Ok, I know that there are a ton of really smart people on this forum by the looks of it. So, I'm asking for your help!

I have an 2002 Audi S4 Avant with 33K on it... yes it is brand new. However, a light on my dash just came on so I took it to the authorized Audi repair center in my area. After a week of system diagnostic test the two top codes that keep coming up are:

P1130 = Long term fuel trim, too rich
P1139 - Additive Fuel, too rich. Rear oxy sensor, poss air mass, evap purge valve
P0442= Evaporative emission system, small leak

They have checked all vacumm hoses which are not leaking, top and under car at turbo area which is all good, no leaks and the turbos are great. The Fuel pressure is good and they ran the car with the scan tool on and the oxy sensors are all working properly. At this point they aren't sure what to do. They think that it may be the injectors, air mass, or evap purge valve but this is like 6 more hours of work. The car is just running rich, which in the long term might ruin the catelitic converter.....

Has anyone ever had this happen to them or heard of what it might be? It might be something so simple considering they have checked just about everything.

Any suggestions are greatly appreciated!

Thanks,

Jen

 

Sounds like you have 2 distinct issues... In reality, the long-term fuel trim and the evap system don't have much to do with each other.

Regarding the LTFT... I am betting that your 'rich' condition is linked to this. The LTFT may be over-calculated. The system thinks there is more AIR than there actually is. So, this could either be a vacuum leak or an air intake restiction. Another cause could be that MAS is reading incorrectly. The only way to determine fuel trim is by the use of the MAS readings over a period of time.

Regarding the EVAP system... A faulty purge valve/solenoid could be the issue. I am not sure how much emmisions are recirculated in real-time. If the leak is not to Atmosphen (the evaps go back to the intake manifold continously) that may explain some of the 'rich condidtion' and would attribute the the evap CEL and may throw off the LTFT too.

These types of problems are completely annoying and take careful troubleshooting to correct. Personally, I hate taking cars to the dealership and do everything I can to fix the problem myself. Its a matter of weather or not you have the time and patience to dig the problem out.

I would be interested in what the solution is... But, my advice would be to work the problems seperately as if they are not linked. Try to solve the LTFT issue first. If you can't do this, then start looking towards the issues as being related.

 

i'd say codes are related...P0442= Evaporative emission system, small leak, Bank 2 is your #1 problem then as a result your getting P0442= Evaporative emission system, small leak, Bank 2. They were on the right path with the 02 sensors. If they suspect these other problem why couldn't they pull parts from the shelf to test. Good luck!

 

What?