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You should really get it investigated by SDS... rail pressure limit for injection permission is about 200 bar, you can get actual reading of both crank and cam sensors etc,

injector wrong coding does not prevent car to start, but may cause bad idle, noise etc.

Check all injector connectors (pins contacting for sure)

are injectors brand new, refurbished or just 2nd hand? In two latter case measure injector leak back while cranking.
 

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2005 Mercedes-Benz E320
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I have a problem with starting on my w211 E320 08. Car is cranking but no start. I removed glow plugs and I checked, they heat up very nice. I put them back again. I though to check the voltage on each of them at the beginning comes 12.5 and after one second stops at 3.8 and stays like that. I did change module control and the same situation. Any one have any idea what is going on? Thanks 😊
I had the same problem on my 2005 E320. It would crank but not start. Car was not out of gas. I believe I had an error code which pointed to the crankshaft position sensor. Unit cost about $45.00 and I was able to replace myself. Its location id on the driver side near the firewall, but in the bell housing. Here's a link to a youtube video which shows how to replace >>>
 

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Discussion Starter #24
Thank you
I did change crankshaft p sensor.

Injectors are used,only 50k mikes from trusted buyer. How I understand pressure is going maximum because has not enough power on both injectors and glow plugs.
Something looks wrong with electricity because when I locate the key at position 2 and I check voltage on glow plugs,at the first show 12.5 volt and in a second drop at 4.8 volt. I did change module injectors control too.
I don’t think that is normal.
 

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Forgot the glow plugs and control module, it does not prevent your car to start. You may have lower voltage glow plugs anyway (some models do have).

'Enough power for both injectors and glow' is wrong thought... 'pressure goes maximum' does not tell anything, what is 'maximum'? System max pressure is around 2000-2500 bar I believe you have no such gauge?

LP pump delivers fuel to HP pump, pressure is there under 10 bar. HP pump delivers fuel to rail, and pressure there goes 150-250 bar at cranking. Only after pressure limit is reached, ECU start injecting fuel. If there is leak somewhere, crank rpm is not enough to build required pressure. Thats why we need exact reading of the pressure during crankin to rule out pressure problem.

At idle pressure is kept at couple hundred bars. Pressure is ECU controlled by pressure valve (end of the rail) and fuel quantity valve (next to hp pump). Faulty fuel temp sensor or pressure sensor can prevent starting too. Pressure sensor can be 'diagnosed' by unplugging it at starting. ECU ignores pressure limit and gives injection command, is real pressure in rail is enough, car will start at limp mode.

If pressure in cranking is ok, next direction is electrical.

Edit: Like above said crank sensor is common culprit, but you need to check out also cam sensor (front of the engine), because crank sensor need to be sync at start. Fault code would tell if tehre is problems with either of sensors
 

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Discussion Starter #26
Thank you Mersum1es
Make sense everything.
I have another question. Is any other valve somewhere which can effect the car to not start,because when I put the key at position 2 pump start working and has good pressure after filter and is holding pressure before I crank,but when I connect another gauge at rail is not showing nothing at position 2! I think this is not normal,because for my opinion pressure valve is not getting right pressure to send information at ECU and that’s why I think power drops in a second. Any other valve somewhere for holdin pressure on rail,or some other issues effects this situation?
 

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Discussion Starter #27
Forgot the glow plugs and control module, it does not prevent your car to start. You may have lower voltage glow plugs anyway (some models do have).

'Enough power for both injectors and glow' is wrong thought... 'pressure goes maximum' does not tell anything, what is 'maximum'? System max pressure is around 2000-2500 bar I believe you have no such gauge?

LP pump delivers fuel to HP pump, pressure is there under 10 bar. HP pump delivers fuel to rail, and pressure there goes 150-250 bar at cranking. Only after pressure limit is reached, ECU start injecting fuel. If there is leak somewhere, crank rpm is not enough to build required pressure. Thats why we need exact reading of the pressure during crankin to rule out pressure problem.

At idle pressure is kept at couple hundred bars. Pressure is ECU controlled by pressure valve (end of the rail) and fuel quantity valve (next to hp pump). Faulty fuel temp sensor or pressure sensor can prevent starting too. Pressure sensor can be 'diagnosed' by unplugging it at starting. ECU ignores pressure limit and gives injection command, is real pressure in rail is enough, car will start at limp mode.

If pressure in cranking is ok, next direction is electrical.

Edit: Like above said crank sensor is common culprit, but you need to check out also cam sensor (front of the engine), because crank sensor need to be sync at start. Fault code would tell if tehre is problems with either of sensors
Glow plugs are fine because I checked,and those are not heating up with 4.8 volt because I did checked 2 of them outside of Engine when the voltage drops. That time glow plugs didn’t heated up. I think pressure on rail influence electric system to drop like that. Is there another valve that I should look at? Rail is not holding pressure at position 2
 

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Discussion Starter #28
Glow plugs are fine because I checked,and those are not heating up with 4.8 volt because I did checked 2 of them outside of Engine when the voltage drops. That time glow plugs didn’t heated up. I think pressure on rail influence electric system to drop like that. Is there another valve that I should look at? Rail is not holding pressure at position 2
Control module was changed too. I forgot to say that.
 

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rail pressure DOES NOT influence electric to drop down voltage... so again; you crank and BATTERY voltage drops 5V????? It means your battery is bad.
 

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Discussion Starter #30
Control module was changed too. I forgot to say that.
I can’t see camshaft at this engine e320 bluetec. I have another one Ml350 08 and I see has 2 camshaft in front of engine. Does this model has camshafts?
 

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Discussion Starter #31
rail pressure DOES NOT influence electric to drop down voltage... so again; you crank and BATTERY voltage drops 5V????? It means your battery is bad.
I don’t think so,because battery is new and also I keep jumping with other car when I work on car.
 

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Discussion Starter #32
I don’t think so,because battery is new and also I keep jumping with other car when I work on car.
Power drops only on glow plugs and injectors because I checked with other voltmeter on alternator and there stays around 12 during crank.
 

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Discussion Starter #34
Power drops only on glow plugs and injectors because I checked with other voltmeter on alternator and there stays around 12 during crank.
also power on glow plugs and injectors drop before I start cranking too. It stays only a second around 12 volt and drop at around 5 v
 

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also power on glow plugs and injectors drop before I start cranking too. It stays only a second around 12 volt and drop at around 5 v
With 7V plugs, that's how it suppose to work, not sure about correct voltage thought.
You flood your own topic too much. Making it hard to understand. Did you get rail pressure numbers?
 

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Discussion Starter #36
Hi there
I finally started my car,but has vary bad idle and shows all glow plugs bad, but I checked them outside and those are fine. Can someone help me on this situation?
 

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You may have the wrong type of glow plugs most likely. You need the 7V type. I believe NGK part number is 9970.
You need to check your fuel rail pressure.
 

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Discussion Starter #38
I don’t think are glow plugs the problem,because it has bad idle also when car goes 80 grad Celsius too.
 

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wrong injectors, wrong injector coding, leaky injectors (yes I know reputable source but still measuring the tank leak is pretty fast)...

Does engine run smoothly when revving up? Any difference in idle if gear is P/N/RD?

Sadly without any diagnosing data we are just guessing here...
 
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