When you click on links to various merchants on this site and make a purchase, this can result in this site earning a commission. Affiliate programs and affiliations include, but are not limited to, the eBay Partner Network.
I wouldnt think CPS right off the bat. Although a complete failure could be the case, CPS issues typically happen when the engine is warm/hot with the engine cutting out in the middle of driving. You would wait for it to cool down, starts up again. Sometimes a CEL sometimes not.
Are you able to check fuel pressure?
Stupid question* is there fuel in the tank? (I had a friend with a faulty gauge, turns out tank was empty)
Last edited by vincheung; Jun 13, 2018 at 01:14 AM.
I wouldnt think CPS right off the bat. Although a complete failure could be the case, CPS issues typically happen when the engine is warm/hot with the engine cutting out in the middle of driving. You would wait for it to cool down, starts up again. Sometimes a CEL sometimes not.
Are you able to check fuel pressure?
Stupid question* is there fuel in the tank? (I had a friend with a faulty gauge, turns out tank was empty)
Doesn't start cold. didn't feel any cut out. Just went to start car in afternoon and no go. This would be the first time my car would need a tow. Car has been really reliable thus far.
It sounds like there is no gas. maybe the gas gauge is not working properly it says it has 1/4 tank. But oddly sounds like when it has no gas.
No I am not able to check fuel pressure. I checked all fuses and tried changing the fuel pump relay. Not sure which one back there is fuel pump. So I tried both.
Gonna try putting in more gas first. Before I tow it to the shop.
No I am not able to check fuel pressure. I checked all fuses and tried changing the fuel pump relay. Not sure which one back there is fuel pump. So I tried both.
Gonna try putting in more gas first. Before I tow it to the shop.
Remove the air cleaners and have someone crank the car(there is actually time to do it yourself) and give a small shot of brake cleaner or instant start into the throttle body. If she wants to fire it's a fuel issue, if not, possible CPS. I bought my Bosch CPS from the big ZON.
I would start with dumping in a few gallons of fuel before towing it. I still doubt it’s the CPS as the car is cold. Like I mentioned earlier, I had a friend with the same issue fuel showed 1/4 but he was in fact empty. I’ve had the same issue with my old S500. Pulled up to the gas pump, fiddled with wallet and the car cut out. I was swearing up and down about the CPS! 1/4 tank on the gauge and no fuel light, but tank was bone dry.
I would start with dumping in a few gallons of fuel before towing it. I still doubt it’s the CPS as the car is cold. Like I mentioned earlier, I had a friend with the same issue fuel showed 1/4 but he was in fact empty. I’ve had the same issue with my old S500. Pulled up to the gas pump, fiddled with wallet and the car cut out. I was swearing up and down about the CPS! 1/4 tank on the gauge and no fuel light, but tank was bone dry.
Very true, same thing happened to the wifes CLK. If adding gas to the tank doesn't work, I'd still check it from the TB.
I would start with dumping in a few gallons of fuel before towing it. I still doubt it’s the CPS as the car is cold. Like I mentioned earlier, I had a friend with the same issue fuel showed 1/4 but he was in fact empty. I’ve had the same issue with my old S500. Pulled up to the gas pump, fiddled with wallet and the car cut out. I was swearing up and down about the CPS! 1/4 tank on the gauge and no fuel light, but tank was bone dry.
LoL I was thinking the same. Because it sure sounds like it has no gas. I got fed up after checking every damn fuse in the car. I was really tempted to add gas. I should have tried spraying some brake cleaner in the throttle body first. I towed it. Well see what they say. I will report back with updates.
On a side note. I gotta bunch of new carbon fiber I want to put on so Im itching to get the car back. Thanks
Within a couple weeks of doing the warranty fuel tank replacement, my car up and quit. It was the fuel pump fuse. Replace fuse, 60k miles later and it hasn't done it since.
The SA said the fuel pump is bad. I just changed pumps and sending units with the new adapter plug recently. I have my doubts.
Have you ever heard the fuel pump just stop working after 3-4 months? Is the flters on the pump side or the sending unit side?
Yep it can happen, contaminated fuel plugs filter, pump then draws too much current frying the pump, 30amp fuse and or the relay. Lot's of searchable info under fuel pump, especially from sensei guru bbirdwell! If it is truly the pump (primary) the secondary is probably fine. Not sure if you turn your own wrenches but it's not that bad of DIY, can be messy if you got more than 1/4 tank of fuel. I would want to see the relay and 30amp fuse. https://mbworld.org/forums/w211-amg/...-pump-r-r.html
I don't turn wrenches anymore. My back wont allow me to work that much on my car lol. Other then small things.
OK so the shop forman says the system has 12 volts and there is no fuel pressure. So the pump is shot. I asked him how he thinks it happened on a new pump and filter? He is going to check the wiring to make sure its not burned or if indeed its the pump. But if it is the pump. Shouldn't there be some signs of overheating or something? This blows and will most certainly cut into the budget for the other things I had in mind.
He is going to get back to me tomorrow.
On a positive note. The car has been rock solid to me the last 10+ years of ownership and I mean cross country trips elevations changes and all. Its been a great daily and other then the items I had replaced under warranty. All I changed was the original air springs that lasted like 10+ years, alternator, All new bushings and control arms, and battery. That is literally it. All engine and trans scheduled service always performed at the dealer or indy shop. So I cant complain that the car has not treated me very well and has never left me stranded. Just blows that I just changed the pumps and filters. Rant over.
I don't turn wrenches anymore. My back wont allow me to work that much on my car lol. Other then small things. Shouldn't there be some signs of overheating or something?
In my case there war no charring at the pump plug, slight char on the relay socket. I think the fuse was doing it's job. It's possible to get a bad part out of the box. Is the repair still under warranty? I'm staying tuned for the out come
The SA said the fuel pump is bad. I just changed pumps and sending units with the new adapter plug recently. I have my doubts.
Have you ever heard the fuel pump just stop working after 3-4 months?
Is the flters on the pump side or the sending unit side?
This happened to me. The only time my car left me stranded and I had to have it towed. I took it in for the fuel pump/filter warranty repair and it turned out the dealer put used pumps in, and someone else from the dealership took home the "new" pumps for their own car. There is no primary or secondary pump. They both operate identically, and in tandem.
Even though the car has two fuel pumps, it requires the additional pressure from the second pump in order to transfer the fuel from the filter side (driver saddlebag) into the pump side (passenger saddlebag). You end up with fuel in the driver side of the tank, and bone dry on the pump side.
If your car has a 1/2 tank of fuel right now, that's your culprit.
Last edited by equitiesguy; Jun 20, 2018 at 03:40 AM.
[quote Even though the car has two fuel pumps, it requires the additional pressure from the second pump in order to transfer the fuel from the filter side (driver saddlebag) into the pump side (passenger saddlebag). You end up with fuel in the driver side of the tank, and bone dry on the pump side.If your car has a 1/2 tank of fuel right now, that's your culprit.
][/quote]
It's my understanding that only the primary pump energizes when the key is turned on and it pressurizers the fuel rail for start and fuel needs below 3k RPM. The second pump is energized when the fuel needs increase (above 3k RPM). The fuel return comes from the bottom of the sender (unless your running a modified looped fuel rail) back the the pump buckets. In my case the primary pump was shot but the secondary was fine. It may be possible, in my case, that if I switched the wiring clips on the pumps, I possibly could have limped home or get to a better place for a tow. If you skip ahead to 6:00 in the vid Tasos explains the return.
Negative. Both fuel pumps activate simultaneously and in tandem. In the 211/219 they are two stage fuel pumps for high fuel demand. I'm assuming we're strictly talking about the 55 series. 63 series engines I have little knowledge of, and would have to look it up specifically because they are controlled by a computer module rather than activation relays.
The return is simple for this system: the excess pressure is used to spin a small pump at the bottom of the filter, which siphons pumps the fuel back into the fuel baskets on the passenger side, all via the main fuel pumps. Certain cars have their own pump responsible for equalizing the tank. Mercedes uses the fuel pumps themselves.
Last edited by equitiesguy; Jun 20, 2018 at 12:04 PM.
Then why would only one of my pumps have fried? Bad out of the box?
I've noticed it's very easy to twist the lines in a way where it would effectively "kink" the line and create unexpected pressure. You have to be very careful when you run them from the filter side over the inside arch of the tank. Could also be bad out of the box.
I've noticed it's very easy to twist the lines in a way where it would effectively "kink" the line and create unexpected pressure. You have to be very careful when you run them from the filter side over the inside arch of the tank. Could also be bad out of the box.
It's been awhile since I was in there, but I believe everything was correct from dealership tank replacement. Very strange.... must have been a bad pump from manufacture.
FWIW, I monitor the amperage of each fuel pump every 10,000 miles. I'm watching one of the pumps continually drawing increased amperage compared to the other pump. Not a lot, but it's increased from 13.4 amps to 14.1 amps over 40,000 miles. The other pump has slightly decreased by about half an amp.
Last edited by bbirdwell; Jun 20, 2018 at 04:55 PM.
Well, they ran a test put 12 volts to the pumps and nothing. They said the pumps needs to be replaced that its defective, even being very slightly used. No charing, no burnt wires or lids, no burnt relay socket. good relay. Sucks for me I gotta buy just the pumps again and wait like 8 days to arrive. What a bummer.
Well, they ran a test put 12 volts to the pumps and nothing. They said the pumps needs to be replaced that its defective, even being very slightly used. No charing, no burnt wires or lids, no burnt relay socket. good relay. Sucks for me I gotta buy just the pumps again and wait like 8 days to arrive. What a bummer.
Hmmmm? If it were me, I'd change the sender unit also. 8 days for parts
Well, they ran a test put 12 volts to the pumps and nothing. They said the pumps needs to be replaced that its defective, even being very slightly used. No charing, no burnt wires or lids, no burnt relay socket. good relay. Sucks for me I gotta buy just the pumps again and wait like 8 days to arrive. What a bummer.
If it hasn't been that long, shouldn't it be under warranty?
