Thanks for the input, but I've had the cover off again recently, and the screws are definitely tight on mine. I can't wait for the fuel to get low again so I can see if it's really related to fuel level like I suspect.

 

you could get one of those cheap gas siphon/pumps from your local auto parts store and a 5 gallon can or two and troubleshoot it much quicker. empty and fill at your convenience.

 

Is there anyone here that has the Comptech SC without these problems?

I am leaning towards the SC but if both have major issues, I may reconsider.

 

[QUOTE]Originally posted by modifry
[B]Thanks for the input, but I've had the cover off again recently, and the screws are definitely tight on mine.

 

Well, I ran it down to 1.3 gallons (typical for me) and only noticed a very slight increase in the humming sound, nothing like it has done before. I let the car run while I fueled up, and sat in the car and listened. If the noise changed at all, it wasn't by much. It was barely audible when the tank was empty, so it was hard to tell.

But later that night, it decided to give me a medium-intensity whine for one short trip, then shut up again.

hecash - thanks for the assurances, it does help knowing it's probably not a functional defect. I can live with it at the low or medium sound level I have heard this week, hopefully the outrageous noise from a few weeks ago will not return.

As for the fuel smell - I can't believe how bad it is sometimes. I parked outside for 5 hours yesterday and when I came back to the car I could smell gas from 5 feet away. I will definitely have to spend some time this weekend checking all the fittings again - last weekend I didn't get a chance, too busy making my first batch of the new infra-red Dash Control Interface to send Lucid. The new one works with Kenwood, Alpine, Pioneer and Clarion, as well as those Sony HU's with IR-only(except the new ones with the high-speed computer IR interface).

 

[QUOTE]Originally posted by modifry
[B]Well, I ran it down to 1.3 gallons (typical for me) and only noticed a very slight increase in the humming sound, nothing like it has done before.

 

yup all large fuel pumps that I have owned make a pretty loud buzz or whine. I dont think its anything you should worry about

 

[QUOTE]Originally posted by modifry
[B]It's a new SC, purchased from 4IGS2000 (at a great price too) and I received it the beginning of December.

 

Thanks, I will probably add some more to the web page later, especially if I get my problems fixed.

I got different results with the fuel pump noise the next time the fuel got low. At about 1/4 to 1/3 tank it started humming slightly, so I played with it a little. At first I thought it varied in intensity with ON/OFF throttle, but then I figured out it was the gas sloshing to one side (or front/back) that made the noise change.

I then ran it down to fill up time (no bars lit) and when I pulled off the Interstate it was making a louder noise. Not like the first few times, but definitely there. Annoying if you were stopped or driving slow, but hardly noticeable at highway speeds.

Anyway, I made a video with my Canon S230, which is posted here on the S2000 Atlanta site (it's an 8MB AVI). You have to crank your volume up all the way to hear it, evidently the camera mic is not that great. If you listen carefully, at around 15 seconds into the video the noise gets a little louder and changes pitch (don't know why), so I then put the camera under the car, and you should definitely hear the noise then.

When I filled up, I left the engine running, and this time, the noise stopped when I put 3 gallons into the tank (out of 11.5 total). So at this point I'm convinced it's fuel pump, and it makes more noise when there is no fuel to dampen the vibrations.

I'm too busy this weekend to play with it more, maybe next week. I'm considering pulling the fuel pump and running it in a bucket of fuel (no fire hazard here, Officer) to see if I can get it to hum. If I can, I may try to mechanically dampen the vibrations with rubber (fuel hose) or added mass.

 

it is the fuel pump. It is going to be loud. Yes it may get annoying but you are going to have to live with it, unless you get a inline pump or two.