Hi everyone
appreciate your support & feedback on my coronial issue , i have a 2013 Mercedes E350 3.5L V6 (M 276.957) engine
- Recently i had my (driver side) fuel pump ) top area crack and leak so I've replaced it with HELLA new one
- Drove it for couple of days without any issue
- A week later had my Torque converter replaced (overhauled) car wasn't pulling very well now so much better and shifting improved as well
- Currently am facing something strange when i cold start the car (after being set in garage for like 8hours+) it starts well but rough and vibe during idle & acceleration and deceleration (feels like a V8 hemi thing)
- When i drive it a bit on the high way it gets smoother by time which is also strange for me
- So i plugged my OBD reader and found Pending Code p2540 low pressure fuel system sensor circuit range/performance

 

I’m getting the same code. I believe this code has been here since I got the car at 109,000 miles that has 120,000 miles now. When I plugged in my BlueDriver, it says fuel pressure sensor circuit implausible. i’ve always noticed a humming towards the front of the car as well as when I press the gas it hesitates and then goes off like a turbo engine when it’s naturally aspirated V6. I don’t have any issues starting the car and I’m getting an average MPG of 18.5 in New York City could’ve just be the fuel pressure sensor or is it something bigger. It’s also failing the inspection check on the scanner. Any advice or suggestions would be appreciated!

 

Hi Doejax

have you replaced your fuel pump or filter recently ?
are you facing any of those symptoms ? (rough and vibe during idle & acceleration and deceleration )

 

I don’t know if the previous owner has but I haven’t replaced neither. I did get a check engine light and my RPMs were fluctuating but I did a spark plug and ignition coil change and that resolve that issue and it runs much better. I have harsh shifts around third gear and I would say on startup a rattles a little then smoothens out and I definitely feel vibrations around 55 to 75 mph but that could just be tire balance even though I aligned and balanced my tires, but I have a strong feeling the tire shop didn’t do a good job at balancing

 

This report has the low pressure sensor pointed all over it... yet don't rush to conclusion.
This could be a no-part-fix !?



low pressure fuel sensor

Go ahead and read the fuel sensor output to see what it reads then
how reported pressure goes after you stop the engine and turn ignition back on to read pressure without pump running.

If SENSOR IS PROVEN OK then consider this...
---> The DC to 3-phase pump generates a huge amount of poorly filtered electrical noise.
-- capacitors are undersized
-- noisy pump wiring is extra long
-- GND is extra long to front
-- PWR is extra long to rear
-- The small signals wires are bundled with noisy pump.... eventually split them out of the harness bundle: glitchy power wires should not be bundled with small signal wires.

---> MB carefully stacked everything wrong borderline to create a sweet pickle.

This chaos really contrast with the advanced 3-phase technology.

 

hi there

lets say we have the P2540 code , what we will face as a symptoms ?
in my case all this started after replacing my fuel pump (i used HELLA) and repaired my torque convertor
car rough when starting and vibrates when i accelerate above 3k rpm ,

 

You know these fuel injection cars are computer driven. You need to use an MB scanner to read what data the ECU is working with.
How are your fuel pressures ??

 

cool , am actually planning to buy the original pump & filter first before going to any shop for diagnosing
meaning putting everything back to original form

 

i will check it out this weekend, if you could share any pictures so I know exactly what to look for that would be awesome! If not, that’s alright! Still appreciate the knowledge and suggestions

 

yes, I can, I have posted rework mentioned above....
Here it is! From posts #75 to #79 or so...

That thread was originally started to troubleshoot/rework the voltage yo-yo that drains batteries below 12.0V while driving.

The CAN-B wiring harness snakes between both SAM's right by the noisy pump module - that's why I got into fixing it knowing it had reliable pins.

The low pressure tank fuel pump controller runs on ECU VIP CAN-C that directly impacts delayed tranny shifts. CAN-C has to be in the very best shape.

Try to focuss on one module at a time to prevent being overwhelmed by unknown issues all over.

 

You can guess its not the pump as replacing it made no difference. It was a very fair bet.

It could be the filtration if high mileage and low pressure...measure it under load acceleration. It must be stable else engine get leaned when it need richer mixture.

 

I think @S-Prihadi might have some input on this.

 

You guys are godsend!

 

You wanna do... :
some general bug surgery
or
focussed troubleshooting??

 

​​​​​​​You might be correct as i changed only the pump (driver side) , i guess i have to change the other side as well which includes the filter and see
however my code is not fixed it appears and disappears and i never got check engine light i only see it on my scanner
will keep you posted guys

 

[QUOTE=CaliBenzDriver;9038323]You wanna do... :
some general bug surgery
or
focussed troubleshooting??
[/QU
honestly, I have no idea what I’m doing but once I take everything apart, then I usually tend to get a better idea. Any of you guys live in nyc? Wanna have a play date with my car and I?

 

[QUOTE=doejax;9038534]I am in Norcal... 4000Mi away

Try to troubleshoot issues with a scanner then go in for hands-on testing then last surgical repair.

The concept is to try not to disturb anything more what's needed,
else you fix 1 problem and create couple unforseen new ones.

Every good system comes with its own set of interesting opportunities usually impacting performance.

I can claim I successfully mastered the missing performance of ...:

• MS Windows kernel efficiency
• Samsung laggy hot Android tuning
• Bosch solderless CAN architecture

My core interest is the study of system's efficiency. Mercedes-Bosch is a prime example of how performance is impacted when not measured nor managed.

When so many things detune the powertrain it's worth fixing.

 

Dears , a trick i did and kinda solved the problem , use high octane fuel 95 + full tank and add fuel injector cleaner such as ( wynn`s fuel system cleaner)
perform it like 2 times in the same week , and erase the code if you have it it should `t come back again

best of luck every one

 

That is good news.