scan tools and WOT

[David A. Cooley]

At 08:25 AM 10/14/98 -0500, you wrote:
>
>I made an interesting observation while at the track this past Saturday.
>I made 4-5 runs with Diacom recording data.  Then I made 5-6 runs with
>the Diacom disconnected.  Guess what?  I was both quicker and faster
>by .1-.15sec and 1mph with the Diacom disconnected....
>
>Wonder why????  This is on any '87 TPI/MAF motor.  Is the ECM that slow
>that it can't optimally control the motor at WOT while transmitting
>data?

Diacom is probably putting the car into 10K ALDL mode.  This fixes timing,
raises idle etc so the tunings are no longer optimal.  Timimg is no ;onger
varied by the chip according to the tables *or* knock sensor.
Might check with Rinda Technologies and see if they have a way to allow the
ECM to be in normal mode while Diacom is linked.
Later,
Dave

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           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.
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