Ignition trace query

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roadandtrack
Newbie
Posts: 4
Joined: Wed Jul 05, 2017 10:46 am

Ignition trace query

Post by roadandtrack »

i am attempting to identify poor/erratic running with a Toyota 4AG race engine using a Motec M4 computer. Almost every part on an around the engine is new, yet i have erratic operation which is sometimes on 1 cylinder and then it moves to another cylinder. i am using exhaust temperatures to work out which cylinder is not working properly. i have done extensive mechanical tests and ruled out problems from that source

i have been unable to work out how to make the scope view all 4 cylinders at the same time and separate the signals as they all seem to be vertically beneath each other??. is there a fix for this??

I attach various traces of the secondary ignition where i have changed the ignition coil as i suspected that as being part of the problem . i nearly all cases, the voltage rises. can anyone offer some plausible explanation for this?

many thanks, Terry
Attachments
bosch transformer coil cyl4.psdata
(19.2 KiB) Downloaded 445 times
generic oil filled coil cyl2.psdata
(16.9 KiB) Downloaded 419 times

speck
TwoWaves
TwoWaves
Posts: 63
Joined: Sun Mar 25, 2012 5:20 am

Re: Ignition trace query

Post by speck »

How about turn your no.of samples up and put some more time on the screen. 500ms/div -500MS
and repeat

speck
TwoWaves
TwoWaves
Posts: 63
Joined: Sun Mar 25, 2012 5:20 am

Re: Ignition trace query

Post by speck »

speck wrote:How about turn your no.of samples up and put some more time on the screen. 500ms/div -500MS
and repeat
5MS sorry

roadandtrack
Newbie
Posts: 4
Joined: Wed Jul 05, 2017 10:46 am

Re: Ignition trace query

Post by roadandtrack »

thanks, if you open the files you can move back and forth

yes, i can try logging for longer

speck
TwoWaves
TwoWaves
Posts: 63
Joined: Sun Mar 25, 2012 5:20 am

Re: Ignition trace query

Post by speck »

roadandtrack wrote:thanks, if you open the files you can move back and forth

yes, i can try logging for longer
yes I know. Your settings are poor. Also include primary current.

roadandtrack
Newbie
Posts: 4
Joined: Wed Jul 05, 2017 10:46 am

Re: Ignition trace query

Post by roadandtrack »

define "primary current" please so i can make sure i'm logging what you expect

speck
TwoWaves
TwoWaves
Posts: 63
Joined: Sun Mar 25, 2012 5:20 am

Re: Ignition trace query

Post by speck »

roadandtrack wrote:define "primary current" please so i can make sure i'm logging what you expect
How about looking it up in "guided tests"

roadandtrack
Newbie
Posts: 4
Joined: Wed Jul 05, 2017 10:46 am

Re: Ignition trace query

Post by roadandtrack »

here are some files. any help appreciated

what i can see is...
voltage varies a lot across all 4 cylinders despite having all new parts and plugs with identical gaps. changing coils increases the peak, but still i get this big variation. engine compressions are all identical
i changed the coil saturation time from 3 to 6 msec and that got it up to about 6amps and increased the peak voltage output. engine sounded better but still randomly not running nicely on all 4.
Attachments
cylinder3.psdata
(8.95 MiB) Downloaded 413 times
Coil Curent and Coil Sec motec DELL=6 3000rpm engine sounds like 3 cylinders.psdata
(10.22 MiB) Downloaded 403 times

speck
TwoWaves
TwoWaves
Posts: 63
Joined: Sun Mar 25, 2012 5:20 am

Re: Ignition trace query

Post by speck »

roadandtrack wrote:here are some files. any help appreciated

what i can see is...
voltage varies a lot across all 4 cylinders despite having all new parts and plugs with identical gaps. changing coils increases the peak, but still i get this big variation. engine compressions are all identical
i changed the coil saturation time from 3 to 6 msec and that got it up to about 6amps and increased the peak voltage output. engine sounded better but still randomly not running nicely on all 4.

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