[Fwd: New member needs help]

[David A. Cooley]

Actually, looking at the cal for my 95 lesabre, it *should* stay closed loop
at WOT.  However, it should be a bit richer, like 12.7:1...
It looks like it's leaving PE mode.  Is this an aftermarket chip or the
stock cal?

-----Original Message-----
From: J Norris <jwn at sgi.net>
To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
Date: Thursday, November 19, 1998 1:47 PM
Subject: Re: [Fwd: New member needs help]


>That's not my problem.  Mine is going into Closed loop at 4.85 volts TPS.
At
>this point it is trying to maintain a A/F ratio of 14.7:1 or 450mv on the
O2
>sensor.  Hence a lean condition at WOT.
>
>David A. Cooley wrote:
>
>> This is from what I have seen on the 84-87 Buick Grand Nationals...
Looking
>> at the cal for the 85 shows a limit for TPS high and TPS low errors...
>> Several other parameters have to be met to turn the check engine light on
>> and set the code, but coming out of closed loop may be part of the error
>> (The computer assumes the sensor is shorted and goes open loop with fixed
>> fuel/timing etc)
>>
>> -----Original Message-----
>> From: J Norris <jwn at sgi.net>
>> To: diy_efi at efi332.eng.ohio-state.edu <diy_efi at efi332.eng.ohio-state.edu>
>> Date: Thursday, November 19, 1998 11:38 AM
>> Subject: Re: [Fwd: New member needs help]
>>
>> >Very interesting David.  How do you know this?  This seems to be exactly
>> what my
>> >car is doing.  The GM service manual says nothing of a high voltage.  Do
>> you
>> >know where you read this?
>> >
>> >Jason Norris
>> >
>> >David A. Cooley wrote:
>> >
>> >> At 10:18 AM 11/14/98 +1100, you wrote:
>> >> >>
>> >> >Doesn't ECU read high tps as large throttle opening and richen up
>> >> >accordingly?
>> >> >I don't understand
>> >>
>> >> It does to a point, but it also has a certain level that it uses to
>> >> determine if the TPS is shorted or open... Depending on the car,
Usually
>> it
>> >> goes to about 4.6-4.7V as normal operation... above that it thinks the
>> >> wiring or the TPS is shorted.
>> >> Later,
>> >> DAve
>> >>
>> >> ===========================================================
>> >>            David Cooley N5XMT           Internet: N5XMT at bellsouth.net
>> >>      Packet: N5XMT at KQ4LO.#INT.NC.USA.NA   T.A.P.R. Member #7068
>> >>        I am Pentium of Borg...division is futile...you will be
>> approximated.
>> >> ===========================================================
>> >
>> >
>
>