Does anyone know if the 420A motor pulls timing if it detects knock (detonation) like the 4G63??????

We have a knock sensor, so I would assume that the ECU uses it to sense detonation and pull back timing. I couldn't find any specifics in the shop manual.


Corbin
'95 ESI-T
HRC + FMIC
http://members.nbci.com/cbehnken/

asked a shop that works on our motors a lot. The guy said that it does retard timing if it senses detonation but it is limited in its duties to do that. In other words, the module is only equipped to do minor retarding. I dont know if this information is correct, hence it came from a machine shop. Take it with a grain>

Somebody with a datalogger should throw some 87 octane in the tank, 5 range plugs and crank the boost a little to see how capable the PCM really is at retarding. Too much retard as well as too much advance will cause detonation so at some point it wouldn't be effective.


Stan2gnt
Stan2va@aol.com
95 Talon 420A-Turbo
Former and future nitrous user

Been there done that :)

On the dyno, I pulled the vacuum to my fuel pressure. It retarded my timing big time. Armond was there and saw it too. I lost 60hp no joke. Yes timing gets pulled. I will do it with a datalogger again though so I can see exactly how much is really being pulled. I currently use the DIS-2 with 6deg retard which has a lot to do with how I run 18psi ;-)

MuRiX
97 Eclipse GS HRC Stage II
And a whole lot of other mods...
A.D.P.
http://murix.home.icq.com/index.html