driveability

Hey all,
I have a 2005 CL65 I decided to swap out my fuel pump based on miles and age. I changed to filter a month prior, so I decided to try a Bosch 044, install it and it worked fine for a month than began to make ugly noises. I removed the bosch unit and installed to old unit until I could get a new replacement.
The original one seemed to work fine but it too began to make the same type of noises so I was wondering if there was something within the system binding up these units. The noise over the next day or so stopped coming from the pump (scraping noises). I then began to here a hissing noise or air type of sound coming from the tank.

Meanwhile the car runs fine, I didn't haven't checked the fuel pressure.
I wondering what the hell is going on ??? I will be removing the pump and filter to check that its installed correctly and make sure the filter / regulator is working correctly.

any thoughts ?????

BlownV8

Some of those Bosch pumps are just.loud.

driveability

Ok
Is anyone familiar with the return line to the tank ? Is it just a simple hose or is there something connected to it in the tank ? Wondering if a return filter or another dampener is involved ?

I did say/imply/suggest the pump noise was not normal so being loud isn't the issue.

driveability

SO,
I took a further look at the fuel pump and looks like the noise isn't the return line. I'm down to the vacuum line that is attached to the fuel filter.
The sound seems to travel in a odd way as we know that is just the way it is with noises often. i did check Fuel pressure and my gauge says between 60 and 70 psi. Can't know how accurate the unit is . Seems to sit a 50 key on engine off. I see there's a flow / pressure regulating valve and controller sitting next to the pump ? Emergency shut off system ? Well I should do
more research // Any info would be appreciated. Wife and I are selling our
house in Orange county ca. and moving up to the north west part of Washington state. (Whatcom county Washington ) Hope to get a bigger house and a real shop

ItalianJoe1

It may be some sort of noise caused by more fuel bypassing the regulator due to the larger pump. Hard to say without seeing it.

driveability

First of all thanks for the reply,
That's a good thought and makes sense, however I crimped off the return and the sound didn't change.I also crimped off the vacuum line and it didn't effect the sound. I need to locate the vacuum source at the engine and crimp it there to see if the sound changes. I just don't know where that line is located. I did however remember connecting the fuel pump electriclley back-wards and powered it up. I guess I could have pushed something off the tank end. Can see pushing off the tank sock/filter unless it has a check valve or something which wouldn't hold up to that type of pressure. I'm not sure there was much gas to be suck back to the tank or if the pump would even work in reverse. I guess it could have always been there. My neighbor has a S55 should be similar maybe I can listen to his car and go from there.

driveability

So
one more thing to add, I powered the pump externally and there was no
odd sound. I am narrowing things down. The system does have a vacuum line to the fuel filter and I crimped it off at the filter and that didn't stop the noise, but there are other air powered systems in the car.

Otherwise the car runs fantastic !!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
BY THE WAY THE CAR HAS 200,000 MILES ON IT !!!!!!!!!!!!!!!!!!!

RaceHorse

Sorry I am of no help with your fuel system, but congratulations on crossing the 200, 000 mile mark. I thought you would have based on previous posts. I have done it 3 times, but not quite as enjoyable, 2 Hondas and 1 Acura. You are certainly getting alot of enjoyment out of your car, and more seat time than any others, enjoy.

Quinlovescars

Not completely on topic but how does the car drive and run at 200,000 miles? Have you had any big issues? Looking at picking one up within the next week and plan to daily drive it!