93 UrS4 hesitation problem

[Brett Dikeman]

At 1:28 AM -0400 4/30/02, Audisport8 at aol.com wrote:

>Has anyone experienced really bad cutting in and out under
>hard acceleration?  I can't tell if it is detonation or a spark plug problem.
>I replaced the plugs once already because they were fouled so badly.
>This only happens under hard acceleration.  Please help!

Any codes from the ECU?  I doubt it's detonation, unless you've been
running below 91 octane gas, or have some really oddball problem.

This sounds more like a split hose, or a loose hose clamp...the
split/loose hose flaps open+closed under boost like a kid making
motorboat noises, causing a loss of metered air that makes the car
buck severely.

But, that's a pretty wild a$$ guess; could be ignition related,
aren't there some problems with the coilpacks on S-cars? I only know
the 3B well, not the AAN...lots of differences between the two, and
ignition is one biggie...

   I'd try pulling codes from the ECU...if you get a bunch, write them
down, clear the ECU, and drive the car again, then dump the codes a
second time and compare.  Sometimes, faults can be years old from
when someone accidentally unplugged this or that while working on the
engine, then tried to start the car, and the ECU noticed it.  Heck,
happens to me all the time, and I'm always the goofball that did it(I
left my MAF unplugged once, figured that out about 10 feet out the
driveway, forgot to clear the code, my mechanic found it a year or
two later tracking something else down.)

see:
http://www.sjmautotechnik.com/ecuf20v.html
for how to dump the codes.

BTW, your car most likely never came with a bulb for the check engine
light.  Installing one involves pulling the dash, which may be easier
on the S cars, but its a royal PITA on the 200q20v, for example, with
the wheel on(and taking the wheel off involves messing with the
airbag.)

I just swapped the bulb over from the door-open bulb, too lazy to go
buy one :-)

If you put the bulb in, you'll see the instant a fault code gets
stored...and at least on the 200q20v, you can read out fault codes
via that bulb, instead of having to wire up an LED in addition to the
jumper(and in a pinch, all you need is a paperclip to pull the codes,
how MacGuyver is that! :-)

If the above doesn't help much and nobody else here straightens you
out, try posting to the S-car list, which is now hosted here on
Audifans(welcome, guys!)  I don't know if they set themselves up to
be posting-by-membership-only or open to all; you can always just try
posting to s-car-list at audifans.com and see if it bounces
back(actually, even if they're "private", most likely it'll get held
for admin approval, and if Darin sees it, he might approve it.)

Brett
--
----
"They that give up essential liberty to obtain temporary
safety deserve neither liberty nor safety." - Ben Franklin
http://www.users.cloud9.net/~brett/