Timming procedure fot the Q
Timming procedure fot the Q
Can someone help me with the timming procces for the Q, I need to adjust my CAS and want to make sure I do the process correctly, Thanks.
Run a plug wire between the #1 coil and the plug, and place an inductive pick-up from a timing light on this wire. Timing marks are on the balancer. Marks go from 0-15* in increments of 3* if I recall right. Hopefully someone can verify. Rotate the CAS till you get the desired time. Don't advance more than 17-18* BTDC. 15* is nominal. If you have a nifty timing light for DIS ignitions, you can just measure off the wire going to the ignitor and not have to access the coil.
Well, the engine rotates toward the driver-side...crankshaft and camshafts. Since you want to advace the timing, and have the spark happen sooner, you need to rotate the CAS toward the passenger-side. Rotate the CAS 2* couterclockwise (facing the engine), and the ECU will think the #1 piston is at 15* BTDC when it's actually 17* BTDC, and fire the #1 plug.
EDIT: OOOOPS, sorry I screwed up. The cams rotate at 1/2 the speed of the crankshaft, soooooo if I'm thinking straight you need to rotate the CAS 1* for every 2* of advance. All should be fine if you're using a timing light. Careful...that's not a lot of movement!
EDIT: OOOOPS, sorry I screwed up. The cams rotate at 1/2 the speed of the crankshaft, soooooo if I'm thinking straight you need to rotate the CAS 1* for every 2* of advance. All should be fine if you're using a timing light. Careful...that's not a lot of movement!
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Q45tech
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- Car: 1990 Q45 342,400 miles 22 years ownership with original engine
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As a place to start looking at the CAS slot the center screw should be approximately to the right [at most 2/3] of the midpoint.
As I remember the slot has over 40 degrees of adjustment......fine and tedious proceedure to get it exactly at 15 BTDC........when the coolant temp is at or just above 176F and idle speed is correct............because the ecu uses timing trim to vary idle speed.......lock this out by removing the connector to IAC.
As I remember the slot has over 40 degrees of adjustment......fine and tedious proceedure to get it exactly at 15 BTDC........when the coolant temp is at or just above 176F and idle speed is correct............because the ecu uses timing trim to vary idle speed.......lock this out by removing the connector to IAC.
Quote »lock this out by removing the connector to IAC.[/quote]
Thanks Dennis, this is how it is done on my other Nissan, you have to hold the throttle open @2000 rpms for 45 seconds, rev it up 3 times past 2 grand, then shut it off and disconnect the TPS and the IAC plug, make your adjustments, then rev 3 more times to past 2grand, shut off and recconect everything and you are all set, glade the Q is a lil easier.
Thanks Dennis, this is how it is done on my other Nissan, you have to hold the throttle open @2000 rpms for 45 seconds, rev it up 3 times past 2 grand, then shut it off and disconnect the TPS and the IAC plug, make your adjustments, then rev 3 more times to past 2grand, shut off and recconect everything and you are all set, glade the Q is a lil easier.