Hi everyone,

I wonder if someone can point me in the right direction on this one. 2005 C 240, has the crankshaft position sensor replaced about a year ago, car has been running fine.

Yesterday I replaced the air filters , put the air intake box back on the car, making sure it was fitting snugly over the MAF sensor intake, etc. Started the car up, and everything sounded great. Took it for a drive around the block, went back and parked it and shut the engine off.


Then I remembered that usually when I make changes or do some work on the car I do that trick where you reset the ECU/transmission. You know, key to position 2, put the pedal down, key off, release the pedal, wait a few minutes until you hear a click. I must’ve done a couple of dozen times over the last five or so years but I’ve had the car and never had a problem.

Although this time after doing the procedure turning the key off and then going to start the car now it is cranking and not starting! You can hold the key and it’ll just keep cranking and never start. I immediately plugged in the scanner, and it is not showing any codes. I am not getting a check engine light, no codes. When it was my position sensor last year and I couldn’t start the car It immediately started throwing out an error code. But this time the OBD II is saying everything is a ok.

I tried pulling off the air filter section, And checked around to see if maybe I had not anything loose or damaged anything, everything looks good there are no broken hoses or frayed connections or anything. On a whim I checked in the trunk to see if the fuse for the fuel pump had somehow blown, but it looks fine. I tried the ECU reset a couple more times, and even tried disconnecting the battery for a minute. No dice. It’s exactly the same, everything lights up normally you go to crank the car and it just cranks and never starts, no check engine light and no codes.

I’ve run out of ideas! Has anyone ever run into something like this? Help!