RickyE430

Good Evening, I am new to the site and MB. Hello to you all. I was hoping someone might have some insight into an issue I am having with my 01 E430 Sport. On occasion, once a week or so, after the car has been driven and parked for a few hours, the car will have a hard time starting. It always starts on the first try, it just takes quite a bit more turning. I had the dealership replace the battery but this didnt seem to help. The car has 57K miles and everything else seems normal. Thanks in advance for any assistance. Take care-Ricky

mleskovar

...crank position sensor. The CPS seems to be a high failure item (my belief).

E55AMG99

Stong possibility indeed!

RickyE430

Thank you for the replies. I will have it checked out and post the result. Anyone know if this is a DIY job?

mleskovar

Yes, also you can save much more if you buy it online. "The sensor is about 2" long and is inserted behind the cylinder block on the drivers side to read off the flywheel. Only about 1/2" sticks out. Basically you remove the enlectrical connector and get the right torx socket and unbolt. Access to the bolt is a little difficult as it is only just in line of sight.
Hope this helps.


Its buried at the back of the engine. Its located on top, where it reads the flywheel position. Might be best to have someone change it for you, its tricky sometimes, and usually quite hot. Just one of those things.... Sometimes they come right out, other times they fight you all the way. I believe its an E8 torx bit, a long 1/4" extension and universal, and ratchet. Pull off engine cover, climb on top of motor, reach down on the drivers side at the back of the motor. Unplug, replace." (copied from another post for a V6 but I <think> it's located the same place in the V8, don't know for sure)

The crankshaft sensor can be tested with an ohm meter, the problem is it usually only fails when its hot. It will test fine until it fails, then it will read open circuit. Trying to heat one with a torch is pretty futile also, its best to pull it out right when the engine dies, and the opportunity is rare. It might have cooled down enough by the time you have removed it and will test ok. "

RickyE430

mleskovar- Thanks for the info, definetly sounds like the issue I an having. Being that my mechanical skills are quite limited I will take to the dealer. I am fourtunate to have found a pretty reasonable (as far as I know) dealership in the Phoenix area. One more question if you don't mind, Do you think this is something that should be addressed immediatly? Any possible engine harm? Just wondering if I should take the car in Monday AM. Thanks a ton for the advice!

RickyE430

Good Afternoon All,

So I had the Crank position sensor replaced. Everything was running great then the hard start problem came back again last night. Any ideas? My service advisor at the dealership said unless they can replicate the problem they cannot diagnose it. Very annoying! Any help would be great!

mleskovar

If it's not throwing a code then anything is a guess. Try to be more specific with your explanation..."It always starts on the first try, it just takes quite a bit more turning." Does that mean it only takes one flick of the key every time? Does it sound like it's trying to start, like a cylinder(s) firing until it finally starts? Does it ever not start and time out and you need to cycle the key again? I know it may not seem like it, but consider yourself lucky that it starts everytime!

RickyE430

It will always turn over on the first try but every once in a while it doesn't fire up right away. It turns and turns then kicks in. When it does this, say once every 40 starts, it reminds me of an old truck with a carburetor trying to start in the morning. I feel like I should be pumping the gas pedal. I just had the 60K service done which included plugs and fuel filter along with changing the crank position sensor.

You are correct, I do feel fortunate that it does start every time I'm just trying to prevent getting stuck somewhere

mleskovar

My next guess would be fuel pump....not an uncommon failure item and it doesn't give failure codes that I'm aware of. I was reading in the forum where it is common for them to leak with your model.

RickyE430

Thanks for the info, much appriciated

TECHNICIAN

Check the fuel pressure leakdown. Its possible the check valve in the pump is hanging up.