MB Marko

So im sick of the issue i was going to wait for a light to come on the dash but I've had enough.

First start of the day takes a long time to catch and feels like the car is struggling more than normal.(only the first start if the car sits over night 8-9 hours+)

driving up inclines the car feels like theres no power some times.


the manual says 240,000KM for the fuel filter and 100,000KM for the injectors( not sure i forgot to double check) I'm at 140,000KM and the only things I've ever had to change was the SAP one under warranty once not, brake fluid x3, transmission fluid x2, spark plugs I did it at 120,000KM and lots of oil changes and filter changes.

I feel like its way to early for a fuel filter but my injectors have probably lived a long life.... they cost 400$CAD from rock auto the best price i could find.

you guys think I should bite the built and change them? let me know what you guys think if i can find a good price fuel filter i'd jump on it and do it early.

ItalianJoe1

Never seen an interval for changing injectors. You issue sounds like a fuel pump failing. Lift the rear seat cushions, remove the access covers, and look for signs of leakage. Then test fuel pressure when it's cold, there is a test port at the rail underhood, you should have full pressure with the key on (not starting), and after running the pressure should hold, only drop a few psi, for hours.

MB Marko

ya ill have to get a kit to test that thanks! do you know what PSI it should show?

ItalianJoe1

I'd have to look it up but it should be at least 55psi or so. What you are really looking for is the lack of pressure when starting, or rapid dropping after shutdown, or if you can keep the gauge on while driving, if it drops under load when you feel the loss of power. This all points to a clogged filter, weak pump, or failed regulator. It should be more or less steady at all times.

ChazThePhoenix

could also be sediment in the tank that settles over night. I had that on my VW. just a thought

MB Marko

Not sure i ordered a tester off amazon. I only use SHELL V Power + and never fill up if I see a tanker at the station. I don't even know where to buy a filter for these cars I took off the back seats and covers it all looks so different hahaha.

I'll have to see what is going on when the tester arrives. I hope its not sediment in the tank.....


I'll add the dealers price is about $450 each for the left and right side. they said its very uncommon to change it this early also the same with injectors. I definitely want to get this tester sooner than later!

alecmascot

First of all stop guessing and throwing money at the problem.
Get it to a skilled person with the correct diagnostic equipment. Probably not MB.
" First start of the day takes a long time to catch " is often caused by a faulty crank position sensor. It will not generate any codes.

MB Marko

your right i love to throw money around hahaha. I thought it could be the crank position sensor from reading the w203 forums its a cheap sensor anyways i might just go get it now.

alecmascot

Spend a few bucks on a iCarsoft MB-2 and you can read live data from the various sensors

ItalianJoe1

CKP causes hot restart issues, they usually work fine when cooled down. Check the fuel pressure first. That will point you in the right direction.

atraudes

It would also be useful to see how the pressure holds after stopping the car. It should hold pressure for quite a while before starting to drop off. If it drops off suddenly or quickly, that could be a clue.

Just food for thought: if you (or anyone else) ends up needing new injectors you can send them off to be flow tested and cleaned instead of buying new ones. It's not terrifically expensive (~$100 the last time I did it) though there is some down time incurred with mailing them off and waiting to get them back. You can avoid this by buying some used injectors off eBay, having them cleaned, and using those. Then theoretically you could sell your old ones for the same price you bought the others for.

I used http://fuelinjectorclinic.com/ and was happy with them.

MB Marko

my neighbour has a shop he said he will clean my injectors free, i just need to fine time to take them off that would be my first step before buying new ones.

I bought the crankshaft position sensor $40 not to bad but its a little bit of a ***** to change it out..... ill save it for tomorrow morning.

I'm still going to test the fuel pressure once I get the gauge.

We had a stint when it was 40 degrees celsius for a week straight I happened to drive a lot during that period I believe thats when the starting issue happened. I read on the w203 section people had the same issue with the crankshaft position sensor if it gets over heated it can start to fail.

MB Marko

well that wasn't fun.....


2 hours trying to change the crank position sensor I had to give up..... which is rare. they honestly put it in the worst spot of the engine you need to have toothpick forearms and baby hands if you want to get that thing off.

the T-30 seems impossible like you need to pull the engine to get it off I'm at a loss for words.... i need to find an INDY to get this **** done.

Adi-Benz

Why are c63 injectors only $190 and ours are more.

Nicholi2007

What was the issue?

MB Marko

took out the injectors had a look at them they seemed fine, I really think it was bad gas as silly as it sounds... i haven't had the issues since.

W204Motorsports

I recommend some Red Line fuel cleaner before every oil change.




I'm getting close too 300k on my 2008 C300 with stock fuel pump/filter and injectors with no issues. I use to put a little sea foam but I find that Red Line does a better job. First time I used it at around 200k, the car idled smoother and seemed to have better throttle response. I usually put half a bottle before an oil change and drive till the gas tank is empty with the red line in it before draining the oil.

superangrypenguin

The last part about draining the oil is critical. This product is AWESOME but may cause oil shearing due to contamination.

Nicholi2007

Do you add when nearing empty before refuel or does it matter? Mercedes recommends , so I'm curious on how they compare.

W204Motorsports

Techron gave the most money to Mercedes so they recommend them. Not to say Techron isn't a great product. I add the Red line when my tank is empty so as I fill up, I am sure it get's mixed in well. Pretty sure the instructions on the bottle say to do so anyways, it is only logical.

As superangrypenguin said, it is crucial to change your oil as soon as you've driven and emptied the gas tank with the cleaner because some of it will get pass the piston rings and dilute your oil, resulting in less engine lubrication.

Nicholi2007

Contamination is probably minimal but yeah that makes sense.

superangrypenguin

Minimal, but oil shearing does have a pretty significant effect. In one case, it dropped my oil's flashpoint by 50F.

For those of you with DI engines, it matters more. For those of you with traditional PFI engines, it's no big deal, but for the latter, there's really not big need to run fuel system cleaners. I ran them on my old RS4, but I have not once used fuel injector cleaner on my PFI C300.

Nicholi2007

How did you manage to measure that? Not doubting. just asking....

superangrypenguin

Used Oil Analysis by way of submitting engine oil before/after to Blackstone Labs