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After market fuel pump quality

2K views 16 replies 6 participants last post by  Patch's 
#1 · (Edited)
Hi all,

Yesterday my car didn't start. It turned over but no start.
There was no fuel pressure. I checked the fuse, was OK, removed the relay, resistance was OK.
Then I changed the fuel filter, still no start.
The I applied direct voltage to the fuel pump, didn't hear any sounds.
Then I whacked the pump a few times with a small hammer, tried to start and the car started. Hmm...
So, I figured I will change the fuel pump next.
The OEM is about $200, there are many much cheaper ones between $50 and $100, all looking the same.
My question is does anyone have any experience with the after market ones or should I stick to the Bosch one? The car is MY 2000 E320 with 110k miles and I will keep it for two more years, the most.

Oh, I checked the codes, there was nothing related to.the engine.

Thanks.
 
#4 ·
Honestly that's what I was thinking, as one tow will easily cost me more than the price difference between an OEM and an after market pump.

However, the no-start condition shouldn't have been caused by a clogged filter and me whacking the pump shouldn't have made the pump work and the car start either.
So then why didn't the car start before I changed the fuel filter and why did it start after I hit the pump?
It's been starting since just fine, cold start, warm start OK.
Should I change the pump or wait until the car fails to start again?
Is it the pump or something else?
The pump didn't seem to run even when I applied direct current to it, however I just read that it has an internal pressure regulator and when the pressure is high it won't run. Meaning once the system is primed but the engine doesn't fire the pump will start running until the pressure drops.
Can anyone confirm?
 
#7 ·
If you changed the fuel filter - to a Bosch/Mann fuel filter - and now it starts fine - then then problem was a failed fuel filter - which yes - has a pressure relief function - a "common" failure seen here in US with non-MB/Bosch/Mann fuel filters and very/very common to China and Indonesian off-brand fuel filter replacements here.
 
#9 · (Edited)
If you changed the fuel filter - to a Bosch/Mann fuel filter - and now it starts fine - then then problem was a failed fuel filter.......
and

The pump has contaminants in the housing, and the pumps life span is done! More importantly, even though the pump appears to be operating for the moment, likely the Volume and Pressure are below spec!
.
.
As mentioned the pump is week the rap with the hammer it a temperate fix, this pump is completely unreliable, period!
Patch
Therein lies the problem, has the no-start issue been fixed by changing the filter or do I need to shell out for a new pump (so far I have used only OEM parts for any repair and maintenance, including filter changes)?
 
#8 · (Edited)
"However, the no-start condition shouldn't have been caused by a clogged filter" These filters play an important role in the proper operation of the fuel delivery system! Not only can they make the engine hard to start, but may also cause lean conditions and reduce throttle response!

"and me whacking the pump shouldn't have made the pump work and the car start either." The pump has contaminants in the housing, and the pumps life span is done! More importantly, even though the pump appears to be operating for the moment, likely the Volume and Pressure are below spec!

"So then why didn't the car start before I changed the fuel filter and why did it start after I hit the pump?" As mentioned the pump is week the rap with the hammer it a temporary fix, this pump is completely unreliable, period!

As for "direct current" for clarification prepossess, the systems on the car are all DC "Direct Currant"
We do know what you are referring to however, "Direct to The Pump"- that is a simple bypass and can be helpful when trouble shooting the system.

The question you need to ask is, if you want to risk a towing charge to the cost of the pump replacement?
The Filter you would have replaced when replacing the pump, that was not wasted time or money!

Patch
 
#10 ·
Dacia, From half way around the world, experience says, the pump is finished!

To be sure you would need to perform a pressure and volume tests.

Because you had to rap the "pump" with a hammer to make the "pump" run, it is just a matter of time now before it will fail.

Yes you need a pump.

Patch
 
#11 · (Edited)
Well, I got a fairly cheap Bosch pump, $160 shipped, and the car is running again.
I have to say I am very disappointed that the fuel pump went at less than 120K miles.

This car has left me stranded (or semi-stranded with the CPS problem) twice already and I had to change engine mounts, control arm bushing and MAF sensor at barely 60K miles. The navigation system and TV died years ago, the CD changer is barely working, the roof liner is sagging, the brake lamp was wonky for a while until I re-soldered it, I changed the brake switch at 80K, the headlamps are yellow again after I sanded them down 4 years ago, water pump was changed at 90K, etc, etc.

Seems like my two W124s were much better, I highly doubt that this car would make it even close to the miles I got out of those cars (well over 200K miles on both of them).
I just hope that it is true that Mercedes has improved the quality of their cars again from 2010.

My friend's Toyota has over 130K on it and he hasn't done much to it other than putting gas in it.

I am not impressed by the quality of this 210, not to mention the wife's A160.
On that one the belt tentioner was changed at 45K, and now at 70K the starter is going, which will cost me another $1,000 as I can't drop the engine on my driveway to replace it. The steering rack has been clicking since day one (I bought the thing used with 20K on it), the driver's side window doesn't go up more then 4 inches at each button push, etc.

Piece of shites if you ask me.

I will give Mercedes one more try at a 2012 W212 but if that one doesn't work out bye bye Benz, the Germans make other fine cars.

Thanks for the help everyone.

I forgot, I just ordered engine mounts for the wife's car, they are gone.
At 70K.
What a joke.
 
#12 ·
Comparing the models, bare in mind that W124 was the last mechanical model coming from 100 years of experience.
W210 is first digital model coming from only short experience MB had on S class.
Early CPS and MAF did fail at high rate, but once you update them, they usually last.
Wait till you get newer models. On our 11 years old W211 parts are falling off while standing. :)
Still comparing a car with 10 sensors vs one with 100 sensors is not quite fair.
 
#14 ·
Well, I kinda disagree with this assessment.
My 1993 W124 did have a MAF sensor and it lasted until about 120K.
The 210 has a lot of mechanical problems including the infamous spring perch issue, the disintegrating harmonic balancer, breaking rear window regulators, failing engine mounts, etc. etc. the list is quite long. Mercedes has been making cars for over 100 years, surely they have gotten the hang of the mechanical part by now.
Or should have anyway.
I will steer clear of the 211 for the "falling parts" problem you mentioned, funny that, and just hope that the 212 is really improved, as that is what I have read.

Dacia?

"I have to say I am very disappointed that the fuel pump went at less than 120K miles."

It's not the mileage; it's the years! Let's take a minute to think about.
120,000K over 15 years, 8,000 average per year, or 5,000 miles. The car sits a lot, the pump gathers or accumulates fine debris through the tank the gas in the pump breaks down, in short it clogs the pump. If you only burn a tank a month why not use a stabilizer when you fuel up? This could help the complete fuel system, all the way to the injectors which experience the same conditions?

"headlamps are yellow again after I sanded them down 4 years ago,"
I've seen this complaint many times. I redid mine 3 years ago, and just this winter I redid them to match the clear coat I used, so they now "sparkle" literately! But I did not need to refinish them this year, I chose to! You must of used the wrong clear 4 years ago? Would you prefer the value of a glass beam over these?

"the brake lamp was wonky for a while until I re-soldered it,"
I am curious about this fix.

I think most not all are because the car is under used.
You are sure about the starter?

Patch
I am not sure why the fuel pump failed, you may be correct in your assessment.
I go through about two tank of gas a month, lot of city driving involved.
The need to sand the headlights again is because I couldn't find the proper UV protecting solution here in Japan when I did it the first time and the sun is very strong (I changed the parking position though and now park with the back towards the morning sun).
The break lamp fix was at the left socket housing where the bulbs go.
If you take it out and examine it you'll see that the contacts are not very strong and some are lose so a bit of solder help to make them stronger.

About the wife's car's starter, I changed the battery two weeks ago.
The old one was over five years old and as she didn't drive it often enough to give it good charging it was failing.
With the new battery the car often times doesn't turn over at the first try (the problem started last year with the old battery).
When I turn the key all the lights come on, then I hear a click (sometimes not even that) and nothing happens.
I try again and usually at the second or third try it fires up.
I researched it and it seems a lot of the W168s have this problem, the car has less than 70K on it, it is 11 years old.
I asked for the price of the starter relay, it would cost me about $80 here in Japan,
The starter is installed at the top of the engine and the clearance is not enough to remove with the engine in place so it needs to be lowered.
It would cost me about $1,000 to have it replaced, including the price of a rebuilt starter, which Yanase (the only dealer in Japan) charges $500 for. Crazy.
But then again all of their prices are crazy, one spark plug costs 3,300 yen, about $30, the fuel pump would have set me back 60,000 yen, about $600.
 
#13 ·
Dacia?

"I have to say I am very disappointed that the fuel pump went at less than 120K miles."

It's not the mileage; it's the years! Let's take a minute to think about.
120,000K over 15 years, 8,000 average per year, or 5,000 miles. The car sits a lot, the pump gathers or accumulates fine debris through the tank the gas in the pump breaks down, in short it clogs the pump. If you only burn a tank a month why not use a stabilizer when you fuel up? This could help the complete fuel system, all the way to the injectors which experience the same conditions?

"headlamps are yellow again after I sanded them down 4 years ago,"
I've seen this complaint many times. I redid mine 3 years ago, and just this winter I redid them to match the clear coat I used, so they now "sparkle" literately! But I did not need to refinish them this year, I chose to! You must of used the wrong clear 4 years ago? Would you prefer the value of a glass beam over these?

"the brake lamp was wonky for a while until I re-soldered it,"
I am curious about this fix.

I think most not all are because the car is under used.
You are sure about the starter?

Patch
 
#15 ·
Thanks for sharing that information Dacia, I have a better idea of your frustration now.

I had the described problem with my passenger side brake light some years back.

After you get the pump changed I would likely add some injector treatment to deal with cleaning the rest of the fuel system. Based on what we discussed, would likely do so for a couple of tanks. I don't use the stuff so not comfortable recommending one over the other, perhaps Kaj can suggest something?

If I not mistaken there is a law regarding how many miles/KLM a vehicle may have to be road worthy in japan? We have a low mileage import from there, a 90 MR2.

Patch
 
#16 ·
M.B.'s post 2007 are much better manufactured cars.
Post update 2007 W211's had a lot of bugs ironed out.
Skip the W203 altogether and just get a W204 if you are in that market.

Of course the diesel injectors up to 2012 are still cause of problems however many German and European cars suffer this issue.

The real issues with ALL contemporary cars will be with the electronics and computerization.
Redundant components firmware and software will render these cars too expensive to fix or impossible to fix without bodging.

I owned a Japanese W124. It was a grey import to my country.
The bodywork and interior were immaculate and had less than 80,000 miles when I bought it.

The 80,000 miles was subjective.
Many Asian cars sit in traffic all day, rarely go above 40km's per hour and suffer constant stop start traffic with the AC working.
Also many suffer the "Garage Queen" syndrome - only driven at weekends.

I spent a lot of money on that car. From changing the transmission all cooling components, AC components, Rubber hoses and vacuum pipes, Fuel pumps etc etc etc.

The age of the car and the no/slow driving syndrome created the problem.
 
#17 ·
"The real issues with ALL contemporary cars will be with the electronics and computerization.
Redundant components firmware and software will render these cars too expensive to fix or impossible to fix without bodging."

I don't want to hijack the thread, so will leave this one comment to address this one quot above, and with respect and courtesy intended...

Ivan, This paragraph took me by surprise! I've given it some thought; I get the choice of words, however I disagree with the inevitable conclusion!

I will agree that MB will continue to develop much higher performance technology as will other leading manufacturers. This will not detract from those that wish to own and maintain or modify older models from any number of decades or brands. I don't believe "bodging" is relative to most older model owners serious about maintaining the classics as a daily or weekend driven.

Patch
 
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