Hello everyone. Well, I have a 2001 ML320 that just started taking several seconds of cranking before it finally starts. Its seems to happen after it sits a while, but will start right back up if you shut it off and try to restart it to replicate the problem. And because of the automatic starting dealio, if you remove your hand from cranking the key, it keeps cranking until it finally starts. But once, it cranked for a little bit of a longer time, so it stopped trying to crank by it self. Once it starts, though, its fine. No misfire, no dying while running or driving. Replaced the CPS, no luck.

I have read through the thread with some similar problems, but most had more severe starting and running issues as well. And most were older MLs.

Any ideas??

Thanks.

Had hard starting issues for months with my 99 ML320. When it finally died suddenly on the road, it was the fuel pump and the MAS. Not sure which one triggered the other to fail, but I did get a CE light for months that I chose to ignore. I believe the MAS would have set that off.

My first thought would have been the CPS too.

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2009 ML350 (106K) - Family vehicle
2001 CLK430 Cabriolet (80K) - Wife's car
2005 BMW 645CI (138K) - My daily driver
2016 Mustang (32K) - Daughter's car

No, no check engine light on yet and if it was the MAFS, it wouldn't run right after it started. Maybe the fuel pump is getting weak? The truck has 75k miles on it.

The fuel filter is the KEY to a quick restart.

Both the fuel pressure regulator & check valve are built into the filter.

Is the filter original??

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Not sure if it is or not.

What do you think about this post regarding a bad relay #12?? :

"In January I read a post about putting the ignition into position 2 and waiting for the instrument lights to light up (1-2 seconds) and then starting the car. I tried this when it was 24 degrees out and the car started with no problems. The guys in the forum suggested that this was a bad fuel pum and that the fuel rails had to pressurize before the car would start properly. The truck still wouldnt start if I tried to start it normally from a cold start.

I found out through this forum that I could solve this problem by swapping relay #12 with another relay like #26. If the truck started then I had my answer. I purchased a new relay for $15 bucks and the car now starts on the first try even in below freezing temperatures. It was 19 degrees last week and the ML started with no problems on the first try. It has started every day since then with no problems."

Does this make sense to try??

Ok, well, just replaced the fuel filter yesterday and so far, so good. No problems in 2 days. So looks like that was the fix. Thanks Doc.!

MBDOC,
Just passing some feedback on your post from 2007- you saved the day for me. I have a 2001 ML320- puchased from RBM in Atlanta. Had truck service before I left atlanta. Drove to San Antonio. It had 20K miles on the feul filter at the time of the problem. I brought it to MB San Antonio who coould not recreate the problem. Based on your post- I asked them to replace the feul filter. And amazing- the truck starts right up every time. So- you still got it! and thank you. Here is your post: