FIREfreezerC250

Are you being serious? You just say "high pressure fuel pump" with no context, lol.

If you're being serious, can you please explain why you think it's that?

Odd Piggy

Way back I mentioned injectors in relation to the P0172 DTC. The HPFP is part of that system. So maybe. But I thought that usually has a DTC (P0087?) and turns on the CEL. There is also a fuel rail pressure sensor in that mix, but that definitely turns on the CEL and is obvious on real time data if it’s bad.

spb147

Out of curiosity, How are the gear changes holding up?

FIREfreezerC250

It's shifting nicely! Upshifts 1>2 and 2>3 are barely even noticeable now.

spb147

Going back to the HPFP, is there much known about how they fail (eg using bad or lower grade fuel - rust etc)? Was there ever a portion of the W204 M271 affected (eg X date to X date and/or based on manufactured site) or all can fail regardless of manufacture date, site and usage?
whats the overall cost of replacing the HPFP?

Edit: found the total cost to be around ~$1700 per other threads

meazz1

@FIREfreezerC250 Can you list or upload the work invoice or the work the dealer performed, you can blurred out any sensitive info before posting?
Did you have a talk with the dealer and told them the issue not resolved?
They should attempt to fix it again or refund, they can't just take your money and not address the problem you initially went there for, my 2 cents.

FIREfreezerC250

See, that's what I was thinking! They better do something for me! No, I haven't contacted them yet, but I am definitely going to today.

Yes, I will upload the entire maintenance history, just give me a second.

FIREfreezerC250

Here are pictures of all the documents I have. They are in no specific order.

https://imgur.com/a/6LCo8gm

FIREfreezerC250

Another update (sorry for the double posting).

I just got off the phone with iAutohaus. They are going to take another look at my car for no extra charge. They didn't even have a guess of what it could be this time. Hopefully we can figure this out once and for all, soon.

The car goes back in on March 31st. I could have sent it back in earlier, but I wanted a little more time with my car before it goes away for the 4th time lol.

FIREfreezerC250

Update:

So I'm sitting in my car at the drive-thru window of Rolberto's and I'm staring at my tachometer because I was thinking "well It seems like the problem has gone away". I haven't experienced the sputtering rpms at ildle/stop in the past 3 days. And then in what can only be considered an act of comedic timing, as I am staring at the tach the check engine lights illuminate right below.

Does it ever end?

I stopped at Advance Auto Parts and checked the DTC (I still don't have a scanner, I know). Car is throwing a P0171, System too lean bank 1.

Any ideas? I still have my appointment on Friday for further diagnosis.

meazz1

The shop must have missed to a attach vacuum line or sensor probably.

spb147

any updates?

FIREfreezerC250

I have been so busy since I last posted, and a few family emergencies.

I haven't experienced the sputtering at idle for about two weeks. When I turn the car on from a cold start it feels like it's going to start sputtering, misfires a couple of times, really shaky and all over the place, but after a minute or two it balances out. Once it drops down to 800 rpm it settles down. It's still showing P0171. Maybe the computer had to re-orientate around the vacuum pressure numbers with the new valve cover. That's my best guess.

There is one more issue that it's having though. The throttle response is wacky. Sometimes it doesn't respond nearly as much as it should, and other times revs up with the slightest tap. The throttle body is a simple device and I don't see how it could goo bad, but it might have. What do you think it could be?

Once I fix this throttle response issue I'm going to take a break on repairs for a while.

FIREfreezerC250

I just wanted to reply one more time and say this.

The 2011-2014 Mercedes C250/C300 will shake from a cold start for about 5 minutes. It will seem like there is something wrong with the engine. You will spend thousands trying to figure it out, and after reading every single thing you can about this car, and even contacting Mercedes, you will realize that it is just part of the car. That's just the way it is. IDK how a car manufacturer is allowed to sell a car like that.

spb147

Did you fix the other issues like the throttle response and sputterinh?

FIREfreezerC250

I haven't replaced the throttle body yet, so it jumps around a tiny bit here and there, but not nearly as bad as before. All I have to do is replace the throttle body and that will go away, but it's barely ever happens anyway.

The sputtering stopped once I had the valve cover replaced. And yesterday the check engine light randomly turned off. So yeah, at this point in time everything (besides replacing the old throttle body) is working good now.

FIREfreezerC250

I was going through the car wash today and as soon as I got out my speakers stopped working. The head unit/nav unit is still on and it's showing the radio station but nothing is coming out of the speakers. I'm assuming a fuse was blown somehow, does anybody know how I could fix this? If it is a fuse, where do I find it?

Thanks in advance.

JettaRed

iTrader: (1)

Thinking way out of the box, are there any indications that the car was ever flood damaged? Flood damage doesn't always mean it was driven through a lake, but that there can be water leaks to the interior where the water will collect under the carpet in the floor pan. There may be wiring that got soaked as a result. If this happens, you will experience all sorts of "phantom problems" as a result. This is because water will wick it's way to what every connected electronics a wire is attached to and eventually corrode connections, etc.

I had a 2008 Infiniti GX35 with a door seal leak that allowed water to puddle in the floor pan under the carpet. After a while, strange things started happening with the engine -- rough idle, hard starts, CELs, and even the engine NOT turning off. I filed a claim with my insurance company and they totalled the car. Now, my insurance is USAA and while they are not the cheapest, they don't bull**** you. They told me that it will be cheaper for them to total the car than to pay the endless repairs they know will be likely.

FIREfreezerC250

Hmmm. Well the car is from Texas, but like you said that doesn't mean much because water damage can happen without it having been flooded.

I actually hadn't seen your response until just now. The reason I signed in is to ask for actually ask for your guys' opinion on this new problem I'm having. And now having read your response it may be related.

The problem is that every time I go through the carwash my speakers start making crazy noises, and it actually gets so bad that it gets that smell that happens when you push speakers to hard. A melting-ish kinda smell. I'm pretty sure you guys know what I'm talking about. So yeah, something definitely seems to be shorting out? Does anybody know how I can fix this? It's the back speakers that mainly make the popping sounds so I'm assuming water is leaking in somewhere on the back of the car. I also noticed that during the car wash water is leaking in from both sides, at the column that separates the front and back doors. Everytime this happens my speakers stop working completely for like 6 hours (I'm assuming until it dries off). Like, I need to get a carwash but I'm refraining from doing so because I don't want to damage the speakers/wiring anymore than it has already been damaged? Any advice people?

As for the main issue, the rough idling, I've been careful observing every time I start the car. It shakes for a minute or two until it reaches 75 degrees (the engine). Like clockwork, as soon as it hits 75 degrees you can feel the car like engage into some other mode and the shaking stops completely and the car acts normal.

Anyway. Hoping somebody can shed light on either of these problems... I've been saving up money and I'm about ready to take it back in to my mechanic again, to hopefully have the issue fixed this time. (already have replaced engine valve cover and transmission valve body trying to fix this damn issue).

I love this car, and I'm going to continue to take it into the shop until the problem is solved (it's personal now haha). It runs well besides the shaking for the first 1-2 minutes. (also I've noticed the engine is much more happy in Sport mode, is there any way to default it so that the car is automatically in sport mode when I turn it on?)

Thanks in advance everyone!

Odd Piggy

Speakers/water leak:
The location you described is called the B pillar. Leaks there are likely to be either from bad door gaskets or poor door alignment. Inspect the entire front and rear door gaskets carefully. A body shop should be able to help with door alignment checks.

Rough idle:
What you have observed sounds like exactly what’s happening. This may have been said before. As the car warms up, it switches the emission system from open loop to closed loop. It sounds like the problem is with the fixed mixture settings in open loop before the closed loop feedback from sensors allows the ECU to adjust for the best performance. I suppose the injectors could be out of spec, but not so far as to prevent the ECU from making the corrections. Monitoring the O2 sensors in real time with a scanner may shed some light on the issue.

Sport mode:
It will take a coder to set the Sport mode as default. It can also be set to start in the last used mode. It’s pretty simple for someone with the knowledge and the right tools. One of the local MB shops here has a coder, so you might find one locally. There is also a Benz Ninja that advertises here on MBWorld that could probably do it remotely.

FIREfreezerC250

Thanks for the feedback. I'll be taking it back in soon for them to hopefully finally fix this rough idle issue. "fixed mixture settings in open loop mode" sounds like exactly what the issue is. It just baffles me that if that is the case, why are mechanics and even the Benz dealership unable to understand that that's the issue. It makes no sense to me. Anyway, I'll keep you all updated once I get it back from the mechanic. Hopefully, this rough idle issue will be done once and for all.

Oh one more question. I am due for an oil change, but only in time, I haven't reached the allotted miles yet. If I haven't even came close to the mileage, should I put the oil change off? Or is the time aspect more important?

Odd Piggy

Don’t put off an oil change due at the 1 year interval. A car that’s not driven much never gets hot enough to drive off volatile diluents like unburned fuel and moisture. Those destroy the oil lubrication properties more effectively than hard driving.

FIREfreezerC250

Hey everybody. I'm back again asking for some advice about my car.

So the passenger side window broke and wouldn't roll up. I had it fixed for $420 (the regulator is riveted in instead of bolted in, and also they are proprietary rivets... ugh), but they got my car super dirty while they were fixing it, so I go to take it through a carwash.

Well, I go through one of those automatic car wash machines, and halfway through my speakers stop working... Something got wet and started shorting and making a bunch of hissing, cracking, and popping noises, and now there is no output from the speakers whatsoever...

This exact situation happened before, but the speakers started working again after about 30 hours. This time, they did not ever come back.

Does anybody have any ideas on how to get my speakers working again? The navigation unit is on and it shows that it's on a certain radio station, but nothing is coming out of any of the speakers.

Thanks for your time guys, I appreciate the help.

BenzNinja

iTrader: (4)

open up the doors where the suspect speakers are
dry out
fix leak
check amp fuse
if no amp and amp is in the head unit you likely smoked the amp part in it

JettaRed

iTrader: (1)

"Proprietary rivets"? What BS that is! How is a rivet proprietary? And even if it is, use a nut and bolt and Loctite (red) the nut in place.

By the way, every window regulator I have ever worked on has been riveted in place. You drill out the original and replace it with another rivet or a small bolt and nut.