St3phen

In March, I got a CEL, took the car to the dealer, and they said that the code was for intermittent misfires on cylinders 4, 5, and 6. They replaced injector #4 and cleared the code.

About a week later, I got another CEL. I don't drive much so didn't act immediately on it. I VAG-ed it myself and got the same code. So, I brought it to the dealer yesterday. After a bunch of diagnosis, they determined that my fuel system is contaminated.

They found a "fine silt" in my gas tank, which has made it's way through my entire fuel system. The fuel filter is about 50% full of this silt. I have had them keep a sample of this silt-infused fuel.

The remedy is removal + cleaning ($900) OR replacement ($1800) of the fuel tank and a chemical flushing ($130) of the fuel system plus replacement of the fuel filter ($100).

So, fellow allroaders... any ideas what this silt could be or how it is entering my vehicle? This never happened the entire time that the car lived in California. Since moving to Missouri, I've only gotten gas at Costco in "south county" St. Louis. Could Costco's fuel system be contaminated with this stuff?

A friend of mine says I should approach Costco to pay for the repairs. I'm not sure I am comfortable with that. I mean, I have used their fuel exclusively since the beginning of February. But how do I know it was the gas station? I'm not sure what else it could be... but somehow that still seems like a stretch.

greenmeanie

Fuel is dirty is the first thing. It gets worse if you pump when the stations tank is either almost empty or the delivery truck has just been and stirred everything up. In some places there are local laws controlling the maintenence of the petrol station tanks etc. It used to be more of a problem when the tanks were all steel and would corrode.

I am going through this myself, but only on my Landy 101 which fortunately has a comparitively simple carb fed system. After a complete engine rebuild I bought a tank of fuel. I could go 1 mile from start up and the engine would die from fuel starvation. On inspection I found about 1/2 inch of silt in the bottom of the tank that wasn't there the previous week. I have drained and cleaned the tank, changed the fuel pump, cleaned all five filters, blown the lines clean and pulled, stripped and cleaned out the carbs six times now. Fortunately this is comparitivelty simple to do on the truck. Starngely, I was commenting to my wife that I am glad that it was not her car that had been filled with this crap.

If you don't go full on with the clean out you will be chasing this problem for months as silt can hide in nooks and crannies in your fuel system. Every time you think your done it will come back.

I would contact your local BBB and see if there is any way you can get recompense for the repair.

Cheers
Gregor

paulroad

Is the CEL FLASHING or just staying on solid?

If there really is crap in the tank and it is fine enough to get past the filter? This is weird. Replace the filter for starters.

Audi Maint should do this at N/C

If its provable then get to COSTCO..there is no other place it can come from, unless your tank is rotting..doubtful.

quackroad

If they get a sufficnet number of complaints, they'll likely take the costs and pass them on to their fuel supplier, if they can. Or own up to it to avoid a class action. Or not, either way it can't hurt to let them know.

Ex-PzKW Cdr

Costco doesn't have a refinery and so therefore buys tankwagon. This means they bid on whatever junk is left over after the local refinery has met it contract for it's local distributers. Sometime this can be 93 Sunoco Ultra, or 86 **** from the local farm impliment refiner. It's then blended together and doctored with additives to meet the minimum, detergency and octane for the purchaser.I tell people all the time, buy only from companies that have refineries and are local. Now if you're a 2003 or earlier , you may have a bad ignition output module, (the little black modules on the air cleaner.) Before spending crazy money at the dealer, change the fuel filter, buy 2 bottles of TECHRON fuel system cleaner, nothing else, don't cheap out here, find an Amaco or BP station, when you're just about empty, and dump both bottles in, fill to the top with premium. Drive it until it's almost empty again, change fuel filter again. See how it runs.If this doesn't help and their diagnosis is still injectors, I doubt their cleaning will do anything. I have NEVER seen a fuel injector cleaning do squat, other than seperate you from your money. If Techron won't help you'll probably need to pull the injectors and clean them MANUALLY. They have very fine mesh screens to keep debris out of the pintle. Replacement may be necessary in cases of accretion type contamination. (Sugar,glue, plastics,etc.)

St3phen

the fueling truck anywhere near a gas station, I don't fuel up there at that time.

I've authorized the complete cleaning and flush, but one thing that you said triggered my memory of something the service manager said as well. He said that if I didn't get a brand-new tank that there was a possibility that the tank could harbor some of this silt in nooks and crannies within it.

Would you recommend a new tank at 2 times the price of the off-site tank cleanout? Or were you referring to the flush of the rest of the system?

St3phen

fool around driving a car with a flashing CEL. Unfortunately, my car is a year out of warranty and my aftermarket warranty, as you might imagine, does not see this as a defect in the car.

I'm having them replace the filter. I'm not even sure how I'd go about talking to an organization as large as Costco regarding this. However, I am 99% certain that I've only fueled-up there (except for about 5 gallons one time at a convenience store near my home) since moving to MO...

Also, they checked the three coilpacks on those three cylinders. All supposedly passed the checks.

St3phen

I am done purchasing St. Louis Costco gas. (Right?) Oh well, that was fun while it lasted. Odd that I never had this issue in CA. I was just happy to have 93 Octane again (after frowning every time I purchased 91 in California).

greenmeanie

When they flush the system do they drop the tank or do it in situ? I would expect them to drop the tank in which case is should be OK just to flush. (Sorry , just re-read your post and realise they will drop the tank.)

Between the flush removing most of the gunk and the filter I would not be too concerned. After all the fuel we buy every day has some crud in it which is why the filter is there in the first place.

Someone who has been there can probably answer whether the fuel pump has an intake filter sock on it. If not the silt will have shortened the life of the pump considerably.


Cheers
Gregor

St3phen

will actually be dropped, removed, and taken offsite to a specialist to clean it out. I imagine the remainder of the fuel system flush will be done while the tank is off.

I hadn't even thought of the pump. Ugh.. this just gets worse.