1993 300E car cranked but not start.
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1993 300E
1993 300E car cranked but not start.
Hi, I have a 1993 300E. My problem is that the car will crank but would not start.
I checked the green color fuel pump relay behind the battery. The fuel is good.
I listenedfor the clicking sound of the motor for the fuel pump when you turn the key to the "ON" position. No clicking sound.
My car has 2 fuel pump under the car. Just can't believe that both fuel pump are not working.
Wondering if my problem is just a simple fuel filter change.
I do notice before that when I tried to go uphill, my car does not have much power.
Is that a sign and symptom of the fuel pump going bad?
I checked the green color fuel pump relay behind the battery. The fuel is good.
I listenedfor the clicking sound of the motor for the fuel pump when you turn the key to the "ON" position. No clicking sound.
My car has 2 fuel pump under the car. Just can't believe that both fuel pump are not working.
Wondering if my problem is just a simple fuel filter change.
I do notice before that when I tried to go uphill, my car does not have much power.
Is that a sign and symptom of the fuel pump going bad?
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Joined: May 2005
Posts: 2,494
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From: REHOBOTH BEACH DE
88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
Hi, I have a 1993 300E. My problem is that the car will crank but would not start.
I checked the green color fuel pump relay behind the battery. The fuel is good.
I listenedfor the clicking sound of the motor for the fuel pump when you turn the key to the "ON" position. No clicking sound.
My car has 2 fuel pump under the car. Just can't believe that both fuel pump are not working.
Wondering if my problem is just a simple fuel filter change.
I do notice before that when I tried to go uphill, my car does not have much power.
Is that a sign and symptom of the fuel pump going bad?
I checked the green color fuel pump relay behind the battery. The fuel is good.
I listenedfor the clicking sound of the motor for the fuel pump when you turn the key to the "ON" position. No clicking sound.
My car has 2 fuel pump under the car. Just can't believe that both fuel pump are not working.
Wondering if my problem is just a simple fuel filter change.
I do notice before that when I tried to go uphill, my car does not have much power.
Is that a sign and symptom of the fuel pump going bad?
It will have either one or two fuses on the top of the relay.
See if the fuses are blown and replace if so.
If not blown then remove the relay and shake it..if it rattles it's more then likely not functioning.
Either the FPR or OVP will give the symptoms you describe !
Ed A.
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1993 300E
I check the fuse and it is good. It is a 30 amp fuse.
I thought that if the fuse is good and not blown, then the fuel pump relay(the green color relay behind the battery) must be good.
I did not try to shake it to see if it rattles.
What is FPR and OVP?
Thanks.
I thought that if the fuse is good and not blown, then the fuel pump relay(the green color relay behind the battery) must be good.
I did not try to shake it to see if it rattles.
What is FPR and OVP?
Thanks.
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1993 300E
I changed my fuel pump and actually found that my previous fuel pump is actually working. I checked my old fuel pump by connecting the fuel pump terminal with a wire directly to the battery. You get this loud "whispering" sound from the fuel pump. I also changed the fuel pump relay located behind the battery(the 30 amp fuel is good). I turned the car to "on" position and heard the "Whispering" sound from fuel pump for a moment and then it stopped. Turned car on again and now I do not hear any "whispering" sound from the fuel pump anymore. It seems that no power is getting to the fuel pump.
The car cranked but would not start. Sound the same before I even change the fuel pump relay or the fuel pump.
Anyone know what I should do next? Please advice. Thank you.
The car cranked but would not start. Sound the same before I even change the fuel pump relay or the fuel pump.
Anyone know what I should do next? Please advice. Thank you.
MBWorld Fanatic!
Joined: May 2005
Posts: 2,494
Likes: 17
From: REHOBOTH BEACH DE
88-300CE TWIN TURBO, 99-C43, 05-G55K, 71-280SL, 94-E320 CAB, 08 CLK63 BLACK SERIES
The fuel pumps ran with a direct battery connection?
If so the only thing in between the pump and the 12VDC is the FPR...
Are you getting 12VDC to energize the FPR?
Pull the relay out and jumper jack 7 ( terminal 87 ) and jack 8 ( terminal 30 )..
The pumps should run continuously..
If not see if you have 12VDC across jack 8 ( terminal 30 ) and jack 11 ( terminal 31 )
If you don't read 12VDC, then you must check the circuit out.
With the ignition on you should have 12VDC from jack 9 ( terminal 15 ) to jack 11 ( terminal 31 )
If you don't have 12VDC then you have to check the circuit out.
More tests depending how these go....
If so the only thing in between the pump and the 12VDC is the FPR...
Are you getting 12VDC to energize the FPR?
Pull the relay out and jumper jack 7 ( terminal 87 ) and jack 8 ( terminal 30 )..
The pumps should run continuously..
If not see if you have 12VDC across jack 8 ( terminal 30 ) and jack 11 ( terminal 31 )
If you don't read 12VDC, then you must check the circuit out.
With the ignition on you should have 12VDC from jack 9 ( terminal 15 ) to jack 11 ( terminal 31 )
If you don't have 12VDC then you have to check the circuit out.
More tests depending how these go....
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1993 300E
Thank for the quick response.
Q. The fuel pumps ran with a direct battery connection?
A. Yes, the disconnected old fuel pump start "whispering" loudly and actually pump out fuel from the fuel filter when connected with a wire directly to the battery. The fuel pumps works with a direct battery connection.
Q. If so the only thing in between the pump and the 12VDC is the FPR...
Are you getting 12VDC to energize the FPR?
A. I replaced the FPR ( fuel pump relay) with a new one. The 30 Amp fuel on top of it is still good. However, i just went ahead and change a new one. I am not sure if I am getting 12VDC to energize the FPR.
I can check that with a volt meter right?
Q.Pull the relay out and jumper jack 7 ( terminal 87 ) and jack 8 ( terminal 30 )..
The pumps should run continuously..
If not see if you have 12VDC across jack 8 ( terminal 30 ) and jack 11 ( terminal 31 )
If you don't read 12VDC, then you must check the circuit out.
With the ignition on you should have 12VDC from jack 9 ( terminal 15 ) to jack 11 ( terminal 31 )
If you don't have 12VDC then you have to check the circuit out.
A. I don't know what is jumper jack 7 (terminal 87 ) and jack 8 (terminal 30) and so on....I don't know where they are located and what they mean and how to test it. Pls advice . Thanks.
Where is the circuit located?
Q. The fuel pumps ran with a direct battery connection?
A. Yes, the disconnected old fuel pump start "whispering" loudly and actually pump out fuel from the fuel filter when connected with a wire directly to the battery. The fuel pumps works with a direct battery connection.
Q. If so the only thing in between the pump and the 12VDC is the FPR...
Are you getting 12VDC to energize the FPR?
A. I replaced the FPR ( fuel pump relay) with a new one. The 30 Amp fuel on top of it is still good. However, i just went ahead and change a new one. I am not sure if I am getting 12VDC to energize the FPR.
I can check that with a volt meter right?
Q.Pull the relay out and jumper jack 7 ( terminal 87 ) and jack 8 ( terminal 30 )..
The pumps should run continuously..
If not see if you have 12VDC across jack 8 ( terminal 30 ) and jack 11 ( terminal 31 )
If you don't read 12VDC, then you must check the circuit out.
With the ignition on you should have 12VDC from jack 9 ( terminal 15 ) to jack 11 ( terminal 31 )
If you don't have 12VDC then you have to check the circuit out.
A. I don't know what is jumper jack 7 (terminal 87 ) and jack 8 (terminal 30) and so on....I don't know where they are located and what they mean and how to test it. Pls advice . Thanks.
Where is the circuit located?
