Amber engine warning light

[johnp68]

I have a warning light on my B6 S4 dash. Engine appears to be running ok. Vag-com shows the following error codes:

VAG-COM Version: Release 409.1-US

Control Module Part Number: 8E0 910 560
Component and/or Version: 4.2L V8/5V 0040
Software Coding: 0011711
Work Shop Code: WSC 12595
2 Faults Found:
17535 - Fuel Trim: Bank 1 (Mult): System too Rich
P1127 - 002 - Lower Limit Exceeded
17537 - Fuel Trim: Bank 2 (Mult): System too Rich
P1129 - 002 - Lower Limit Exceeded

Before I get round to booking it in at a garage, can anyone please tell me what these error codes mean?Thanks

 

[paul20v]

Hi

MAF troubles lead to under-estimating the air in the system which lead to "lean" codes, not "rich" codes.

Also Check your airbox for debris, and check your intake hoses, hose clamps, & vac-line check valves.

 

[howdy quattro]

could also be a lambda sensor fault or trouble with your cat.

 

[blackpool1974]

http://www.ross-tech.com/vag-com/cars/fuel-trim.html

Basically your engine is bunging in the fuel when you are at driving (not at idle) but whatever the amount of air that is going into the engine, the air meter sensor either isn't measuring it correctly or something is stopping the air getting through, so there isn't enough air to go with the fuel to combust, so it is running rich, the ECU compensates by reducing the injector timing to bring it in line

On your vagcom check measuring block 2 on the engine and check how many g's of air your air meter is sensing, you might need to put your foot down a bit as you dont have the problem at idle

On your vagcom check measuring block 32 on the engine second window will tell you how bad it is the higher the - figure the bigger compensation the ECU is making to equalise the air and fuel

 

[johnp68]

Thanks guys. sounds a bit complicated. think i'll take it to the garage to get it checked over. the car's been revo'd (couple of years ago) so not sure if this would make a difference.

 

[AudiJohn]

There funny these amber warning lights - appeared on mine after i'd changed the cam-belt with the car running better than it was before, i was told to take the negative lead off the battery and leave off for 5-10 mins so i did but it was still on annoying me whilst driving.

Then last week i replaced the battery with a new Bosch s3 and while i was there i cleared out the drain channels of leaves etc with the battery not in place. I Put the new battery in after about 20mins and the light has gone, Ididn't have to put the radio code in or rest the clock which i thought was strange (is there another backup somewhere?) The light has not come back on (touch wood) so i can say iv'e probably saved about £70-80 by not letting the dealers reset it. Not the same issue as you have but if you say it's running the same it's worth a go !!!

 

[johnp68]

http://www.ross-tech.com/vag-com/cars/fuel-trim.html

Basically your engine is bunging in the fuel when you are at driving (not at idle) but whatever the amount of air that is going into the engine, the air meter sensor either isn't measuring it correctly or something is stopping the air getting through, so there isn't enough air to go with the fuel to combust, so it is running rich, the ECU compensates by reducing the injector timing to bring it in line

On your vagcom check measuring block 2 on the engine and check how many g's of air your air meter is sensing, you might need to put your foot down a bit as you dont have the problem at idle

On your vagcom check measuring block 32 on the engine second window will tell you how bad it is the higher the - figure the bigger compensation the ECU is making to equalise the air and fuel

Back to Plan A! Garage only had time to look at the error codes and tell me what I already knew (running rich) and said I would have to book it in to allow them time to do some logging. I might as well have a go at doing that myself before I book it in.

Do I need to record the logs with the engine under load, or can it just be parked up and in neutral? If under load, do I need to do the "full" runs that I remember reading about when I was thinking about tinkering with settings on revo and measuring the impact (ie 100% load, 3rd gear from 1500 rpm to 7000 rpm say?). Thanks

 

[blackpool1974]

You need to see what you air sensor says its reading first, measuring block 2. if its duff and saying to the ECU that it is sensing 10g's of air then it will fuel it accordingly when it might only be actually receiving 3g's

IE running rich

I cant see the purpose of any other logging

 

[johnp68]

Now back from hols, so have done some logging on vag-com!
Block 2 is reading about 5 g's at idle, rising to around 100 g's at 7000 rpm (car in neutral)
Block 32 is reading 0, -18.8, -0.8, -18.0
Any ideas? Cheers