the board - have friends out from Canada. You have insufficient fuel pressure. The injection system on a 230K is different to the V6 but you must have adequate pressure & the injectors must have full pressure at start up or the vehicle will not start.
Xhale's comments are correct. First suspects are the fuel pump, strainer, & filter with pressure regulator.
Your video is indistinct but that high pitched whine sounds like the fuel pump screeming it's lungs off & cavitating. Listen to it with the back seat out - you should be able to easily hear the pump. It will cavitate/have trouble reaching pressure, if it is worn or the strainer is blocked.
Good luck & let us know - your problem is fuel.
Xhale's comments are correct. First suspects are the fuel pump, strainer, & filter with pressure regulator.
Your video is indistinct but that high pitched whine sounds like the fuel pump screeming it's lungs off & cavitating. Listen to it with the back seat out - you should be able to easily hear the pump. It will cavitate/have trouble reaching pressure, if it is worn or the strainer is blocked.
Good luck & let us know - your problem is fuel.
I would suggest you replace the fuel filter again to eliminate the pressure regulator. If you still have inadequate pressure, your fuel pump is on the way out. If you want a brand new OEM fuel filter, I will send you a brand new one for cheap, as I can't use it on my car.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
Correct John - d1no's car will have the old US set up & location of items as you have listed. I would do filter first as it was the last thing disturbed. Check piping to filter for dirt or internal delamination.
Last edited by Glyn M Ruck; Feb 14, 2011 at 03:39 PM.
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05 c230k 6spd
Ok guys thanks for replies. As of yesterday I took the back seat out and all the insulation and cover and have been driving like that. Holy crap car is loud now. The pumps makes so much noise, fuel sloshing and just road noise. Its amazing how the insulation and back seat dampen everything.
Glyn on the noise I was asking about its not from the fuel pump area its more like a buzzing from the ecu/maf/air intake location. Could it be the supercharger when the car is turned off? I assume its normal maybe im just more sensitive to it now.
Also on a side note, temp has been in the high 50s and the problem is still there on startup so deff not temp related.
John I pmed u on the filter.
Glyn on the noise I was asking about its not from the fuel pump area its more like a buzzing from the ecu/maf/air intake location. Could it be the supercharger when the car is turned off? I assume its normal maybe im just more sensitive to it now.
Also on a side note, temp has been in the high 50s and the problem is still there on startup so deff not temp related.
John I pmed u on the filter.
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
Ok guys thanks for replies. As of yesterday I took the back seat out and all the insulation and cover and have been driving like that. Holy crap car is loud now. The pumps makes so much noise, fuel sloshing and just road noise. Its amazing how the insulation and back seat dampen everything.
Glyn on the noise I was asking about its not from the fuel pump area its more like a buzzing from the ecu/maf/air intake location. Could it be the supercharger when the car is turned off? I assume its normal maybe im just more sensitive to it now.
Also on a side note, temp has been in the high 50s and the problem is still there on startup so deff not temp related.
John I pmed u on the filter.
Glyn on the noise I was asking about its not from the fuel pump area its more like a buzzing from the ecu/maf/air intake location. Could it be the supercharger when the car is turned off? I assume its normal maybe im just more sensitive to it now.
Also on a side note, temp has been in the high 50s and the problem is still there on startup so deff not temp related.
John I pmed u on the filter.
The noise you are describing coming from the engine is probably the coolant recirculation pump. Mine was CLEARLY audible when I was troubleshooting the fuel pump. My wife kept saying she could hear the fuel pump, because she was mistaking the sound of the coolant recirculation pump running.
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05 c230k 6spd
The fuel pump is not that loudd when the car is idling but as soon as I take off the noise gets louder due to pumps working, road noise etc. But I guess I will try out the fuel filter and then move on to pump.. I should be able to get away with just replacing the main one behind driver side right? Sender level pump should be fine right?
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
The fuel pump is not that loudd when the car is idling but as soon as I take off the noise gets louder due to pumps working, road noise etc. But I guess I will try out the fuel filter and then move on to pump.. I should be able to get away with just replacing the main one behind driver side right? Sender level pump should be fine right?
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From: Boston, MA
'14 ML350, '13 C220 CDI, '07 C280, '98 ML320
Cars need one fuel pump and one fuel level sender unit. I wonder why MB put 2 fuel level sender units. Is the second fuel level sender unit supposed to be redundant? If one of the sender unit fails, the other will ensure we get the fuel level? If Mb wanted to cut cost of the car, they could have removed the second fuel level sender unit; I wonder why they didn't.
Last edited by pcy; Feb 14, 2011 at 08:37 PM.
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05 c230k 6spd
Cars need one fuel pump and one fuel level sender unit. I wonder why MB put 2 fuel level sender units. Is the second fuel level sender unit supposed to be redundant? If one of the sender unit fails, the other will ensure we get the fuel level? If Mb wanted to cut cost of the car, they could have removed the second fuel level sender unit; I wonder why they didn't.
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From: Llandudno, Cape Town, South Africa
late 2009 CLK 350 Coupe Elegance, '65 Jaguar S Type wires
2 senders to average the content of the two saddle tanks - it's overkill but it's a Benz. I think John has hit the nail on the head. I think you are hearing the coolant recirculation pump up front.
I'm pleased to hear that John's VDO pump is quiet - because the Bosch pumps make an angry little buzz that I am aware of - as is Chris Brown & others. My car's pump, like splinter's & John's, is on the other side of the car. Older US cars have it on your driver's side.
It certainly sounds (& measures) as though your fuel pump is having a hard time. Now we need to find out why - blocked filter/bad pressure regulator, strainer or piping. Or the pump itself. I have a horrible feeling it's the pump but let's go through the system in systematic fashion & fix it once and for all so you can get on with life.
I'm pleased to hear that John's VDO pump is quiet - because the Bosch pumps make an angry little buzz that I am aware of - as is Chris Brown & others. My car's pump, like splinter's & John's, is on the other side of the car. Older US cars have it on your driver's side.
It certainly sounds (& measures) as though your fuel pump is having a hard time. Now we need to find out why - blocked filter/bad pressure regulator, strainer or piping. Or the pump itself. I have a horrible feeling it's the pump but let's go through the system in systematic fashion & fix it once and for all so you can get on with life.
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05 c230k 6spd
2 senders to average the content of the two saddle tanks - it's overkill but it's a Benz. I think John has hit the nail on the head. I think you are hearing the coolant recirculation pump up front.
I'm pleased to hear that John's VDO pump is quiet - because the Bosch pumps make an angry little buzz that I am aware of - as is Chris Brown & others. My car's pump, like splinter's & John's, is on the other side of the car. Older US cars have it on your driver's side.
It certainly sounds (& measures) as though your fuel pump is having a hard time. Now we need to find out why - blocked filter/bad pressure regulator, strainer or piping. Or the pump itself. I have a horrible feeling it's the pump but let's go through the system in systematic fashion & fix it once and for all so you can get on with life.
I'm pleased to hear that John's VDO pump is quiet - because the Bosch pumps make an angry little buzz that I am aware of - as is Chris Brown & others. My car's pump, like splinter's & John's, is on the other side of the car. Older US cars have it on your driver's side.
It certainly sounds (& measures) as though your fuel pump is having a hard time. Now we need to find out why - blocked filter/bad pressure regulator, strainer or piping. Or the pump itself. I have a horrible feeling it's the pump but let's go through the system in systematic fashion & fix it once and for all so you can get on with life.
If the filter comes in by sat I will do that and report back with my fuel pressure and starting. I really hope my last fuel filter was somehow defective and this new one fixes it but it will probably turn out to be somethin more expensive
. But thanks for helping guys
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From: NE. TN
06 C350 sport 6MT
had a horrible time with engine sttering and dedcreaqse power aqnd occas stalling, added 3oz of stabil in 1/2 tank of gas and now runs like a freight train, prior to this i disconnected the battery, ran a bottle of techron thru tank, and cleaned maf, i could not beleive the results, but the proof is in the pudding good luck
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05 c230k 6spd
OK whew I finally changed out the fuel filter with the one John sent me and holy crappp it was my 4 month old Purolator fuel filter that was causing all these problems. Once I replaced the fuel filter the fuel pressure shot back up and its at 55psi with the car running and stays there after i shut the car off. When the fuel pump is priming the fuel pressure doesnt drop either. I cant beleive a fuel filter could cause all this.. WORD OF ADVICE. DONT BUY PUROLATOR BRAND FUEL FILTERR. ONLY BUY THE OEM MADE IN GERMANY STUFF.
On a seperate note I got a Check engine light could that be from changing fuel filter?
BTW thanks alot John for selling me the fuel filter for a discount
On a seperate note I got a Check engine light could that be from changing fuel filter?
BTW thanks alot John for selling me the fuel filter for a discount
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Joined: Dec 2006
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From: Camas, WA
2007 C230SS; 2014 ML350 BT
OK whew I finally changed out the fuel filter with the one John sent me and holy crappp it was my 4 month old Purolator fuel filter that was causing all these problems. Once I replaced the fuel filter the fuel pressure shot back up and its at 55psi with the car running and stays there after i shut the car off. When the fuel pump is priming the fuel pressure doesnt drop either. I cant beleive a fuel filter could cause all this.. WORD OF ADVICE. DONT BUY PUROLATOR BRAND FUEL FILTERR. ONLY BUY THE OEM MADE IN GERMANY STUFF.
On a seperate note I got a Check engine light could that be from changing fuel filter?
BTW thanks alot John for selling me the fuel filter for a discount
On a seperate note I got a Check engine light could that be from changing fuel filter?
BTW thanks alot John for selling me the fuel filter for a discount
Glad you don't need a new fuel pump.You have found what a lot of us have found, and non-OEM parts on these cars are not worth the hassle.
Should have not got a CEL from just changing the fuel filter. Grab an OBDII scanner, or stop by an autoparts store and have them scan it for you and post the code here, so we can figure it out.
