WHY??? analog dwell meter?
 

I can't seem to find an analog dwell meter. I purchased a very expensive multimeter from auto parts store. I was told it should work the same. why are people saying that you need analog??? just curious before I get oil and crap all over new one.... I am trying to test oz sensor and fv duty cycle on 81 sc.
:cool:

Advance Auto or Auto Zone have cheap analog ones on the shelf. Does the multi-meter you have provide a dwell function? I did not know they had them. I have a $50 MM and would love to know if it has dwell on it.

Sending PM now to you.

it's easier to read a needle that moves very little than a digital display that's forever changing. at least that's why i like a analog timing light. i had a digital snap-on light for about a week and gave it back.

speedy,

The ECU dithers the duty cycle of the FV back and forth over stoich. The swing of the needle, range and the frequency are important in diagnosing the system. Digital dwell meters are harder to read and some have an unknown dampening factor, in which case you lose this information. Several listers have reported problems with new analog meters that are self powered or do not have separate 12v + and - connections. Find an old guy and borrow his or buy a used meter for a few dollars.

i found mine on fleabay craftsman new in box paid about 30 ..... dwell, amp volt ...

called engine analyzer i believe .......

Steve ......

+1 John..
Guys, just make sure you don't use an older analog voltmeter etc. on any computerized circuits. The low resistance in these meters can fry electronic components..:(

thanks guys... I will be returning my fancy multimeter its nice but I am happy with my 30 bucker one. has anyone used this one before...found it on amazon.


psalt, john walker... I have seen your posts on other threads, I know I have read so many over and over lately. I am looking for a little advice.... I am have a problem with my 81 sc. starts great runs great until about 20 mins of driving... my idle starts to hunt but I lose power and right around 3000 rpm. when I take my foot off the gas it feels like there is a lot of compression and its like someone is applying the brakes. when I get to a stop light the engine wants to stall major idle hunting. thank you guys for all you posting it has sorted me out to understanding the basics. I went to check my fuel pressures but found that valve is leaking more like pissing out fuel so after six places of checking for parts I was unable to find the right brass fitting.... any ideas? so far I have checked tpv and seems ok checked additional 15' switch seems ok check for vaccum leaks not 100% confident so I will work on that a little more. I have checked relay on lambda seems ok I checked the cdi seems ok I am sure the co and pressure are good because it was just at shop and after a 5000 + bill I am scared to take it back.... any other suggestions???? I am working on getting a dwell and fuel pressure guage fixed.
thanks














http://images.amazon.com/images/G/01/richmedia/images/cover.gifhttp://forums.pelicanparts.com/uploa...1297556570.jpg

the lambda relay that powers the computer gets 12V from the domelight fuse. do the domelights work? unplug the relay when the car is running and see if the idle gets a lot rougher. it should if the system was working. without the frequency valve fuinctioning, it kinda feels like you're dragging an anchor.

thanks for the help john.... next time I am in seattle you get a case of canadian beers.

I actually thought from reading other posts that I would pull relay and see what happens... well I remover pass seat and drove around when the rough running happen I pulled over and and pulled relay....it actually smoothed out idle humting and sounded better. I could hear a click in the relay as I plugged it back in everything would seem better until a minute back on the road and then the return of rough idle, power and drag. I tried this numerous times same results. I did have a problem with fv not buzzing. I played with connection with engine running it would go on and off I believe I need to change the connection. but how does this affect idle hunt? and power loss?

thanks

somebody probably didn't know it was not working and cranked up the mixture adjustment to compensate. they go way lean when the FV doesn't work. so when it kicks in, you get way rich and a rich surge. anyway, check the plug on the relay for broken a wire, corrosion, terminal pushed out, the relay itself, the dome light fuse, the connector on the rear shock crossmember, water entry into the relay and computer, etc.

speedy,

The first step in finding a problem with the lambda system is reading the duty cycle from the test port. It will tell you immediately if the system is working as designed. You can use extended leads to have someone read the meter while driving to see if your problem is a result of an intermitent fault. Sounds like you have a heat related problem, have you tested the main temperature switch on the right chain case ? A bad coil or the green wire from the dist to CDI can also give heat related drivability issues.

thanks again guys.... I feel like some of my hair is already growing back.... I will have a look at all the fv related issues that john had mentioned. paul you are right I know for sure its heat related because she drives great until she gets hot. I am not sure how to test the coil or the cdi. I have bently but very basic and I did many searches for "how to test a coil" and nothing. I have tested cdi according to benlty man. and it show power and it seems ok.I have not checked 35'switch but I will thanks so I will get back to the garage today and see what I can find.

That is the dwell meter I purchased from the local big name parts store. Works fine.

As John says check the connection at the back of the engine on the cross member. A guy in Houston last summer had the same type of frequency valve issue and it turned out to be that connector. His connection to the F valve would break when it was hot outside and when the car was warmed up.

Good luck.