Hello my 1999 audi 16 2.8 avant quattro is giving me quite the issues the abs and brake lights stay on constanty, the car now has trouble starting to where it cranks then everything including electrical goes dead, then when on and only sometimes when switched into reverse it'll die. any thoughts?

-Don't worry. Even the abs is not function properly but the basic brake still work like normal car.



Good luck



Mai

1999 Audi A4 Quattro Avant

The Low pressure A/C refrigerant port

The High pressure A/C refrigerant port

That indicates that the ABS controller is having issues. The ABS controller is the metal box along the driver's side of the engine, just in front of the coolant overflow tank. The controller is the black box on top of it with the harness attached. You can buy a new one (expensive) or send yours to www.modulemaster.com for a warrantied rebuild. They have a great reputation on the Audi forums I frequent, and you can drive the car while it's gone (you just won't have functioning ABS while it's gone).

If it's like my 2000 Passat, remove drivers front tire, remove the plastic wheel well ( about 10 screws) this big peice comes off giving you access to the windsheild washer fluid holder.

around $1000 Sorry :(

This is a manual transmission? If so the clutch probably needs to be replaced. When you say "VIOLENTLY" what is going on, what is the road speed, what are the RPMs at? The more specific information the better. And this problem ONLY occurs between gear changes, right? The other times, everything is normal?

you prob need a new abs sensor

Here is a manual, but you have to purchase it:

http://shopping.msn.com/prices/audi-a4-service-manual-1-8l-turbo-2-8l-including-avant-and-quattro/itemid2373553/?itemtext=itemname:audi-a4-service-manual-1-8l-turbo-2-8l-including-avant-and-quattro

This is common in the audi cars. It may be that your ABS module is failing or the the connector to the ABS pump located in the engine compartment on the drivers side, with black metal lines going into it. Their is a large black connector that sometimes needs to be unplugged and cleaned and plugged back in

Speed sensor located in top of rear diff is probably bad, It sends a signal to abs module for abs, it also is used by pcm and cluster for vehicle speed.Sometimes rear diff mechanical problem can damage the sensor. Trans sensors have nothing to do with speedo or abs light.