"Bernd D. Ratsch" wrote:
> Hey Shane,
>
> Yup...it's a V6. I haven't checked the MAP readings on my original one yet
> to see where they're at...but a gut feeling told me that this is the problem
> from the very start of the whole "Pinging Dakota" problem. (Along with a
> slightly too aggressive timing curve for the average daily driver.)
I hear ya - isn't that kinda wild to have 36-40 degrees advance almost all the
time? My scan tool reports the same thing - anytime the rpm's or mph are much
more than idling and low speed - it jumps way up there. I guess thats how they
get the magnum motors to get better fuel economy (vs LA blocks). It just don't
seem right considering they usually weigh over 4500 lbs. Have you found out
what the major contributing factor is to the spark advance? It looks to be
related to TPS, MAP, and/or VS as far as I can tell. I understand that the
magnum motors don't have a knock sensor and supposedly they sense knock via the
crankshaft sensor or something like that. I don't believe they are using
anything as I can't see much retard happening at all under heavy load. Maybe
just a little as the MAP changes drastically but not like it should. I've
watched the spark advance at the onset of pinging and it isn't changing -
therefore I don't think they are sensing knock at all. Whaddya think?
Latr,
Shane
ps - on a related note, I did find the magic point at which the system changes
from open-loop to closed-loop at first startup. Its the oxygen sensor voltage.
Everyone assumed it had to do with ECT but that didn't explain why it still
transitioned from open to closed-loop while the engine was still hot (at
startup). Now I know its not related to anything but O2 voltage and most
specifically - when it makes that first transition past stoich. Cheers!
-- '96 IndyRam-HisIndy-MPI/TB/Pulleys/Coil/Wires/CompTAs '96 IndyRam-HerIndy-numbered(#142)"Track Truck" '74 Triple-Black Dodge Challenger Rallye 360 home-brew EFI R&D vehicle '68 Black Corvette Convertible 427 (For Sale)
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