[V8] new problem - 4.2Q tranny

Jeremy Ward jward at mti-interactive.com
Wed Nov 17 11:19:45 EST 2004

Hey Carter, sorry to hear about the problem you have been having.  I
think this one is related to the last problem you had.  Under most
conditions, when the car goes into limp-home-mode, all of the segments
light up orange (PNRD321), but under other conditions they all go black,
which is what you are experiencing.

I had an issue with the idle switch (located inside of the throttle
position sensor) not seeing a 'closed' condition. When I would drive the
car and take my foot off of the gas, it didn't know that I had done so,
and therefore didn't make a correction to the fuel; it felt like I was
driving a stick-shift and wound it up, then took my foot off the gas w/o
pressing in the clutch.  This caused my car to go into limp mode with
the segments *not* lit.  The root cause in my case was a bent cruise
control rod (happened when the transmission shop reinstalled the
transmission), combined with filthy butterfly valves inside the throttle

I would recommend that you pull the codes (very easy to do) and the car
will tell you what it thinks is wrong with the engine / transmission.
Instructions can be found on Scott's website here:

In my case, I was getting 2121 on the engine (idle switch) and 2243
(Consumption Signal) on the transmission.

If your problem is the same as mine (seems very likely) then it is a
matter of finding out what is hindering the throttle from returning to
all-the-way-closed.  On the front of the throttle body, there is a
little 'arm' that is bolted to the end of the shaft that connects to the
throttle cable at the other end.  With the engine turned off, find this
leaver and lift up on it; this will simulate stepping on the gas.  Now
let it return to rest and push down on it, forcing it to be 'more
closed' than it is at rest.  If you hear a CLICK from the TPS, you will
know that something is preventing it from closing all the way on its

Hope this help,

- Jeremy 

BTW, 'Consumption Sensor' and 'No Speed' errors from the transmission
are the only 2 codes that will cause the car to go into limp mode, W/O
causing the PRND321 segments to light up.  (source: repair manual)

-----Original Message-----
From: v8-bounces at audifans.com [mailto:v8-bounces at audifans.com] On Behalf
Of Carter Johnson
Sent: Wednesday, November 17, 2004 5:20 AM
To: v8 at audifans.com
Subject: [V8] new problem - 4.2Q tranny

New problem surfaced last night;

First, I noticed that the indicator light for which
gear the tranny was in was no longer lit.  I was
driving around 40mph, so I didn't notice that the car
also seems to be stuck in 3rd gear - lots of slippage
at takeoff and then winds way up - 65mph is over 3,000
rpms.  I can't manually shift the tranny anymore, and
the mode changer also doesn't appear to work.  Is this
the fabbled "limp home" mode?  I'm dropping off the
car today at my long-standing mechanic, who I think is
already fearing the car.

This car is a ball.  Every day I've driven it so far,
something major has happened or broken.  Still love
it, though....

Any help is appreciated.  Thanks in advance!  


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