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RobP
06-03-2002, 10:39 PM
What scanner readings should I see on the CCP purge? On my 89RSZZ4TPI anything over 5% throttle induces at least 99.5% purge/cycle. Does this sound normal?
I'm still getting massive knock counts and timing retard on anything over 20% throttle. Good ignition stuff and good fuel pressure as proven by FP gage sticking out the hood.
Skweezn87
06-04-2002, 03:40 PM
All that does is allow gas fumes be circulated into the motor...

Now.. what kinda timing are running? compression?
Can you reburn your own chips??
RobP
06-04-2002, 10:04 PM
ZZ4 is 10:1 compression, 93 octane, 6 deg adv timing. It's not a chip problem cause the car has run pefectly before, same chip. I got the Helms out and am gonna check the knock sensor for proper voltage. I may try bumping the initial timing back to zero. However the scanner never shows more than 35 total advance.
Rob
WS6 VERT
06-04-2002, 10:35 PM
Your not burning oil or anything are your?
RobP
06-05-2002, 12:02 AM
NO! It better not be LOL! No oil consumption at all. I did the knock sensor test from the Helms Manual:
Tap on right exhaust manifold while observing knock signal. "Scan" tool should indicate knock while tapping on manifold.
Does it?
Yes
System is operating properly.

The only other two things I can think of is this, the car was running way rich. Could I have excessive carbon build up on the piston tops? Would this cause detonation all the time or under load only?
Or, could I have an injector that is malfunctioning under heavy load/pw causing a lean condition in one cylinder? Thus causing one cylinder to ping and activating the knock sensor?
Just rambling thoughts I come up with while I try to get to sleep at night or daydream at work.
ragtop88
06-05-2002, 12:37 AM
You try retorqueing the knock sensor...maybe it was tightened down too far making it too sensitive? Also why not pickup a tank of high octane race gas and see if it is real knock or false knock....if it still knocks with race gas then its probably false....just some more ideas to help your daydreaming...
RobP
06-05-2002, 09:11 AM
Race Gas in the Keys? HAHAHAHA
I'd have to drive to the NHRA track in Homestead, 3 hours away to even think about smelling race gas! Closest 1/4 track is West Palm.
The knock sensor has been in the engine since new, about 30/40K miles ago. Doubt it would have tightened up. Maybe some octane boost snake oil to test with.