1999 E320 4MATIC Wagon Stalling - PeachParts Mercedes-Benz Forum

sleepysan · #1 07-21-2008, 12:18 PM

New to this forum and am hoping someone has been through this already. I've searched most of the posts and haven't found the same exact problem.

We have a 1999 E320 Wagon 4Matic and has been running beautifully for years. However, recently the car stalled while driving and would not start again. We waited a few minutes and the car started up. That was about a month ago and the car had been fine up until now. Now, every day, the car will run for about 10 blocks or 20 minutes and stall out, same deal.. wait and it starts up again. The problem is getting worse, and the length of time to wait is now about 30 minutes. Others on this forum have posted similar stalls, but we have had no check engine light. We've done the oil change, checked the fluids, etc.. all fine. We bought the fuel filter to replace, but haven't found where it is on the driver's side.

Recently, we changed the sparks and just now, the battery. I assume that it is temperature related and some sensor is going off preventing further driving. I don't think it's a fuel problem, we only use 93 and there is no hesitation. Side notes, the A/C runs frigid, radio/CD, headlights, all stay on after the engine stall.

I'd rather not have a parts roulette and hope for the best. Does anyone know what's up, or what the next part I should replace? I was looking for an OVP and Crank Position Sensor that another post suggested, but again, we never and still don't have a check engine light.

The last random thing is that I cannot reproduce the stall in my driveway. In our last 95degree heatwave, I let it run with the a/c blasting for 25 minutes and no stall. Maybe I have just not waited long enough, or it is something else.

Thanks in advance for any of your help! I'd like to DIY versus taking it to the dealer.

jcyuhn · #2 07-21-2008, 01:10 PM

You need a crank position sensor (CPS).

TMAllison · #3 07-21-2008, 01:37 PM

You don't have an OVP; you do have a K40 relay which serves the same function.

Sounds pretty classic for the CPS. Is on the left side, top of the trans bell housing.

sleepysan · #4 07-21-2008, 01:51 PM

Thanks jcyuhn and TMAllison. Would I have a CPS problem even with no Check Engine light? Anyone have a diagram or access to a photo of where it is. I have seen the part in pictures, but when I look under the hood, I don't see it or don't realize it's right there in front of me.

TMAllison, do you think I need to change out the K40 relay as well?

TMAllison · #5 07-21-2008, 02:00 PM

Prob no on the K40....the CPS is usually on the left (drivers side) on top of the trans bell housing where the trans attaches to the engine. Peak down between rear of engine and firewall; use a flashlight. On my diesel the oil filter obscures your vision of that area.

sleepysan · #6 07-21-2008, 03:47 PM

Where to buy a cps and would anyone know if it is a single or double?

TMAllison · #7 07-21-2008, 04:04 PM

BUY PARTS tab above is what supports the forum.....