ML320 Will not Start Stalls - update on symptoms
 

In the past two weeks. Refused to start 4 times. Then would start 30-60 Minutes later. (Engine turns over just fine-no fire)

IT does not stumble it eithr runs or not. I ran it up to 90 MPH to do a laymans test of gas flow. All went fine.

Twice it stalled at intersections ..thankfully it started back up both times.

I have a 1999 with 100,000. Today I checked underneath and I have the origional style fuel Filter so I checked the pressure a few times when it would start and when it would not and there was pressure.

But today I heard a clue. It would not start in my garage. I raised the hood - after cranking but with the key still on I hear noises. There is a sound kind of high pitch like an electric motor running at the back of the intake manifold as far as I can tell. In addition a couple times there was in addition a gurggle.

Also included in this demonic possession is - I was under the hood and the doors locked. I didnt touch a thing. Both keys were inside the vehical. Thankfully a window was down. Have not a clue if it is related.

So What gizmo could buzz/whine with the engine off and key on that effects running ? (yes my fan was shut off).

Well the ESP light came on because you disconnected the battery. When you hooked it up the steering angle sensor wasn't initialized. Driving it initialized it and the light went off.

The two common, non security, reasons for not starting are the fuel pump on unmodified versions and the crank sensor.

You'll love the fuel pump update if you haven't had it done, yet. Go in to buy a fuel pump, and they'll tell you you need 4 other parts (3 lines and fuel filter) to make it work, because MB saw fit to re-design this fuel pump problem of theirs.

It's not the fuel pump that got redesigned, it's the fuel pressure regulator...which is integrated in the fuel filter.

My fuel pump died over Memorial Day weekend in the middle of Podunck USA. The out-of-town dealership had to order all sorts of connections to do the retrofit, but unfortunately, some of the parts were backordered. So I had to let them replace the pump and put the old filter and parts back in...so I'm STILL looking at having to do the retrofit down the road... :(

ahhhh, that would make more sense... I always send the retrofit out to the dealer, because of liability reasons. They never were clear as to what was the reason for the retrofit.

Only real way I know is to check fuel pressure...mine was 0 psi at failure.

Also, the fuel pump on the ML isn't nicely tucked in front of the rear tire (like the other MB models) but buried in the tank. And access to the filter and pump (for retrofit purposes) requires the removal of the rear seat and the panel underneath. The service manager took me to where the tech was working on mine and I got a visual of what was involved.

All I can say is...enjoy yourself! ;)

MB has dropped the price of the pump recently and make it one of the better deals in pumps.

ml320 continued
 

3 questions.

1) How much pressure should there be in the fuel system ?

2) how is it measured ? A fuel pressure guage while running ?

3) should there be a buzz under the hood with the engine not running and the key on ? (cold engine).

Update Sept 9th

I read 1) about 55 LBS
2) fuel pressure guage
3) buzzing in air intake hose not uncomon.
I replaced my Fuel filter and lines. It was a snap. (a 3 hour snap) So far so good, no stalling . started 6 for 6.