forum.audiv8.com Foren English Audi V8 Forum V8 help

Hello!!!

I hope somebody can help me fix the problems I have in my V8.
To start, I will describe all the symptoms and details; they might be related or not.

1) The car has 230,000 miles and pretty much all the records, last timing belt job was 20 K miles ago. Now, it needs some work on the front end (bushings and other parts) which I am planning to do as soon as I get them.

2) About three months ago (end of summer here in Buenos Aires), the “check engine” light came on and the most noticeable things were: a) the way it affected the transmission (it’s like there is no 1st or even 2nd gear and sometimes no 4th) and b): the “outside temperature was showing approximately 10 to 15°C higher than it was.

3) Other things to mention are: a) after driving a while (but not always), the “outside temperature” starts going back to normal and sometimes even the “check engine” light goes “off” & transmission would work fine, (transmission was brought back to almost new three years ago by Dr. Audi Mike Rooney in Los Angeles – good job).
b) several times, while “check engine” light is “on” I change from “D” to “N” and the light goes “off” to come back “on” as soon as I put it back on “D” (but not always)

. c) When I start the car in the morning (colder now) it works fine, unless I get stocked in heavy traffic and temperature gauge starts climbing close to 100°C then, most probably the “check engine” light would go “on”. But when I start the car after an hour or so being parked, the “check engine” light would go “on” almost immediately.
d) Lately when I start the car, sometimes the beep does not sound and the seat belt indicator goes on even if the belt is engaged.

e) Right before all this “confusion” started to happen, there were several things happening: e1) the “outside temperature indicator” would flash for a minute almost every time I would start the car (not happening lately). e2) the “ABS light started to come on by itself, put a brand new switch and problem persists. e3) I have to start the car several times, unless I give extra gas. e4) Cruise Control stopped working.
e5) The gear indicator lights on the dash for 3rd and 2nd, don’t go “on” when I start the car, but they do after driving a while.

I don’t know if all this things are connected or not, perhaps more than one thing is failing at the same time.

All suggestions appreciated
My thanks in advance for taking the time

Leo

sounds like you have a problem with your electronics. Engine and transmission are electronically controlled and depend on a variety of input sensors to work correctly.
Check your battery, the alternator incl. voltage regulator and the wiriing around the alternator. I`ve had some of the symptoms you described when my voltage regulator needed to be replaced (lights coming on, strange behaviour of instruments...)

Have you tried to pull the fault codes from the ECU? That`s should be the first step in diagnosing anything amiss with your cars brains - the computer usually has some idea what`s not working and will tell you via the fault codes stored in its memory. Do this first before changing any expensive parts....
Any Audi affiliate should be able to perform this. If you have no Audi dealer near where you live, you may do this yourself using VAG-COM software and an interface adapter wich can be purchased at www.ross-tech.com or off eBay....
Read more of this on the (great!) SJM site: http://www.sjmautotechnik.com/trouble_shooting/ecufv8.html

First of all thank you for replying so fast.
I didn't have much time this past week to do anything.
I did some of the tests and it gave me a 2231 code and something about a sensor G28 came out ot a friends computer.
So I guess that should be my starting point ...
Any suggestions ?
Should I perform any other tests ?
Thanks again
Leo

G28 is the Engine Speed Sensor, Audi Part Number 077 905 381A (however you can substitute 077 905 381). More info here:
http://www.audifans.com/twiki/bin/view/Audi/NoStartV8

2231 is the Idle Stabilizer Valve. This is the black Bosh part on the front of the engine, on top of the throttle body. You can remove it by taking off the three acorn nuts and gently dislodging it from the intake manifold (be careful of the gasket.) Now you can clean it with throttle body cleaner (not brake cleaner), which also has lubricant in it. Once you get it reinstalled, check for vacuum leaks; perhaps you get this fault code because the ISV can’t compensate for the vacuum leak.

Good luck,

- Jeremy

Thanks Jeremy and everybody. First problem solved: code 2231 is gone, the car is starting fine, as you said it was the ISV or in spanish: "Ralenti". I want to mention that a few days before doing this, I changed the ABS switch and drove the car fast enough for a while on an empty highway. Right after that the "check engine light" never came back on but after cleaning the ISV it really starts neatly.
Now, the ABS OFF light is still coming on very often and stays that way and also the airbag light comes on for one to one and a half minute every time I start the car, to go off after that.
I am starting to feel car's wires and connectors are getting pretty old, copper is sulphating (I hope I'm saying it correctly).
What would be the options :
Buy harnesses and change them, are they available?
Are they affordable?
Changing complete sections of cables and wirings including switches and connectors, little by little?
Yet another situation is the Outside temperature indicator still shows at least 10 centidegrees more than it should.
And the background illumination of 3 and 2 on the instrument panel display sometimes are off when I start the car but a few minutes later they start working normally.
But so far everything works just fine, that is why I think the cables/connectors are with sulphate or bad somewhere and ithat bothers a little bit everywhere.
What do you think ???
In any case thanks for your help.