2002 ml320 dies after start...is not key
Hello everybody and I hope you can help:
2002 ML 320
213,000 miles
Week 1: It took about 2 to 3 seconds of cranking my engine for the car to start.
(note: the car would always start up immediately after it had been running but take the additional seconds after it had sit for 3 minutes or more)
Week 2. About 3-5 seconds
Changed Crank Shaft Position Sensor (Autozone Part) still the same problem.
Week 3: A starter cycle and a half to start
At the end of the week after getting off the expressway after 30 minutes of driving and after passing through 2000rpms to 1500rpms the engine died. Restarted immediately and died again on the next exit. I had to tow it home at that point as it would not restart.
I have had no CE lights
I just changed my fuel pump to no avail. The fuel filter was changed about 65,000 miles ago and I think I am good on this. I have about 15-20lbs psi of fuel pressure before i crank the engine and have key in position 2. I have a guage hooked up to the schraeder valve on the fuel rail. When i turn the ignition to position 2 i easily hear the fuel pump power up and hear fuel rushing through the lines (I haven't re-installed the pump access panel or seat yet so I can hear this quite easily). After about 2-3 seconds the pump shuts off even though the key is still in position 2. I try to start and it acts like its going too but it doesn't. I watch the fuel pressure gauge during crank and it shows renewed pressure again of about 15-20lbs. I have measured my pressure before while the engine is running and it measures at about 60lbs psi. I started measuring fuel pressure just today and my battery is low and I am assuming the lower pressure readings would be because my batter is low? I am charging my battery tonight with a battery charger and will watch pressure again tomorrow morning. It seems to me an electric fuel pump would produce the same amount of pressure regardless if the engine is running or not?
I also listened and felt the fuel pump relay opening and closing both during key position two and during crank. I also switched out relays with another relay (rear window heater) which was exactly the same relay to test it. It seemed like it was working fine then too.
A couple of times out of the 15 times i tried to restart after installing the pump the engine started up and ran just fine for the 3-5 seconds it stayed on. I think this should rule out any coil pack/sparkplug or wire problems. I would think I would definitely get a light on this also don't you think?
Something else weird i noticed. I checked to make sure the CPS elec connector was seated properly. It was but I noticed after taking it off the cannon plug rotated 360 degrees numerous times in the same direction. It seems like maybe this plug is not wired directly but maybe has some type of magnetic connection also???? If not this might be the actual problem. I will check this out further tomorrow morning also.
I recently changed my alternator with an autozone alternator and i am going to take that off tomorrow morning and get it tested just to rule this out. I dont think this is the problem though.
Please post any and all crazy or hair brained ideas if you have them. I am willing to try anything.
I was a Blackhawk Helicopter Crewchief for ten years in the US Army and love to work on my own car. Of course I am no vehicle mechanic so please don't take this super long post as arrogant. I am just trying to be as specific as possible. Thanks again for your help!!
Hello everybody and I hope you can help:
2002 ML 320
213,000 miles
Week 1: It took about 2 to 3 seconds of cranking my engine for the car to start.
(note: the car would always start up immediately after it had been running but take the additional seconds after it had sit for 3 minutes or more)
Week 2. About 3-5 seconds
Changed Crank Shaft Position Sensor (Autozone Part) still the same problem.
Week 3: A starter cycle and a half to start
At the end of the week after getting off the expressway after 30 minutes of driving and after passing through 2000rpms to 1500rpms the engine died. Restarted immediately and died again on the next exit. I had to tow it home at that point as it would not restart.
I have had no CE lights
I just changed my fuel pump to no avail. The fuel filter was changed about 65,000 miles ago and I think I am good on this. I have about 15-20lbs psi of fuel pressure before i crank the engine and have key in position 2. I have a guage hooked up to the schraeder valve on the fuel rail. When i turn the ignition to position 2 i easily hear the fuel pump power up and hear fuel rushing through the lines (I haven't re-installed the pump access panel or seat yet so I can hear this quite easily). After about 2-3 seconds the pump shuts off even though the key is still in position 2. I try to start and it acts like its going too but it doesn't. I watch the fuel pressure gauge during crank and it shows renewed pressure again of about 15-20lbs. I have measured my pressure before while the engine is running and it measures at about 60lbs psi. I started measuring fuel pressure just today and my battery is low and I am assuming the lower pressure readings would be because my batter is low? I am charging my battery tonight with a battery charger and will watch pressure again tomorrow morning. It seems to me an electric fuel pump would produce the same amount of pressure regardless if the engine is running or not?
I also listened and felt the fuel pump relay opening and closing both during key position two and during crank. I also switched out relays with another relay (rear window heater) which was exactly the same relay to test it. It seemed like it was working fine then too.
A couple of times out of the 15 times i tried to restart after installing the pump the engine started up and ran just fine for the 3-5 seconds it stayed on. I think this should rule out any coil pack/sparkplug or wire problems. I would think I would definitely get a light on this also don't you think?
Something else weird i noticed. I checked to make sure the CPS elec connector was seated properly. It was but I noticed after taking it off the cannon plug rotated 360 degrees numerous times in the same direction. It seems like maybe this plug is not wired directly but maybe has some type of magnetic connection also???? If not this might be the actual problem. I will check this out further tomorrow morning also.
I recently changed my alternator with an autozone alternator and i am going to take that off tomorrow morning and get it tested just to rule this out. I dont think this is the problem though.
Please post any and all crazy or hair brained ideas if you have them. I am willing to try anything.
I was a Blackhawk Helicopter Crewchief for ten years in the US Army and love to work on my own car. Of course I am no vehicle mechanic so please don't take this super long post as arrogant. I am just trying to be as specific as possible. Thanks again for your help!!
Newbie
I have the same problem with my 2000 ML320. I have changed the CPS twice, the mechanic changed it also along with the Fuel Pump and the Fuel Filter. Still have the same problem.
Junior Member
I know it's been a couple of months, but it's too bad the thread didn't go anywhere, i.e. what was wrong after all. I am currently having a problem which apparently may be that the voltage regulator in the alternator has gone bad (alternator is surely messed-up though), battery light on, the car quits after only a minute or less of idling even though the battery is all charged. Malfunctioning alternator can give out higher voltage during acceleration or even idling, which would cause the truck to shut down to avoid electric damage. So I wonder if anything like this was the problem in this case, or just a bad CPS? CPS is really what first comes to mind.
