Intermittent Start problem
 

Hi folks.

The car is a US-market 1999 C280.

In the last three weeks, this car has failed to start 3 times. We insert the key, the key turns, and the engine cranks over full speed, but no start. Wait about 5 minutes and it fires up as normal.

This doesn't happen when the engine is cold (first start of the day), it always seems to start fine when cold. If we drive it a short distance, and then let it sit for about 10-30 minutes, that's when it seems to malfunction. So when the problem occurs is when the engine is warm, and after a short rest. For example: we'll start the car cold, drive a few minutes to the market and then park. When we return about 20 minutes alter, this is the time it will act up if it's going to.

If we wait for awhile (5 minutes or so) after it fails to start, it will start right back up as if nothing is wrong.

So, I've heard the crank position sensor is a problem with these cars. Do they fail in an intermittent fashion?

As an additional data point: The CEL did come on for a half-day about 2 weeks ago, and the engine started to run poorly at that time (first time in years), and then the CEL went out and the engine ran fine again, and since. The CEL is now out, and the starting problem persists.

Maybe these two issues are related? Maybe not?

Any suggestions?

thanks

RE: Intermittent Start problem
 

I am a mercedes NOOB, I just got mine a few weeks ago.
Your problem sounds like classic coolant temperature sensor problems.

You can get one of those scan tools to read the code that triggered the CEL. That might tell you somethingalso.

RE: Intermittent Start problem
 

try the Crankshaft position sensor. typical on these cars.

RE: Intermittent Start problem: The latest
 

OK, here's the latest: the car stalled in the middle of an intersection today, and I called AAA, and just as they were getting there (45 minutes later), the car finally started up (after many tries) so I drove it back to my place. Just before it stalled, and as I drove it back, the check-engine light came on and is now on.

I got one of those generic scan tools, and the two codes in there are:

P0173 Fuel trim malfuction, bank 2

P1747 Manufacturer Control Transmission.

Chassis221 and others have said these cars tend to have a problem with the Crank Position Sensor.

If the CPS is failing, would it trip a code? If so, would it be one of these codes?

Or, is one of these two codes indicating another problem that would cause the stalling/no start issue?

And, where exactly is the CPS on this car? Is it hard to change or easy? Any tricks to getting it out?


thanks for any help/suggestions.

RE: Intermittent Start problem
 

This is awesome 'cause I am having pretty much the same issues as what you have.

I bought a 99 C230 K a few days ago (so I don't know this car history). When I bought it, everything was okay except that the dealer told me that the ECL came on on that morning for a moment and came off shortly. I brought it to a mechanic, which I am a patron of, and I had them checked up all oils, changedengine oil, checked engine (I think the mechanics did based on engine sound, meaning they didn't use any tools) and mission, and under the body. Except for one thing that cost me about 300 dollars, everything seemed to be okay. I got my car back.

However, I tried to start the engine this morning, but it didn't work! Power on, head lights on, but the engine didn't start.I jumped to see if it was a battery issue. It was not. I tried a lot of times, but nothing happened. I called a towing truck, which towed my car to the mechanic. After the driver put it down at the mechanic, he tried to start. It worked! What the hell is going on??? One of the mechanics moved my car back to the facility. He stopped the engine there and tried to start again. It did not work again! After jacking it up, they seemed to be checking here and there, then they put it down again. One started engine, which worked fine. He kept starting and stopping repeatedly. It worked fine. They told me that it would be okay for me to take it, but Ileft it there so that they can look at it again on Monday. Actually, they didn't know what the reasons were.
I didn't see ECL coming on ever since I owned this vehicle. I just saw that an indicater (looking like a lamp with some drops next to it) coming on a few times. They came offimmediately though.

If you find any answer for this, please let me know. I will also let you know if I find something.

RE: Intermittent Start problem
 

I changed out the CPS a few days ago, erased the two codes, test-drove to make sure nothing was going to re-set a code, and so far everything is normal.

Time will tell, but so far, so good.

thanks for the responses, folks.

BTW, CPS is located upper/left of bellhousing, you can reach it from the engine compartment on top. Fairly easy swap, it took me about 20 minutes. I did have to use a long blade-type screwdriver to release one side of the plug tab (closest to engine), and was able to push the other tab one with my finger, while pulling it off.

RE: Intermittent Start problem
 

Thank you for the information.
I read your first thread again and I found what isdifferent with mine.I put the ken in. The key rotated, all power worked, butthe engine did not crank when I started. Literally when I started the engine by fully rotating the key, the engine didn't responded at all. No sound...

I am not sure if changing my CPS will solve this problem, meaning I don't knowif mine is the same problem as yours. May I ask you what the CPS does? Where did you buy it? dealer? ebay? somewhere esle? How much did you pay?

Again thanks for your information.

Hugh

RE: Intermittent Start problem
 

Hey lacruisere, I found this article. I think your problem was definitely CPS.Read this!

http://www.misterfixit.com/crnksnsr.htm

Since my engine didn't even crank, my problem might be different with yours. I need to find it out.

l had exactly rhe same problem fitted CAMSHAFT sensor from e bay for £14 took me 10 mins to fit and now starting ok once again

camshaft sensor