1985-1998 [Subscribe to Daily Digest] |
[Profile/Gallery]
, Sun, 1 Jul 2001 15:04:38
Members do not see ads below this line. - Help Keep This Site Online - Signup
when DI/APC was incorporated. on the older units with ignition amplifiers(non-DI) the valve (metal case) had a case ground and two wires so some of these data may be old model info applying only to non-DI ignitions. Buzz is normal, These units are pulse devices one lead drives the 70 Hertz rate and above 2500, the Hertz rate changes to 90 hertz. Both are driven by the DI/APC module and actually modulate the turbo all the time the engine is running not simply a ON/OFF solenoid as before. Much better /finer control of the boost pressure.
Pin 2 is +12 volts when the ignition switch relay is energized. pin 1 goes to pin 10 on the Di/APC controller, pin 3 goes to pin 33 on the same device
input to the DI/APC is information from the knock sensor and the boost pressure sensor. When the knock sensor detects a pre-detonation (knock at 2500 or less) it signals the boost sensor to close the solenoid to Reference "R" and dumps pressure to the wastegate motor "W" thus opening the waste gate. Above this RPM the pressure switch comes into play and functions along with the knock detector the same way and limits boost output. You may be able to test the ohmage to the solenoid by picking pins 2-3 and pins 2-1 the resistance should be approximately 31 ohms. If you have a scope the pulse rate can be viewed at the DC scale 0-12V on the 0-120 hz range. if you scope the knock detector you will see this is on the AC scale normal 0-5 mvolts and with knocking induced see that it rises to 100 mvolt AC. If you don't have a scope you are pretty much limited to just simple resistance reading and listening to the buzz. HTHs on the theory of the solenoid operation
Your question: maybe I answered in the beginning the differenc is in the ignition system and controller- non DI two wires and a case ground.
2. Boost on your car should -depending on your operation altitude, sealevel it should rise to about the line between the yellow and the red at high altitude (8000 ft) you will go into the red about half way. This gage is a reference gage(measures against ambient) you will notice that with ignition on an engine off the needle sits just on the yellow/green line- that is your ambient reference Green is vacuum and yellow is pressure. If you wish to know exactly you are pumping, will need to tap into the manifold and apply an absolute pressure gage. Your car should boost 10.3 to 11.8 psi above ambient.
, Fri, 29 Jun 2001 13:52:50, Sun, 1 Jul 2001 15:04:38
No Site Registration is Required to Post - Site Membership is optional (Member Features List), but helps to keep the site online
for all Saabers. If the site helps you, please consider helping the site by becoming a member.
 |
 |
 |
 |
 |
