C240 W203 Crank But Won't Start - Going Crazy...
07-11-2019, 06:44 PM
#1
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C240 W203 Crank But Won't Start - Going Crazy...
Crank But Won't Start - Going Crazy...
Apology guys, I had to start a new thread on this topic since others are a bit old.
My car C240; W203; 2002; Odometer reading: 205,000 miles. Next A Service, at least 5,000 miles.
Last week without warning the car stuttered on the freeway, started to stall. I cleared to the shoulder, the car failed completely. It cranked but refused to start. Warning light displayed alternator not charging. So I towed car home. Jump-started with powerful battery charger, car cranked but still refused to start. Here is a timeline of parts I replaced:
1. New alternator replacement - 2 and half years ago (professional installation)
2. Replaced Crankshaft Position Sensor (Bosch) - exactly 1 yr ago - from Amazon
3. Replaced Serpentine belt - exactly 1 yr ago
4. Replaced Belt Tensioner - exactly 1 yr ago
5. Replaced Belt Idler Pulley - exactly 1 yr ago
6. Replaced all 12 spark plugs (Bosch) - 4 yrs ago (Average 7k miles/year since replacement)
After car failed on freeway last week, I did the following:
1. Checked alternator, pulleys, belt tensioner, battery, all ok - last week
2. Replaced serpentine belt again, anyway - last week
3. Cleaned MAF sensor with professional MAF sensor cleaner - last week
4. Installed new Fuel Pump - yesterday
5. Tested Schrader valve with Injection Pump Pressure Tester, passed at 55-60psi - tested yesterday.
I should mention here that car initially did not start even with new fuel pump, until I added more fuel to tank from 1/8 to quarter tank. Fuel pump tester also showed zero pressure reading before I added more fuel.
Car started today, I drove only three miles, car sputtered and died again in front of Walmart. Crank pretty good but no start. Towed car home again, second time in one week. Here's what I did today when I got home:
1. Tested Schrader valve with pump tester, zero pressure reading.
2. Poured small quantity of gas directly into MAF sensor opening, car started, ran for a few seconds, then cut out.
3. At ignition position 2, fuel pump initiates for a few seconds, then stops.
I am at my wits end. What is the problem? Car is too old to take to dealership and spend gazillion dollars. I did everything above by myself, except alternator replacement done by a certified Benz mechanic. I bought iCarsoft MBII OBD scanner and scanned for codes, but I'm still learning this scanner and can't decipher the numerous codes. There's no code specifically for fuel system, or at least I can't tell. How do I test or read fuel-related codes on this gizmo?.
Can anyone tell me what's going on with the car? Much appreciated, thanks!. So so, sorry for the very long post.
Apology guys, I had to start a new thread on this topic since others are a bit old.
My car C240; W203; 2002; Odometer reading: 205,000 miles. Next A Service, at least 5,000 miles.
Last week without warning the car stuttered on the freeway, started to stall. I cleared to the shoulder, the car failed completely. It cranked but refused to start. Warning light displayed alternator not charging. So I towed car home. Jump-started with powerful battery charger, car cranked but still refused to start. Here is a timeline of parts I replaced:
1. New alternator replacement - 2 and half years ago (professional installation)
2. Replaced Crankshaft Position Sensor (Bosch) - exactly 1 yr ago - from Amazon
3. Replaced Serpentine belt - exactly 1 yr ago
4. Replaced Belt Tensioner - exactly 1 yr ago
5. Replaced Belt Idler Pulley - exactly 1 yr ago
6. Replaced all 12 spark plugs (Bosch) - 4 yrs ago (Average 7k miles/year since replacement)
After car failed on freeway last week, I did the following:
1. Checked alternator, pulleys, belt tensioner, battery, all ok - last week
2. Replaced serpentine belt again, anyway - last week
3. Cleaned MAF sensor with professional MAF sensor cleaner - last week
4. Installed new Fuel Pump - yesterday
5. Tested Schrader valve with Injection Pump Pressure Tester, passed at 55-60psi - tested yesterday.
I should mention here that car initially did not start even with new fuel pump, until I added more fuel to tank from 1/8 to quarter tank. Fuel pump tester also showed zero pressure reading before I added more fuel.
Car started today, I drove only three miles, car sputtered and died again in front of Walmart. Crank pretty good but no start. Towed car home again, second time in one week. Here's what I did today when I got home:
1. Tested Schrader valve with pump tester, zero pressure reading.
2. Poured small quantity of gas directly into MAF sensor opening, car started, ran for a few seconds, then cut out.
3. At ignition position 2, fuel pump initiates for a few seconds, then stops.
I am at my wits end. What is the problem? Car is too old to take to dealership and spend gazillion dollars. I did everything above by myself, except alternator replacement done by a certified Benz mechanic. I bought iCarsoft MBII OBD scanner and scanned for codes, but I'm still learning this scanner and can't decipher the numerous codes. There's no code specifically for fuel system, or at least I can't tell. How do I test or read fuel-related codes on this gizmo?.
Can anyone tell me what's going on with the car? Much appreciated, thanks!. So so, sorry for the very long post.
07-12-2019, 06:04 AM
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2003 C230K Coupe Orion Blue
Try priming the fuel pump (turn to position 2). The no fuel pressure part seems to point to the fuel pump circuit.
Did you get an OEM or Bosch unit?
When replacing the pump, did you make sure both houses were plugged in properly, such that they clicked into place? I just replaced mine the other day and the fitment is really tight on those hoses.
Did you fill up the tank? Wondering if you have some large air pocket in the fuel line between the filter and motor.
The circuit has a fuse, relay, and pump itself. Did you check the fuse and test the relay?
Did you get an OEM or Bosch unit?
When replacing the pump, did you make sure both houses were plugged in properly, such that they clicked into place? I just replaced mine the other day and the fitment is really tight on those hoses.
Did you fill up the tank? Wondering if you have some large air pocket in the fuel line between the filter and motor.
The circuit has a fuse, relay, and pump itself. Did you check the fuse and test the relay?
Last edited by slammer111; 07-12-2019 at 06:06 AM.
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Merlin1935 (07-12-2019)
07-12-2019, 11:44 AM
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Thread Starter
Try priming the fuel pump (turn to position 2). The no fuel pressure part seems to point to the fuel pump circuit.
Did you get an OEM or Bosch unit?
When replacing the pump, did you make sure both houses were plugged in properly, such that they clicked into place? I just replaced mine the other day and the fitment is really tight on those hoses.
Did you fill up the tank? Wondering if you have some large air pocket in the fuel line between the filter and motor.
The circuit has a fuse, relay, and pump itself. Did you check the fuse and test the relay?
Did you get an OEM or Bosch unit?
When replacing the pump, did you make sure both houses were plugged in properly, such that they clicked into place? I just replaced mine the other day and the fitment is really tight on those hoses.
Did you fill up the tank? Wondering if you have some large air pocket in the fuel line between the filter and motor.
The circuit has a fuse, relay, and pump itself. Did you check the fuse and test the relay?
New pump is Herko, not Bosch. Both hoses are pushed in to their limits. What brand is your new pump?
I never had a chance to fill up the tank after pump replacement - car died shortly after I drove out with new pump.
Fuse is ok, how do I locate and test circuit and relay?
Thanks!
07-12-2019, 01:42 PM
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2003 C230K Coupe Orion Blue
My new pump is a Bosch. Can't comment much on the Herko, but it almost sounds like your new pump died. Are you sure you can hear it priming, or is it the sound of say a seized pump which can also make a buzzing noise?
Check your manual or that folded piece of paper behind the steering wheel for the relay location. The relay should be in the rear of the car. My coupe may be different from your sedan in terms of exact location. With that said, if you're hearing a buzzing noise from the pump, it's getting juice. Therefore the problem is not with the relay.
To test a relay, apply 12V to the input pins and check the output pins for continuity (the relay should "click" and close, completing the circuit). The job requires a multimeter and some wires with alligator clips. A 12V power supply helps, but I just used my car battery to provide the juice.
Check your manual or that folded piece of paper behind the steering wheel for the relay location. The relay should be in the rear of the car. My coupe may be different from your sedan in terms of exact location. With that said, if you're hearing a buzzing noise from the pump, it's getting juice. Therefore the problem is not with the relay.
To test a relay, apply 12V to the input pins and check the output pins for continuity (the relay should "click" and close, completing the circuit). The job requires a multimeter and some wires with alligator clips. A 12V power supply helps, but I just used my car battery to provide the juice.
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Merlin1935 (07-13-2019)
07-18-2019, 12:03 AM
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w203 , w204
The other little thing to check is to see if the internal fuel transfer line is working.
I have seen a few of these either perish or dislodge in the tank.
Simply, fill the tank to over 3/4 full and see if the car runs if the car starts to play up at under 1/3 full then I would be looking at the transfer line for a hole or still connected at both ends of it.
Craig
I have seen a few of these either perish or dislodge in the tank.
Simply, fill the tank to over 3/4 full and see if the car runs if the car starts to play up at under 1/3 full then I would be looking at the transfer line for a hole or still connected at both ends of it.
Craig
07-21-2019, 01:40 PM
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Beer never tasted so good...
It was fuel pump.
The Bosch replacement arrived, one look at it I kinda sensed it would solve the problem. It fitted easily without force, hoses clicked all the way in, unlike aftermarket brand. Car started easily at first crank for the first time in two weeks. Pump pressure test passed. Test drive... car had never accelerated so smoothly in a long time. I guess the other things I did while searching for a solution helped to improve performance - new fuel filter, air filter and MAF sensor cleaning.
Although it showed similar symptoms to CPS, in the end it was a defective fuel pump, and it got confusing when I initially installed aftermarket brand. Lesson learned, never install aftermarket parts for critical systems.
Thanks for all your help, folks.
It was fuel pump.
The Bosch replacement arrived, one look at it I kinda sensed it would solve the problem. It fitted easily without force, hoses clicked all the way in, unlike aftermarket brand. Car started easily at first crank for the first time in two weeks. Pump pressure test passed. Test drive... car had never accelerated so smoothly in a long time. I guess the other things I did while searching for a solution helped to improve performance - new fuel filter, air filter and MAF sensor cleaning.
Although it showed similar symptoms to CPS, in the end it was a defective fuel pump, and it got confusing when I initially installed aftermarket brand. Lesson learned, never install aftermarket parts for critical systems.
Thanks for all your help, folks.
