[V8] 1990 V8 auto transmission issue

[Bill Braden]

Tony,

 

I have a 1990 V8 (110K miles) that shifts down to limp mode at about 2K RPM
if you let up on the accelerator.  

 

According to the mechanic the code was a trans solenoid failure.  He checked
with ZF and apparently was told that solenoid failure is very rare and that
it was likely a wiring harness problem.

 

The pan was dropped and the solenoid positions were changed and the external
wiring harness was replaced with another used one.  The problem still
exists.  I haven't yet taken it back in to see what the code is now.

 

Am I on the right track or should I be looking at the multifunction sensor
per your comments below?

 

I love this car and it runs great other than the downshift problem.  I just
had the entire rear suspension redone (re-bushed, shocks, & brakes) and new
front brakes with new UFO rotors so I would hate to bail at this point.

 

Thanks.

 

Bill

 

 

 

Message: 4

Date: Sun, 10 Jun 2012 18:23:55 -0500

From: "Tony and Lillie" <tonyandlillie1 at earthlink.net>

To: "v8audi" <v8 at audifans.com>,           <toml99 at todomundo.com>

Subject: Re: [V8] 1990 V8 auto transmission issue

Message-ID: <E09E492D18D24DDBB7263CF67F870566 at tfh5lqoxlbb5rh>

Content-Type: text/plain; format=flowed; charset="iso-8859-1";

                reply-type=response

 

To the original poster,

 

One other thing that is common to cause a limp mode is a failed/failing 

multifunction sensor on the side of the transmission. BTST and repaired 

several times.

 

You will know limp mode by the display of gear selection in the dash all 

lighting up at once, as opposed to indicating a single gear selected.

 

Tony