Problems on the A4 continue...

[Rob Andrews]

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I've sent this to a few friends...I'll copy and paste here.
If anyone has anythoughts please email me direct, I dont always ready
all the digests...



I'm sending out a blanket email to a few people here....
I've talked to all of you to some extent with regards to my problem and
I'm at my wits end.  I'm willing to pay people to come out to my place,
etc. or just help me figure out what is going on with car.  I really
don't want to take it to some other local shop in town because I fear
I'll just be out money and they'll be just as dumbfouned I am.  Long
story short to recap....
Long term Fuel Trim Rich bank 1 and bank 2.  Codes 17535 and 17537
Watching long term fuel Trim, both banks are right about -20%.  Short
term fuel trim for both banks are behaing identical to each other and
range from rich to lean depending on load/etc.
Here is what I have replaced on the car
MAF
plugs and wires
FPR
O2 sensors in the front (before cat)
Engine coolant temp sensor
Throttle body
Fuel evap canister
Resealed all intake gaskets i.e. manifold to head, throttle body to
manifold.
I've checked all vacuum hoses for leaks.
I've looked at fuel hoses from rail to tank to see if there are any
crimps...doesn't appear so.
Checked fuel pressure at idle, around 70psi.  Checked it after engine
shut off, in the 30-40 range.
I've watched cam timing on block 91?  and at idle is about 0, and under
load about 21.  Ignition advance seems right on par compared to other
2.8s

Here are parts I find interesting which may or may not be key in
diagnosis...
Both banks when watching short term trim behave identical, leading me to
believe it is 1 common problem i.e. like fuel pressure instead of maybe
have and injector on both banks failed (which would be rare)

My long term trim used to around -25.  When I changed and put a new FPR
in it, it is now around -21 and -20 for bank1 and bank 2.
I don't know if that is indicative of anything.

In vag-com I have watched MAF values and they are on par with other
known functioning 2.8s, the air intake reading seems accurate, the
coolant temp reading the ECU sees also seems accurate.
02 sensor voltages check out OK, and the heater circuits appear to work.


Help!  I'm desperate!  I'll pay you...bake you goodies, paint your
house, something!




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Rob Andrews
99 A4 2.8QS   83 Ur-Q
www.robsaudiworld.com <http://www.robsaudiworld.com/>
Visit my new web page!


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