Fuel Injectors G210 / A6 1998 AFB

Today, my car broke down. The error code is G 210, which indicates a fuel shortage and an implausible signal. This means either I ran the fuel tank empty or the sensor is defective. Now the question is, how can I quickly determine the cause: is it the fuel pump or the sensor?

Open the fuel tank sender access cover and look inside to see if there's fuel in the reservoir. If the tank is full, then the sender is likely the problem.

Okay, the fuel tank is almost empty, but the fuel light hasn't come on yet. The onboard computer says there's still 100 km of range left. I guess I'll have to add some diesel before I try to start it again. Is it possible to replace the sensor individually?

Okay, so we've now added 15 liters of diesel, bled the system, and the car is running without any problems. The fuel pump in the tank is also working perfectly. There are no error messages anymore. Now the question is, what caused this? Because the diesel filter and fuel lines were completely dry. However, the fuel gauge was in the red zone at the beginning, and the yellow low fuel warning light hadn't come on yet. About a week ago, I could drive it with the yellow light on until almost the end of the red zone. What should I do now? Will the same thing happen again? Maybe the float got stuck, and the tank was actually empty? Give me some advice on what to do now. It's running fine now, but what if the tank empties again? Hmm, what a stupid mistake.

When the time comes again: Open the fuel tank sender access cover and take a look inside to see if there's any fuel in the reservoir.

Okay, I've now noticed that the check engine light (indicating the error) comes on when I'm driving really fast. The other day, I was driving on the highway at 200 km/h or more, and then it started blinking, even though the tank was half full. I then cautiously refueled and drove normally, occasionally using the kickdown, but nothing happened. It really only happens when I'm driving aggressively. And I remembered that when the error first appeared, I was also driving very fast beforehand, meaning I had been using full throttle for a long time. It can't be the fuel gauge because when the error first appeared, the tank was at the beginning of the red zone. And as I said, I've been driving normally for days, and everything works fine. However, I'm now hesitant to drive fast or use full throttle for extended periods.

Telepathic healing is difficult. You are stubbornly refusing to even take a look at the likely faulty component. Perhaps the pump isn't able to deliver enough fluid when the demand is high. Maybe air is getting into the return line and creating so much foam that the sensor is reporting a low fluid level. Maybe...

"So, we took everything apart and cleaned it today. We removed the entire pump and cleaned the filter, hoses, and everything else in the tank. We tested the pump, and it's working; I don't know how much pressure it's supposed to generate, but diesel was coming out of the hose. One thing I found strange is that the hose coming from the pump has a T-piece about 10 cm from the pump. One branch goes to the charcoal canister, and the other goes towards the rear of the tank. When I hold the hose that goes to the canister, it only drips slowly because the pressure is being diverted in the other direction (the T-piece). If I block the hose going towards the rear, then a good amount of diesel comes out of the hose leading to the canister. Anyway, I drove about 20 km, and the warning light started blinking again in the instrument cluster, even though I was only driving at 100 km/h, so it probably isn't related to the full throttle situation. I'm really not sure what to do next. At first, the problem only occurred when I accelerated hard, but now it's blinking even at 100 km/h. What's strange is that, if there really wasn't any diesel in the charcoal canister, which shouldn't be the case, because when I had everything open in the back, I saw that the canister only relies on the pump when it's running low. My tank was half full, so the canister was full anyway, and the light/warning wasn't constantly on; sometimes it would blink, then nothing for 5 km, then again for 20 seconds, then nothing again, etc. It can't be a diesel shortage; I think the fuel level sensor is probably faulty. It's just a small float switch. Even if the pump wasn't running, it would still get diesel until the tank is about half empty because the charcoal canister would be full until then."Otherwise, I'm completely at the end of my rope with this Latin!

Do you have a Fronti or a Quattro?

Fronti. Why?

Because the Quattro has two fuel tank chambers, the pump has to be operated via a suction pump. This could have been a potential source of error and an explanation for the second hose.

Hmm, it's not a quattro. I filled it with 20 euros of gas today, and now nothing is blinking, but it wasn't empty because I had the cap open the day before and there was still a lot in it. The question is why the low fuel sensor triggers so early if the yellow fuel light doesn't even come on. Sometimes it works fine, and I can drive it until it's almost empty, so the fuel gauge seems to be working. Why does the sensor always trigger immediately even though there's still enough fuel in the tank?

The fuel level sensor is located in the fuel tank, while the float sensor is located in the float bowl. So, to reiterate, what does the float bowl look like, not the fuel tank, when the sensor gives a false reading?
I looked at this part in the repair manual. The hose that goes to the back connects to a T-piece, and from there it goes into the surge tank housing from the outside, where a jet pump is located. This pump then sucks the fuel from the tank and "pulls" it into the surge tank. I'm not sure what the other branch does, as it seems to go directly back into the surge tank. Perhaps it goes to the other half of the tank in the Quattro models, but if that were the case, it shouldn't just drip, but rather flow equally from both ends.

Wouldn't it be possible to run the pump with the ignition on, pump the fuel into a plastic container, and, as Christians correctly pointed out, check the level in the tank when the light comes on?
You'll also be able to see the flow rate in liters per minute, whether there are any bubbles, and when the fluid stops reaching the front of the engine.
Refueling without checking is pointless.

It doesn't work quite like that. The pump only pumps into the collection tank.

Right, I thought there might be another pump in the front.
Then the EP only draws power from the battery, and the battery must always be full.
Okay, put the spare canister and tools in the car, and drive until the fuel light comes on, then check immediately to see if the tank is empty!