[Shotimes] tranny issue (maybe)

[Adam Parrott]

Jason,

While it is technically possible that your converter may be playing tricks
on you at idle, I wouldn't look to it as the source of your idle hunting
problem.  Aside from a set of (unused) 2nd gear lock/unlock functions in
the H3Zx code, neither the '93 H3Zx or the '94-'95 D4U1 PCM programs make
any provision for converter lock in first or second gear (or IOW, the
converter is always unlocked in first and second gears on the Gen 2 ATX).
Even so, it is technically possible that a short or other electrical
gremlin is playing occasional havoc with the converter's lockup solenoid in
the valve body, causing erratic lockup while at idle.  Highly inprobable
(and very unlikely), of course, but still technically possible.  ;)

BTW - have you checked to make 100% sure that the compressor is not
engaging when this idle drop happens, despite the fact that the EATC is not
in a compressor-use mode (i.e. clutch sticking, etc.)?

As for the converter behavior that you described while at highway cruise,
it's perfectly normal.  As I noted previously, the converter remains
unlocked in both first and second, and will not lock in third or fourth
until a) the coolant temp (as indicated by the ECT sensor) has reached a
certain, predefined temperature (also referred to as "Torque Control" in
EEC circles), and b) sufficient throttle position and speed have been
achieved for that particular gear (third and fourth gears each have their
own set of lock/unlock tables that specify when the converter should lock
or unlock based on TPS and VSS sensor feedback).

IOW, the behavior you described is normal.  ;)

Sorry for the long-winded reply.  Hope it helped a wee bit.

Adam


----- Original Message ----- 
From: "Jason Hartberger" <at3hartberger@mail.com>
To: "Shotimes Mailing List" <Shotimes@autox.team.net>
Sent: Friday, November 05, 2004 10:55 AM
Subject: [Shotimes] tranny issue (maybe)


Hey guys, my engine has been acting kinda weird lately - actually, ever
since the tranny swap. When at idle, the engine will normally rev fine at
about 900 rpm (I have ted b's chip in), but occasionally (every few minutes
or so worth of idling), the engine will... I guess grab? the RPMs will dip
to about 700 for just a tiny little while and the car will start to lurch
forward a little if I'm not on the brake. it's like the torque converter is
starting to lock up for just a little while... like a tenth of a second,
but then it'll back off and everything will be ok. I do have a brand new
AXODE in there so it's under warranty, but is there something wrong with my
tranny? I'm not too worried about it as it hasn't caused the engine to
stall yet.

While I'm on the subject... when I'm at highway speeds, after letting off
the throttle to slow down and pressing on it again, the engine will rev up
like it should, then it goes down about 300-400 rpm, apparently as the
torque converter locks up. it stays down until it happens again the next
time I get on the throttle (even ever so slightly). Is this normal? it
happens every frickin' time I let go of the throttle... shouldn't the
converter stay locked up? or not? I really don't know much about ATXs....
please help!

Jason