Hey all...

I got myself a great deal on a 2001 a4 1.8tq 5sp back in december. I absolutly love the car. The look inside and out is just awesome. I have been into VW all my life and owned many. The next logical step in my case was an Audi. I immediately purchased spings/shocks etc.. and a chip. I got an APR. I am not sure what I think about it, but if you read on and I will tell you what I do think and would appreciate some advice. Anyhow shortly after I bought the Audi I noticed that there was this strange noise that was happening only when cruzing (just enough throttle to keep the same speed). I didn't do much about it for a while until my guage cluster started to act funny and the spedo stopped working. Which in turn made the odo stop working. I took it into Stevens Creek Audi, I tought it was convienent as I live only a couple of blocks away. Wow was I wrong! They replaced my guage cluster, and rebuilt my tranny 2 times. Yes twice. This all took a month as they were waiting on some crazy special tool to put the tranny back together. Really what's up with all of vw/audi's special tools. I must have half a dozen and come in handy only once and a while. So I was really pissed to get my car back after such a long wait. They f'd me on some charges for the rental car, but whatever I'm not welcome there anymore. So after all that, the tranny doesn't make this noise anymore but definately grinds into second when the car is cool. I am not talking about revving to 4k either it will grind if you shift at 2500 or anywhere for that matter. And the gas guage has a range of full to half full. So it doesn't work right either. They (audi service) may have messed up the sender in the trunk as the car smelled of gasoline as well after I picked it up. I checked the fuel pump, and guess what the big "o-ring" on the inside of the opening was pretty much halfway shoved into the gas tank while the other half was sealing. So as you can imagine it leaked. I fixed that and the gas smell went away. I now have developed a new problem. I have been driving around with the chip OFF about 90% of the time and only turn it on for some spirited driving. I was planning on getting a new diverter valve and didn't want to sress the stock one too much. The check engine light came on and the car is in limp mode so to speak. I checked the code and it is : System too lean bank 1. I searched the forums and cleaned my MAF. Didn't change anything. Some people have said to change the o2 sensor before the cat to fix this. I bought an o2 sensor for a vw 2.0 (was told was the same sensor with a different plug at the end). I would try this as a fix but I cannot figure out what wires go where. The new sensor has a white, black, and two grey wires whereas the sensor in the car has colored wires (not grey or black). I need to take the car in for the 50k service and I would rather it be without the CEL on. I'm concerned it is the APR chip at fault. I have read others with very similar issues. I don't want the dealership to say it's the computer and see I have a chip and my 100k warranty is out the window.

So my questions are:

1. Could the APR chip be causing the CEL?
2. If so what's the best solution, I can try the new o2 sensor if I had the wiring diagram, or I would even change chips to a giac or *recommendation-here*. (can this be done? unsolder the apr and put something else on?)
3. Can I get a spare ecu? Where? How do I tell which one I have?
4. What is the best audi service dept. in the bay area.. preferably in the south bay.

Thanks for your attention, I know it was kinda long winded. I just need my baby back to normal so I can have some fun again!

 

it could have been the o-ring causing a drop in fuel pressure that tripped your CEL, it could also be your pre-cat o2 sensors, or a number of other problems...replacing your o2 sensors is a good start, they're fairly cheap for that MY and it can't hurt to replace them...if you haven't replaced your dv i would do that right away, the stock valve will fail soon if it hasn't already and you'll lose a considerable amount of power, you can get the TT dv for 35 bucks at the dealership...i use diablo audi up in concord and they're awesome. i don't use the dealership for much, but when i need them, they're always helpful, especially their service department. i've been to steven's creek audi and i don't like them at all.

 

So does anyone have the wiring I need to install the pre-cat o2 sensor? As I mentioned before I purchased an o2 sensor for a vw 2.0. It is supposed to be the same except for the plug at the end. And apparently the coloring of the wires. Does anyone have this info?

 

unless you have an ATW engine code, DO NOT use that VW 02 sensor you bought. They do not work on most audi engines.

I doubt the chip is the problem - APR is a solid company. However it is slightly possible that its a bad solder job.

The fact that the o-ring was misaligned is probably your CEL. Evap(fuel) systems leaks will throw CELs. The lean code could have resulted like bentframe said, a drop in fuel pressure.