Audi A3/S3 2.0 TFSI Quattro Hot Start Issue
 

Hi everyone.
I have a 2015 Audi A3 2.0 TFSI Quattro 220hp.(Bought it 2 months ago). I got P0087 fuel system/rail pressure too low error for a few mins when I was idling last month and then it disappeared itself. A few weeks later I got some weak battery symptoms like hard start etc and I changed my battery in a mechanic. After this some hot start issue showed up in my car. There is no any issue when I cold start. However when I drive the car for a few hours and if I park it for 5 mins to 1 hour, Engine is working and running just a few meters and then it's stalling. It's stalling only when I start to car in that moment. And I need to wait a few hours to cool it off and then I can drive it normal. It never stalled during drive. And It never stalled when I cold start it. This happened 4 times in 3 weeks. I got P0087 each time however engine light disappear after a while. I went 2 different mechanics and they couldn't pinpoint the issue. First mechanic tested the car whole day and they couldn't see any performance issue. Because this problem happens intermittently. Second mechanic said everything is possible, we said maybe Audi can pinpoint the real problem. He said HPFP, LPFP, Fuel pump module, FP Sensor can be.

He said my HPFP replaced with the original one before. I'm thinking that maybe weak battery + low fuel level worn out the LPFP or Fuel pump module or maybe sensor. There is no any issue when I at high RPM like 4000-5000rpm.
Anyone have an idea ?

Have a great weekend!
Arda

Re: Audi A3/S3 2.0 TFSI Quattro Hot Start Issue
 

My mechanic replaced the fuel pump driver module and unfortunately nothing changed. They replaced the fuel pump in the tank first a few day it was good however it started to stall at low speeds and idling. I can only drive 10 mins now and then it stalls. Any idea ?

Re: Audi A3/S3 2.0 TFSI Quattro Hot Start Issue
 

Hi, have you find out the issue because i have exactly the same than you. I replace hpfp without success, check evap canister and purge valve. All is good but cannot find out. Thanks

Re: Audi A3/S3 2.0 TFSI Quattro Hot Start Issue
 

Hi Felix, I got back my car from Audi Shop last week. I had replaced my fuel pump in my mechanic. Audi found out new fuel pump wasn’t connected to suction jet pump. suction jet pump delivers fuel from the left half of the tank via another fuel pipe to the right half of the tank adjacent to the primary pump. Audi connected it and replaced the seal. Fuel pressure was 0.8 around it’s 2.3bar right now. Looks like everything is fine. I need to drive the car more than 5-6 hours to understand that my car completely fixed.
Summary I replaced the fuel pump driver module and nothing changed. I replaced the fuel pump probably that one was the problem but my mechanic forgot to connect suction jet pump to the fuel pump. I recommend Audi Shop. The service was amazing. No one can care my car like that. They did 4-5 times road test 2 of them is overnight road test. Car stalled on technician, they towed it back to the shop. They check everything else too. They literally pinpoint the issue. Please update me with your next steps. I'm not 100% sure my problem is fixed or not. But I haven't see any symptoms in my car yet.

Re: Audi A3/S3 2.0 TFSI Quattro Hot Start Issue
 

All liquids, oils and other things were fine. They checked the engine side first, they couldn't see anything in front side but the fuel rail pressure was dropping from 0.8 to 0.5 around and the engine was stalling. The technician said it should be above 2 bar. They checked the all fuel lines and fuel tank and my new fuel pump as well. Only thing that they found is connection issue between fuel pump and suction jet pump. So your issue might be fuel pump in the tank. Because it's the last thing that I replaced.

Re: Audi A3/S3 2.0 TFSI Quattro Hot Start Issue
 

Arda[/QUOTE]
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Re: Audi A3/S3 2.0 TFSI Quattro Hot Start Issue
 

Hey Arda,

I'm having the same problem with my S3. I've fixed the HPFP but have yet to dig into the fuel tank. Did you find out what the issue ultimately was?