Hi-

I have a 2002 C320.

On Monday, after driving most of the day, I parked my car for about 30 minutes. When I tried to restart, the battery seemed to be engaging, but the engine wouldn't start. I tried again, and the engine started. The "check engine" light came on and stayed on for a while. I should also say, I was in the fuel zone where my reserve malfunction showed. I went to the gas station and filled up. The "check engine" light did not come on.

On Wednesday, the same thing happened, exactly...gas level very similar to Monday (reserve fuel level).

On Friday, the same thing happened. This time, I had half a tank of gas, but it still wouldn't start. I tried for 20 minutes and was unsuccessful. So, I disconnected the negative terminal of the battery and waited 30 minutes. The car started and ran for 2 hours on the highway, but as soon as I idled at a stop sign, it died. I disconnected the negative terminal again and waited 10 minutes. It started. No engine light appeared this time.

I'm at a loss as to what is wrong. I use 87 unleaded...might be the culprit on Monday & Wednesday?? I have 80K miles. No malfunctions appear.

I drive for a living and need to figure this out quickly...thanks for any and all input/ideas/advice.

Angie

 

Get a code reader and get us the code and also put only 91 or 93 in the car they tend to like it better. but using 87 would not cause this issue. Could be a cps which is a common issue. also add your location so we may better help you.

 

Just to clarify, is the car cranking over and not starting, or is it not even cranking the engine over?

 

Thanks, and I'll fill up with a higher grade gasoline. Also, I'm going to the auto store to ask them to figure out codes.
I added my location...MS.

 

It is cranking but not starting. Two different people who were going to jump start the car said the battery was fine but it just wasn't starting for some reason.

 

Replace the CPS (Crankshaft Position Sensor) Post any stored codes.

 

Ok. Just found a CPS for $54.99 at Autozone. Thanks, and I'll post codes.

 

One other question. When last did the car have a fuel filter?. Check fuel pressure on the front injector rail. You will see a pressure point on the fuel rail with a protective cap screwed over it. Autozone or similar can loan you a tester.

 

I would buy the genuine CPS from RMeuropean, Parts.com etc. Not expensive. I would be surprised if Autozone had the genuine unit but I might be wrong.

 

Autozone has a brand called BWG. They couldn't get their computer to attach to my input, so I don't have any codes. The guy I took it to for the actual work couldn't figure out how to even get to the CPS. So, I have to wait until Monday and take it to an import mechanic. Ugh!

 

Instead of starting a new thread, I'd like to just add in my starting issue I've been having.

Every now and again, usually if I don't start the car for a day, I will go to turn the car on and it will crank and the engine will start but it chugs a bit and dies after 1 or 2 seconds. After I try the second time, it works. What could this be? I don't have any check engine lights or anything on (besides SRS light but that's been on for a while).

 

My engine light usually shows up for a while with this issue.

 

The CPS is down the back of the engine on the drivers side (USA) - A SOB to get to but easier on a M112 engine than the Quadcam M272.

It is held in place with one 7mm torx bolt.


Number 5 in diag.

 

Hi, a late reply, not too late i hope so :-)
Got the same car as your i.e. 2002 C320. Had simmilar problem i.e. late starting. Merc techs inspected and said its the fuel pump that weak. Changed the same but still no change. Again got inspection done and they found a faulty fuel injector. Changed that and thank God car starting has been fine since then.
Adding fuel injector cleaner to your fuel can also help if the injector clogging problem is not severe. Good luck.