Fuel Pump replacement issues. Need advice and knowledge with workings of car and how to handle

My gorgeous 2005 Audi Ultrasport A4 1.8t Quattro 6spd is not as it used to be from a somewhat recent botched dealership repair.

I got this repair done in June 2013 at the Jim Ellis Audi in Marietta in Atlanta, GA, after I thought I bought bad gas at BP. After filling up, 3 miles down the highway the car sputtered and I couldn’t accelerate nor start the car and had it towed to the local Audi Jim Ellis dealership. I paid $1100 to have the fuel pump and fuel filter replaced. After the initial fix the car would make very loud whining sound when on a half to quarter tank of gas and lower and the digital dash gauge of miles to empty would fluctuate up and down which I’d never seen before. I ended up taking the car back in 5 times before it seemed like they finally got the whining issue fixed, was told that they had to replace the fuel pump and fuel filter a second time as debris from the fuel pump had clogged the new filter. I’m currently between jobs and after speaking to others about this I decided to start digging back into this repair since I have more time on my hands and after my $2000 water pump/timing belt fix 2 weeks ago and know keeping the car for another year.

3 Main issues that resulted from the fuel pump repair that still haven’t been fixed yet and I’ve relayed this every time I’ve brought the car back in. These issues never where present before this car had this repair. This car used to drive like a dream with a N75J blowoff valve and APR R1 diverter valve. I know these cars pretty well and do all my own maintenance that doesn’t require a special machine. I can’t help that the Service Rep only puts down the obvious issue of the fuel system squealing in this “customer states” section of his repair tickets when I brought it back in the 4 initial times. When I mentioned the gauges not showing correctly anymore when I’d bring the car back in for this, I was told too bad. At the time I had pictures of the dash while driving that I brought in showing the gauges not working as they once did, for example I’d be driving and the dash would say I had 50 miles to empty then after driving 1 mile or less it would go to 55 or 60 and then goto 45 on flat ground and when sitting in traffic. What am I to do? It eats me up to think that I’m getting screwed.

  1. No fuel pressure in the gas tank when opening fuel cap to buy gas. Used to make a loud whooshing sound when opening the gas cap every time I’d buy gas before this repair. The YouTube video shows my car with a low fuel tank after I just filled up and 3 hours later when empty to test issue, car has no fuel pressure in gas tank like it used to before this repair was done.
  1. Digital and stick gauges in the dash no longer match each other nor the car’s actual fuel reading and the readings of miles to empty, instant mpg, and average mpg are not the same as before. Lots of ways to show examples of this. The miles to empty reading goes up and down and doesn’t hold a true reading anymore. Before the repair the miles to empty dash reading never increased or bounced around up and down, now it can’t make up it’s mind on how any miles until empty is left. In the YouTube video I took on Friday, the car’s low gas indicator on the dash had just come on but the gas stick meter showed the car’s gas was completely empty when it should’ve been at 1/8 of a tank like it used to. No way to really know consumption when looking at dash or when fuel is actually low or empty.

  2. Getting 10mpg less than before repair was performed. Car now gets 17-19mpg in the city and 24mpg on the highway and the day before this repair was done initially the car used to get a great 34mpg highway and 24mpg in the city. Knowing this was done by math and not looking at the dash’s information as the dash’s info is all over the place but the data used to be spec on the dash before this repair. I know all this because I pay attention to this stuff meticulously since I’ve bought the car and have always pride myself on having a car that is the best mix of performance and fuel economy. The dash’s average mpg also agrees that the car gets 10mpg less than it did before this repair which shows 24mpg when driving on the highway and used to be 34.4mpg on the highway. I reset the meter to show this so the reading is only during this type of driving, not the average from different speeds. This is why I bought a 1.8t 6spd Ultrasport as this car was the best 1.8t Audi had ever made.

All systems are 100% on the car so there’s nothing else that could cause this. Tires are new as of last week with 40psi, new fully synthetic oil change 2 days before Friday’s video of getting gas after a full tank of use in 3 hours of driving an entire gas tank to empty, new timing belt and water pump 2 weeks ago, and new brakes on the car 4 months ago. Only premium gas has only been put in this car. I’ve spent $4500+ this last year in keeping this car spec. Makes me sick the car is only worth $5-6k if I trade it in.

I spoke to the service rep today and he will not listen to any of the car issues. I didn’t even get a response after calling and leaving a voicemail on Friday and then following up with an email this afternoon similar to this write up to him and his service manager. He says the car is fine and the missing pressure sound from opening the gas cap is normal even though before this repair it made a loud whooshing sound every time I’d open the cap to buy gas for years when owning this car. He said that there’s a sensor in the gas tank that alleviates pressure when the car is off and the car is to not have pressure shown/released when the cap is removed. I asked if there are newer parts that changed things as it never used to be this way and he said no. I think that is lying that it’s normal for the car to not make an air pressure sound when opening the gas cap. I know the cap itself is fine as the car passed an emissions test in August. I think the car thinks its working fine but there’s issues that sensors aren’t catching. Would a air leak in the fuel tank cause a drop in fuel economy?

Can some please reply and tell me that the car’s fuel tank should be under pressure? Our emissions testing here requires a gas cap to be air tight so maybe now that my fuel tank is no longer air tight, the car was released back to me in a way that’s against the law? I think that all these issues listed are because the pressure isn’t held in the car at least from tank-pump end. The car seems to drive ok. I also think that opening and going into the fuel pump 5 times, that the seals could be worn and leaking.

He offered a $150 diagnostic fee to check into things but wouldn’t take the car back again and accept that this is from the fuel pump repair which is obvious to me. I don’t want to pay for issues that I know are adverse affects of repairs done there. They told me when I got this done that there’s a 1 year warranty for work and parts done by them.

Please help!

No offense, man, but your story is way too long

My late father, who was an english teacher, used to say “Simplify”

Its all heresay but a few years back my BIL told me about similar problems from someone using BP. I don’t buy gas there anymore. I think you got a bad tank of gas if it happened right away. The fluctuating guage would be from an unstable float in the tank or a bad sending unit in the tank. They should have replaced all that with the pump. Outside of dumping the tank and cleaning it, new sending unit or new wire harness or cleaned contacts, new filter, I think fuel system needs to be gone over and maybe cleaned. Don’t know what that would be though and you’d need a repair manual. Gotta be more than one dealer or import shop in Atlanta though.

The fuel tank should not have any positive or negative pressure when you open the gas cap. The system is designed to relieve pressure without venting to the outside world. Clearly there was something wrong before the repair. I’d suspect a crimped lined from the tank right from the factory that they fixed by accident when they dropped the tank and reinstalled it.

I would have a fuel pressure and volume test done to ensure the engine is not being starved. The evidence you laid out points in that direction. If pump checks out, I would inspect each injector spray pattern on bench to make sure they’re not plugged up with debris.

Hounding them is having the opposite effect as often happens when dealing with people. Time to go somewhere else but keep it simple and non-confrontational.

One thing I always did was to leave a concise description of the symptoms on the seat for the actual mechanic. The service writer isn’t going to capture that detail. Had mechanics come up and thank me for doing that…of course I was thankful they got more info to do repair right first time.

+1 to Twin Turbo’s comment.
There should never have been an obvious pressure release when the gas cap was removed, so if nothing else, at least that problem has been rectified–even if the OP did not realize that it was a problem with the car right from the start.

As to the rest of the post…I’m sorry, but I just can’t wade through that much detail.

Maybe venting has improved the OP’s disposition some.

And as sometimes occurs the post “talks so much yet says so little.”

Is fuel mileage decrease that is noted actual calculated mileage based on odometer mileage and gallons pumped or is that figure from a dashboard indicator?

It is not unusual for a car owner to become aware of a fuel pump’s hum after paying to have it replaced and not realize that the original pump was just as noisy.

Often a service writer must filter through an excititedly verbose complaint in an effort to “cut to the chase.” It can be difficult to seperate the mechanical issues from the drama.

In Ga they check that the fuel cap maintains pressure. As long as your cap is good, that portion of the test will pass. The other portion reads the PCM through the OBD2 connector and as long as you don’t have a failure, you will pass.

Thank you for your replies. I was a little heated when writing that. lol

Good to know that air shouldn’t be sucking into the fuel tank with the whooshing sound like it used to after burning a substantial amount of gas. Maybe only cheaper cars do that, like my father’s brand new Nissan Altima? I’ve always known the more pressure built the better fuel economy, which is why they say you get the best mpg when filling up a full tank of gas and not incremental. After learning as much as I could online and watching fuel pump repair videos on YouTube, they said that every time the fuel pump area is opened that the large rubber gasket needs to be replaced, and I bet it was never replaced or only was done on my 1st visit. I don’t remember reading that part on my receipt. I figured that was my next angle.

The initial whining sound from their first attempt was coming from the fuel filter having debris in it. It was so loud that people on the street would look at me crazy when waiting at a red light.

I’ll look into a fuel pressure, volume test, and injector spray pattern bench. Also start pricing repairs of the float and sending unit in the tank, maybe I can do myself. Would a fuel flush from the pump to the filter and filter to the engine would be good too? The Audi service rep said that there are sensors in the engine that monitor fuel pressure so they’d know if the engine was receiving too much gas or starving.

Just sucks that I have to pay to get these things checked out as a result of a repair that makes my car drive and perform less than it was. I just wish Audi would do all this to ensure their repair brought the car back up to factory specs and if something was found then we’d work out a cost. I am grateful that the car is running ok.

Someone needs to invent a DIY service station where a knowledgable car tech works with you on your own vehicle and you can ensure every part is refreshed and replaced. I love working on my car!

" I have always known that the more pressure built the better the fuel economy" . You seem to know a lot of things that are not true which is probably why the people at your dealership have stopped paying a lot of attention to you.
I don’t understand why your anger is reserved for your dealer and why BP isn’t paying for your repair instead of you.

Some cars do use a pressurized evap system. Chrysler for example. Not certain about Audi.

One caution: Working on fuel systems is hazardous duty. Make sure all the safety precautions are followed. This is a job in fact you might want to delegate to an inde shop that specializes in Audi or German cars. Cleaning out the fuel system after a bad tank of gas isn’t something I’d use a dealership for unless it was under warranty.


Don’t be so quick to judge

Many fuel pump assemblies come with a new seal inside the box . . .

Just because it’s not listed on the invoice doesn’t mean it wasn’t replaced

If air was sucking into the tank, that is vacuum, not pressure. I have owned about 15 Chrysler products and not one of them made a noise when I opened the cap. I drove a few GM products that did at work.

It’s near impossible for me to even venture a guess about cures for the problems presented. The multiple replacements of the fuel pump and excessive whining comes across as very strange.
I don’t think going into the tank 5 times is the cause of a problem (maybe) but one has to wonder WTH they’re thinking by repeating the same verse over and over.

The pump assembly should have the fuel gauge float as part of the unit and I wonder if the float arm was bent during the installation? That could affect the fuel gauge reading as could a problem with the wiring at the tank connector, poor ground wire at the tank, etc.
I’m sure the dashboard readout works off of a module that receives input from the float, or fuel sender as it’s called.

Regarding the fuel mileage drop, you state the car went through a timing belt job recently. A loss of fuel mileage could be explained by the belt timing being off a tooth or two. Not saying erroneous belt timing is the cause; only a possibility.