Throttle position sensor/circuitry checking w/resp. to poor fuel econ.

[motogo1]

I would have to say Bentley is far from 100% accurate. When I first got my
S4 about 4 years ago, I did some testing on the TPS trying to chase down a
problem. I don't remember which test it was, but according to Bentley the
TPS was no good. Replaced with new TPS...tested exactly as the old one did.
Problem I was chasing was not remotely related to the TPS.
    FWIW, my 200 seems to down on mileage a bit. I'm thinking of getting the
injectors cleaned. Can the O2 sensor affect mileage? This has probably been
covered before, but I just don't remember.
    I may just go out and check my TPS on the 200 and see how it compares to
your tests. I'll report back later.

Gary Martin
94 UrS4
91 200 TQA

----- Original Message -----
From: <benswann at comcast.net>
To: <200q20v at audifans.com>
Cc: <quattro at audifans.com>; <benswann at comcast.net>
Sent: Tuesday, September 09, 2003 7:44 AM
Subject: Throttle position sensor/circuitry checking w/resp. to poor fuel
econ.


> One of the suspects I've been trying to rule in/out is the throttle
position
> sensor and circuitry.  According to Audi/Bentley Sec 24-120-2 the voltage
> between pins 1 and 3 must be 4.5 to 5.5 volts.  On my car the reading was
> 3.3V.  According to Bentley that means faulty wiring or bad ECU.
>
> Having access to another unchipped '91 200 20V, I ran same test - voltage
> between pins 1 and 3 is 3.7V  which is apparently not in spec. either.
>
> Is the manual 100% correct.  Is this a coincidence and both cars have a
> problem?  Is there something that goes awry inside the ECU?  I don't see
how
> this would be wiring as I get a consistant reading and have not found any
signs
> of wire damage.
>
> As I continue to attempt to track down what I perceive to be a problem, I
am
> wondering if this is a common descrepancy.
>
> Not to muddy the waters here are some other things checked/verified:
>
> TPS checks OK/in spec. except resistnce between pins 2 and 3 varies from
.9k to
> max at WOT ->2.7k - Recent question from other lister enquired if this is
in
> spec or not as Bentley not clear, but indicates resistance must increase
to a
> maximum of 3600 ohms.
>