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2004 C240 mercedes wagon

Hi—I am getting the run around and I feel like walking--------when I start my car with smartkey it seems to hesitate a little before it catches…some times its fine like when the mechanic turned it 30 times and it worked perfectly. I have heard maybe full pump—then battery which is good then ignition switch but i made an appointment with the dealer instead because everyone that says they work on mercedes really dont. I actually suggested the ignition but hey im a babe in the woods who likes the beach. No one even test drove it or checked wires —just listened . Quoting things like well my friend can do it for 750.00 if its the switch but its a chance…also quoted maybe a thousand if its the switch . if if if …can this be a smart key battery problem? Before I go to benz on monday I want to change the smark key battery it is after all 8 years old. what do you think? I want to trade it in for a toyota really…thank you!!!

What do you mean with it “hesitating a little before it catches”?
If you mean that the starter turns, does it then take 30 times to get it started?
Once it starts, can you restart it and it will run immediately?
If so, it could be related to the fuel line not being primed among one possibility of what’s going on.

Btw, I’m no expert on Mercedes but a car is a car so let’s start at the basics.

it hesitates like a ticking sound for a few seconds and starts ----it never stalled. sometimes it just starts fine without any hesitation like when the mechanic tried it. I meant every time he tried it it worked fine…then I would leave and it would happen…one mechanic heard it and said maybe fuel pump…then the one who tried it 30 times finally heard it but then said maybe ignition switch… and said why dont you see my friend at merecedes around the corner–you know their all connected

the starter turns perfect but sometimes makes a hesitation before it catches --I wish I can make the sound so you would understand LOL

but what you are saying is what the first mechanic said but he didnt call back because he wasnt sure and he didnt want to change fuel pump if it wasnt the problem --he is not a benz mechanic

remco what do you mean by being primed? the first guy wanted to replace the fuel pump but I know he felt a little nervous ----------i heard this car had 2 fuel pumps …wow do I feel like a babe right now

Don’t feel bad. Cars aren’t everyone’s cuppa tea.

it hesitates like a ticking sound for a few seconds and starts

So does the starter seem to turn the engine over or do you just hear a click and after a while it will turn the engine over?

actually it kind of sounds like a rev not sure how to explain as if you think its going to stall and then it works…it happened in the parking lot at the gym and there were guys outside and they looked at the car as if it something was wrong but then it caught and worked fine…went down a few blocks to mechanic and he turned the key and it worked perfect…over and over again it worked perfect…

Could you perhaps take a video of it with your phone, post it to utube and link it here?

this mechanic seemed to busy really to be bothered he had so many cars–the other day I left it with him all day while I went into town and when I came back he hadnt looked at it yet–so to pacify me he put in a new battery and told me to drive around to see if that was the problem —i told him that my battery was fairly new a year and half and I paid 350 dollars for it and didnt want his battery but he insisted …needless to say it started up fine and then when I went to start this morning it happened again brought it back to him and he put my old battery back in …

I will try but it doesnt happen all the time and I would have to have someone with me as I turn the key so they can hold the phone and hope it happens-------I will ask someone with patience lol

It is just difficult for us to tell what’s wrong like this.
The starter turns normally when this happens but it doesn’t want to start and acts like it wants to stall when it does finally start.
If that’s a basic description, it could be that the fuel line is not getting primed properly. Before you start a car, it needs to have the proper pressure going to the fuel injectors. It does that by running the pump very briefly, basically sending some fuel down before you start it. It is just enough to have the car start and get it running.
If that doesn’t happen, the car will not start correctly. It is called ‘priming’.

Try this: turn the key to the position just before the start position. Turn it back off and then do it again, going to the position just before the start position.
If it is quiet, you should hear this very slight ‘whirr’ coming from the trunk area. It may last for about a second or so each time.
It could very well be that the car will start now, if you try this procedure a couple of times. Maybe it primes but the pressure isn’t quite good enough to start. Doing it several times may mask the problem and help you start it.
Regardless, it buys us a clue.

Edit: also, have you ever seen the car do this after it had just been driven? Like maybe you went to the store, did your thing for a half hour, tried to start it and it failed. Or maybe it never failed like that. Maybe it only fails when you leave it for hours at a time or overnight?
Whether it never or sometimes happens is another possible clue.

It is just difficult for us to tell what’s wrong like this.
The starter turns normally when this happens but it doesn’t want to start and acts like it wants to stall when it does finally start. you basically summed it up exactly —I took an hour class at gym and it made that sound as if its going to stop as if the battery might not be great but then catches —so if figured its doing it now so let me go 10 minutes down the road to the mechanic and it worked fine for him ( I laughed out of nerves)…but when I left it for a while one of the guys said when he moved my car he heard it…

first mechanic who I went to said it sounded like fuel pump but then back away from job—because he doenst work on mercedes and I think he felt responsible since we know someone mutual…the rest of the guys I went to were saying things like --go to my friend so and so I told him on the phone what is sounds like and they said tell her 750.00 for ingnition switch but we cant be sure–so I said yeah right

mercedes wont even listen to you unless you put it on there diagnostic machine starting at 130.00 then they will tell you what they think —and then I will tell them what I think which is do you have a toyota

their

You’re right in not having anyone throw parts at the car. It will be expensive and most likely wrong.

Try what I suggested and see if it helps at all. If so and you can reliably start it 100 percent of the time, you may decide to live with it.
Where are you located? If Oregon, I have a friend there that works on nothing but Mercedes.

I havent driven it since 430 today so I am going to try and see what it does now—its 11 10 —

so I just went to my car and it did the stall noise thing and started --then I turned it off pulled out the key did it again and then it made the sound slightly —I turned the car off without pulling out the key and turned it to the right slow not all the way then back again and then and again like you said and for the next three tries it started perfectly.

im in new york :frowning: