hey guys.

so the story first.

Woke up one morning to go to school, started the car, and it was an obvious misfire.

turned it right off. chilled for a cigarette, started it again and everything ran smoothly.

I did not think anything of it.
2 days later, same thing. Car had a misfire. I unplugged the battery waited 15 minutes and car ran smoothly again.

My first thought is spark plugs + wires.

So i ordered those so I can change them out. They are due either way.

Now my car will not start.
I tried resetting it a couple times.
It just keeps cranking. Sometimes it starts for a couple seconds.. (running like a bag of crap) and just dies down.

I did some research which indicated that my CPS could be faulty.

So i went ahead and replaced the CPS sensor. The problem is still there.
I am still waiting for my spark plugs and wires to arrive.

I also jumped the fuel pump relay and the pump stays ON. sounds like the pump is running fine.

In the meantime what else could i possibly do/check to narrow down the problem?

Sounds like your MAF sensors out.

C32 doesn't have a MAF sensor.

Get the CEL reset and swap the coil packs around and try again. See if the misfires move with the coil packs.

Do you have a scan tool? (like a cheap Autel one) It will hopefully pull a code.
Also is the CPS OEM? (Bosch 0261210170) Some of the aftermarket are apparently duds. i can remember when my car died(one of many) it was the alternator have you checked that out? You can check the voltage through comand system: "In comand in aux position press 1&3 for a few seconds, then you will see a list. I think that then you go to Info or diagnostic to see the current voltage"
Maybe lift the back seat and when the idle dies you will be able to clearly hear if the fuel pump is in fact failing as there are two pumps. Some additional info (https://mbworld.org/forums/c32-amg-c...p-c32-amg.html)
Hope some of this helps. I feel ya: mine is back on the blocks again awaiting another IC pump and the verdict of why there is abit of black sludge in the coolant res, umm i wonder... head gasket, or intercooler, cracked head....not looking forward to this mystery being solved.

I will try swapping around the coil packs.
Hopefully my cables and plugs arrive today so I can swap those out too.

I have no scan tool. But if you recommend me one I will go and pick it up. It will be useful in the future.
I will check the cps sensor. I'm pretty sure it's not OEM. But I will check that out again.

The Voltage seems fine. When I try to start it I also connect it to the charger.

I have the cheapest version (about $100) of this brand : http://www.autelshop.com/

there are a couple of threads on scan tools somewhere : https://mbworld.org/forums/showthread.php?p=4848237

But I think this is the pick for various reasons http://www.drewtech.com/enthusiast/i...hydashdaq.html

I will check these out when I get home from college.

UPDATE: the car started yesterday and worked for a bit. Had no problems starting.
This morning though when I was leaving for school. Tried to start it and it died out again within a couple seconds.

I noticed the only times it didn't start was early in the morning. When it is cold.
I'm not sure if this has anything to do with it. But I'm suspecting it does.

UPDATE: I picked up the original CPS from Mercedes and installed it.
After that the car starts no problem.

I believe the aftermarket sensor i got was a knock-off.

Still awaiting wires and plugs to come.

if you still have a problem after the OEM cps, check fuel pressure - even though pump is running, doesn't mean it has sufficient fuel pressure

I was thinking it could be the fuel pump
how can i check the fuel pressure.

the only question in my mind how can the fuel pressure change. because when the car is running its running completely fine.. no hesitation no loss in power.

UPDATE:

I changed the CPS sensor, I changed the spark plugs and the wires. I also changed the fuel pump relay and fuse.

I found my problem, my fuel pump is sticking.....

Sometimes it will work sometimes it wont.
I hit it lightly with a hammer and it works again.

Weird..

It would be much appreciated if people gave input on possible options if this problem is fixable or replaceable.

Mercedes-Benz gave me a quote of 2200.00 for just the parts. thats the pump and the unit on the other side.

Link on 4th post mate, (Failed Fuel Pump - C32 AMG).

Well to tell you the truth. Now I am confused.

I believed it was the pump.
But the pump hasn't gotten stuck for a week + now.

So I have a brand new pump on the way.

It's ****ing with my mind.

Could be the fuel pump sending unit which is next to the fuel pump

I doubt it.
After replacing the spark plugs, wires and the CPS.
The pump was sticking for a couple days.

I had to hit it lightly for it to unstick.
Had to do this 3 or 4 times a day. Usually before starting it.
Before doing so I always tried to start the car first.
Now it has been over a week probably close to two that there was no need for hitting the pump.

When last was the fuel filter changed?

Im not sure, I will be changing it when I receive the pump.

Might have been when i first got the car.
At 87000 Kilometers. I am at 150xxx right now.

Were you able to fix this? Im having the same issue. I get no codes and the car wont start.

Hey,

Yes the issue has been resolved.
It turned out to be just the pump.
It was sticking so sometimes it worked and sometimes it didn't.

Try hitting it with a rubber hammer. its behind the passenger seat. under the seat.


I ordered the pump that someone linked in this post.

Everything is back to normal.

The only thing is i had to get a special tool for the big nut.

The tool was $150.00 i found it through a local shop.

let me know if you need any more information i can help out as much as possible