View Single Post
2jmotorsports 2jmotorsports is online now
Perpetual Reassembler
 
2jmotorsports's Avatar
 
Join Date: May 2010
Location: Orange County
Posts: 1,039
Garage
Dwell Meter vs Multimeter for FV Duty Cycle

1983 SC running CIS with Lambda

I am preparing to tune my frequency valve duty cycle (for CA emissions testing) and wanted to check with you guys which of these is the better tool for that job.

I have this handy dandy Fluke clone from Amazon:

https://www.amazon.com/AideTek-VC97-Multimeter-Capacitor-Frequency/dp/B008GTEZPI/ref=cm_cr_arp_d_product_top?ie=UTF8



At the moment my mixture is set by ear, pushing/pulling on the air sensor arm by hand to find the sweet spot where it runs well. It is probably set on the rich side at the moment but runs great. Anyway I connected the multimeter to the green wire on the test port and while it warms up it reads a looping duty cycle of 50-80% every few seconds until it reaches operating temp, then it reads a fluctuating 75-82%

Based on this I think the multimeter is doing its job. I mean, the number on the display is a tad jumpy but its readable.

I also have this OG dwell meter leftover from my VW bus days.

https://www.amazon.com/Actron-CP7605-Tachometer-Voltmeter-Analyzer/dp/B00062YUUS/ref=cm_cr_arp_d_product_top?ie=UTF8



It still works. When I connect it, the dial rises to some value and slowly sweeps back and forth within some operating range but I have no idea how to read it. Do I use the 6 cylinder scale or use the 4 cylinder scale as indicated in some prior threads?

Thanks in advance!
__________________
Jose - 1983 911SC Coupe
Instagram: @joe_engineer
911 D I Y Blog: joe-engineer d o t c o m
D I Y Vids: https://www.youtube.com/joeengineer

Last edited by 2jmotorsports; 11-11-2019 at 07:16 AM..
Old 11-10-2019, 06:46 PM
  Pelican Parts Catalog | Tech Articles | Promos & Specials    Reply With Quote #1 (permalink)