Author Topic: mis-fire  (Read 9500 times)

Offline Seight-v8

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mis-fire
« on: June 04, 2010, 08:30:43 am »
hello all,

is it possible to detect a mis-fire from the logging in vemstune???

Still finding my way...and need to know if its possible to spot one...

As my knock readings on idle are bouncing all over the place....and not sure if this is a sign of mis-firing...

Engine feels like it might be mis-firing every few seconds....but not sure.

cheers

scott
Engine:Rover V8 4600cc
Vems Firmware:V1.2.38, GPS, SDcard, LCD & Dual lambdas, Wasted spark, 36-1 trigger, Cam Sync & Bluetooth serial.

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

Offline dnb

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Re: mis-fire
« Reply #1 on: June 04, 2010, 01:07:46 pm »
Yes, I think I have a way if your datalogs include the tooth timing info.  Post up a log and I'll do the calculations.

Offline Seight-v8

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Re: mis-fire
« Reply #2 on: June 05, 2010, 10:06:39 am »
hello dave,

took me  a while, but i just made my own members page.....

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

So uploaded some pics & latest config to my virgin account...

Still its in progress....and will add some more stuff soon.

cheers

scott
Engine:Rover V8 4600cc
Vems Firmware:V1.2.38, GPS, SDcard, LCD & Dual lambdas, Wasted spark, 36-1 trigger, Cam Sync & Bluetooth serial.

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

Offline Seight-v8

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Re: mis-fire
« Reply #3 on: June 06, 2010, 01:28:54 pm »
still trying to understand why at idle my logs show the spark angle changing from 5-8 degs.....

yet it should be 9-14degs as set in the spark table....

still un-decided if this is a mis-fire...as nothing else is changing in the log for the spark angle to change....

thought i would see...a constant spark angle...unless i have a problem coil pack??

scott
Engine:Rover V8 4600cc
Vems Firmware:V1.2.38, GPS, SDcard, LCD & Dual lambdas, Wasted spark, 36-1 trigger, Cam Sync & Bluetooth serial.

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

Offline dnb

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Re: mis-fire
« Reply #4 on: June 06, 2010, 02:59:26 pm »
Have you got ignition ratard based idle control enabled?  This would give strange log readings.

Offline MGV8

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Re: mis-fire
« Reply #5 on: July 10, 2010, 06:28:00 pm »
Hi Seight-V8

Is it possible to get a copy of your config file. I am trying to get my MGB V8 running with Vems - and have problems with getting ignition right. Started with ignition (waste spark with two Bosch coils), still running cabs.
Engine is running but not as good as on dizzy :(

Thanks Søren - Denmark
MGB Roadster 4.0 Rover V8 - Vems 3.2 firmware 1.2.11 60-2 trigger, wasted spark, modified SD1 inlet to clear bonnet
- with Rotrex waiting to be drop in when Vems is running

Offline Seight-v8

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Re: mis-fire
« Reply #6 on: July 11, 2010, 05:38:12 am »
Søren,

If you PM your email address, i will send you my latest config file.

I am now running V1.1.78, but can send you some previous versions if you need it.

regards

scott
Engine:Rover V8 4600cc
Vems Firmware:V1.2.38, GPS, SDcard, LCD & Dual lambdas, Wasted spark, 36-1 trigger, Cam Sync & Bluetooth serial.

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

Offline MGV8

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Re: mis-fire
« Reply #7 on: July 11, 2010, 08:47:52 am »
Hi Scott

It is fine with V 1.1.78 config as I have just upgraded my Vems to V1.1.78 firmware.

My mail: sms_dyrgaard@mail.tele.dk

Nice car you got, it must be pretty fast!

Regards Søren
MGB Roadster 4.0 Rover V8 - Vems 3.2 firmware 1.2.11 60-2 trigger, wasted spark, modified SD1 inlet to clear bonnet
- with Rotrex waiting to be drop in when Vems is running

Offline Seight-v8

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Re: mis-fire
« Reply #8 on: July 11, 2010, 01:03:18 pm »
done,

you should have an email soon, let me know who you get on.

regards

scott
Engine:Rover V8 4600cc
Vems Firmware:V1.2.38, GPS, SDcard, LCD & Dual lambdas, Wasted spark, 36-1 trigger, Cam Sync & Bluetooth serial.

http://www.vems.hu/wiki/index.php?page=MembersPage%2FScottRichmond

Offline MGV8

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Re: mis-fire
« Reply #9 on: July 12, 2010, 03:19:03 pm »
Thanks for the config file.
I use it as starting point for tuning of ignition map, and when I install injection as basic setup for fuel. I’m waiting with installing injection to I have ignition running smooth and stable.

I still have problems with ignition seems as one of my coil packs are defect. Four of the cylinders 1-6 and 5-8 are not burning good – based on examine of plugs after a drive.

The car hesitates when given full throttle and some times misfires. Some times it feels as it pulls as it shut for a short time when accelerating.

Have you any experience with dwell settings? 

When test with timing light it seems as sometimes ignition are missing on cyl. 1 but cyl. 6 ok, and that’s the same common coil!

I have tried to connect LED´s on input to coil pack and seem as signal from Vems is ok

Must be a defect coil pack!
MGB Roadster 4.0 Rover V8 - Vems 3.2 firmware 1.2.11 60-2 trigger, wasted spark, modified SD1 inlet to clear bonnet
- with Rotrex waiting to be drop in when Vems is running

Offline MGV8

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Re: mis-fire
« Reply #10 on: July 17, 2010, 07:59:05 am »
Changed coil pack, and engine running perfect with wasted spark. :)
MGB Roadster 4.0 Rover V8 - Vems 3.2 firmware 1.2.11 60-2 trigger, wasted spark, modified SD1 inlet to clear bonnet
- with Rotrex waiting to be drop in when Vems is running