View Single Post
  #1  
Old 04-10-2017, 08:08 AM
Baxterdown's Avatar
Baxterdown Baxterdown is offline
Registered User
 
Join Date: Jun 2014
Location: Fort Lauderdale, FL
Posts: 269
Need help identifying a strange stall and noise

Hi guys! I need your help identifying a strange stall and noise. Here’s the scoop.

I took my 72 280SE 4.5 out for a ride Saturday. The car had been parked in the garage for about 4 weeks. It started on the second turn (as it always does) with no problem. I drove it for about 20 minutes to a restaurant (half hour stop), then about 10 minutes to a friend’s (10 min stop), then about 30 minutes to run an errand (5 mins stop). Then, on the way home the car started stalling.

About 10 minutes into the drive home, I got to a stop light and the car started to stall. I put it on neutral quickly and gave it some gas and it recovered. But, from that point forward, whenever I got to a stop or light, the car would stall. Pressing hard on the brake and giving it a tad of gas would keep it running. And, it ran perfectly ok while moving. But the second I would let go of the gas at idle, it would stall.

The engine wasn’t overheating. The gas tank was at 3/4 full and oil pressure was good. Here’s a quick picture I took while at a stop light.



Now, onto the noise. Sometime along the drive I started to hear a noise coming from the back of the car. I had heard that noise before. But I had only heard it before when I shut down the engine. Now, typically I drive with the stereo on; I wasn’t on Saturday. So, maybe the noise has been there all along and I just hadn’t heard it before.

It’s a winding noise that would run for about 30 seconds after I shut down the engine and then would come to a stop slowly. No, it’s not the power antenna. :-) This noise is on the back of the car. Also, the noise keeps going even after I cut the power and take the key out of the ignition.

This time though, the noise kept going for almost five minutes after the engine stopped and I took the key off the ignition. I took four videos.

Here’s what you’re going to see:

Video – 01
Pointing the camera at the fuel pump (microphone is down toward the ground) from the drive’s side. As you can see, the fuel pump and filter are brand new. With that said, I don’t think it’s the fuel pump because I had heard the noise before the pump was replaced.
https://www.youtube.com/watch?v=U3j1EALJrII

Video – 02
Pointing the camera at the fuel pump from the passenger’s side (same thing, microphone toward the ground).
https://www.youtube.com/watch?v=0YRnn2_UW6E

Video – 03
Pointing the microphone at the fuel pump (camera toward the ground) from the driver’s side. You can hear the sound start to sputter here. This was about three minutes after the engine shut down. I was baffled the thing was still going!
https://www.youtube.com/watch?v=fWyUTPtrwNA

Video – 04
Camera pointing to the gas tank relief valve. The valve is brand new and you’ll notice it is different than the OEM part. The W108 valves do not exist anymore so I had to use the valve from an SL when I replaced it.
https://www.youtube.com/watch?v=hNwCsQwDEDs

A few things to keep in mind. You guys might remember I redid the undercarriage last fall. At the time, I had all fuel lines replaced. I also replaced the gas pump and filter, and gas tank relief valve as I mentioned above. The fuel sender unit is new as well. I replaced it last summer and bought the unit new from MBCC.

I showed the video to my mechanic yesterday and he thinks both the stalling and noise might have something with pressure building in the gas tank. He asked that I drive the car again and try to replicate the issue. Then when the car stalls, he asked that I remove the gas cap, check to see if it’s hard to turn, if the sound it makes is a swoosh or a pop to indicate inward or outward pressure, and see if that will alleviate the symptoms.

I'm going to wait until Saturday to take out the car again. I can only drive it after work during the week and I don't want to risk getting stuck at night.

In the meantime, please let me know what you guys think.

Thanks!

Jose
__________________
Current
1972 280SE 4.5 Dark Green, Cognac. Pics!
2014 Range Rover Sport Supercharged. Santorini Black, Dynamic Package, Front Climate Comfort and Visibility Package, Vision and Convenience Package.


Gone But Not Forgotten
2010 Explorer Limited, 2010 R350 4MATIC, 2011 Jeep Grand Cherokee Overland, 2009 Audi A4 Cabriolet, 2009 Ford Flex, 2008 Mercedes-Benz ML350, 2008 Mercedes-Benz E350, 2007 Mercedes-Benz C230, 2005 BMW X5.
Reply With Quote