MORE ISSUES......
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From: Virginia
MORE ISSUES......
Ok, I'm about ready to take a fork and knife and cut the C4S into pieces....
Over the weekend I posted about the car "surging" in revs but NOT developing any power...particularly noticeable between 3000-4000 on tach. The revs would drop then pick back up....all this occuring while on throttle !!!
I ran thru the battery of tests suggested by Steve Weiner and Kelly Kim...
https://rennlist.com/forums/993-forum/187047-help-power-surge-then-drop-in-rpms.html
All electronic devices appear to be working fine and the clutch slipping tests didn't result in over revs....
Now, over the last week I've noticed a "humming" noise coming from behind the dash....today it was VERY pronounced. So I lift the hood and can hear this loud "humming/buzzing" noise coming from the fuel tank....directly below the fuse box there is small tube entering the tank and man this thing is singing a song....really does not sound good at all.
Fuel Pump.... right ?? Starting to let go.....right ? Causing fuel delivery problems resulting in the car "surging" in revs with no power......RIGHT ???????
WTF IS GOIN' ON ?????
Over the weekend I posted about the car "surging" in revs but NOT developing any power...particularly noticeable between 3000-4000 on tach. The revs would drop then pick back up....all this occuring while on throttle !!!
I ran thru the battery of tests suggested by Steve Weiner and Kelly Kim...
https://rennlist.com/forums/993-forum/187047-help-power-surge-then-drop-in-rpms.html
All electronic devices appear to be working fine and the clutch slipping tests didn't result in over revs....
Now, over the last week I've noticed a "humming" noise coming from behind the dash....today it was VERY pronounced. So I lift the hood and can hear this loud "humming/buzzing" noise coming from the fuel tank....directly below the fuse box there is small tube entering the tank and man this thing is singing a song....really does not sound good at all.
Fuel Pump.... right ?? Starting to let go.....right ? Causing fuel delivery problems resulting in the car "surging" in revs with no power......RIGHT ???????
WTF IS GOIN' ON ?????
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From: yorba linda, ca
I would agree, sometimes swear words help
Does this humming sound occur when the key is on, engine off? Maybe it is the fuel pump. If this humming does happen with the key on, engine off, try [turn-off key first] removing the fuel pump fuse and try it again, key on, engine off. Seems as though fuel pump failures are rare in the 993, but you never know..
Good luck!
Does this humming sound occur when the key is on, engine off? Maybe it is the fuel pump. If this humming does happen with the key on, engine off, try [turn-off key first] removing the fuel pump fuse and try it again, key on, engine off. Seems as though fuel pump failures are rare in the 993, but you never know..
Good luck!
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From: Kauai, Hawaii
Keith,
I examined my car and looked for anything buzzing in that general area. When I first turn the key, there is a loud buzzing noise for about a second or two that can be heard from inside the car when starting it. Buzzing disappears with car running. With the car running I put my ear close to the fuse box area and can hear a whirring, slightly buzzing noise coming from the component in the picture. Accoring to the PET, this is the tank gauge.
Sorry, but I can't tell where the fuel pump is located from just looking at the PET. Perhaps someone here can tell you where it is located.
Is the buzzing loud enough that you can hear it from inside the car?
I examined my car and looked for anything buzzing in that general area. When I first turn the key, there is a loud buzzing noise for about a second or two that can be heard from inside the car when starting it. Buzzing disappears with car running. With the car running I put my ear close to the fuse box area and can hear a whirring, slightly buzzing noise coming from the component in the picture. Accoring to the PET, this is the tank gauge.
Sorry, but I can't tell where the fuel pump is located from just looking at the PET. Perhaps someone here can tell you where it is located.
Is the buzzing loud enough that you can hear it from inside the car?
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From: Virginia
Yeah, you can hear it inside the car. It's loud enough to drown out the RSR's at idle !! It is not the same buzzing you hear when the ignition key is turned on.
It's beyond the scope of me being able to fix it anyway....dealer will look at this week. Be curious to see what the outcome is .....
It's beyond the scope of me being able to fix it anyway....dealer will look at this week. Be curious to see what the outcome is .....
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Keith,
Humming/buzzing fuel pump is not abnormal, but if it gets loud enough that you can hear it inside the cabin while driving, then it is an indication that the pump is going south sooner than later. How many miles do you have?
I had the same surging problem on an older 911 and it was caused from...I think the throttle meter? Take a look in that direction....good luck!
----------------------
'97 Blk/Blk C2S
Humming/buzzing fuel pump is not abnormal, but if it gets loud enough that you can hear it inside the cabin while driving, then it is an indication that the pump is going south sooner than later. How many miles do you have?
I had the same surging problem on an older 911 and it was caused from...I think the throttle meter? Take a look in that direction....good luck!
----------------------
'97 Blk/Blk C2S
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From: USVI
Originally Posted by kkim
Sorry, but I can't tell where the fuel pump is located from just looking at the PET. Perhaps someone here can tell you where it is located.
If you are ever working in the trunk and drop something behind the fuel tank (washers, nuts, screws, pens, etc.) whatever you drop will end up next to the fuel pump so don't bother trying to fish something out just pull the fuel pump shield from underneath the car.To check your fuel pump you can hook up a pressure gauge to the threaded connection on the fuel rail in the engine compartment and then jumper the DME relay. There is a step-by-step posted here on the forums.
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From: Virginia
Originally Posted by 911
I have the same problem, Keith. Let me know what you find out. Thanks.
Rich
Rich
Another 993 misbehavin' huh ? A C4S no less. The car is in for review Monday morning at the dealer Rich, I'll let you know what they come up with.