Author Topic: So Found the problem whats the soloution  (Read 12745 times)

Offline Agriv8

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So Found the problem whats the soloution
« on: April 11, 2007, 09:45:36 pm »
using my mates decent sealy gun ( can be added to the list of those that work )

Running the car on the Dizzie get the TDC spot on ( with No advance - will update that post that shortly ) Trigger toothe needs to be tooth 8 after the gap.

Then suddenly notice bu66er gone back to fireing on 3 coil packs ( So after just about managing to keep my composure thinking that  I have blown ign driver connected to pin 36 Again )

Anyway as a last ditch atempt thought hang on it was working fine on Monday ( firing all 4 ) so retraced my steps

Setting Trigger tooth to anthing less than or = 7 ok all 4 work - 8 and above we loose sparks.  >:( >:( >:(. so what causing that then. ???????????

Off back to see if it is always the top one of the Ign sequence list ( suspect it is ).

So suspect that I hadnt really blown the ign driver in the first place !!!!

REagrds and Confused

Agriv8



'The older I get the faster I was'

Offline rob@vems.co.uk

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Re: So Found the problem whats the soloution
« Reply #1 on: April 11, 2007, 09:59:45 pm »
What is your TDC after trigger value?

Offline Agriv8

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Re: So Found the problem whats the soloution
« Reply #2 on: April 11, 2007, 10:31:43 pm »
Hi rob 80,

Jus confirmed it doent matter where 36 is in the ign order it wont fire.

it must be somthing to do with it being the last in the list

ie pickie



regards

Agriv8
'The older I get the faster I was'

Offline Agriv8

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Re: So Found the problem whats the soloution
« Reply #3 on: April 12, 2007, 08:10:26 am »
Trying to think of a solution to this.

Could rotate my trigger a tooth or 2  at the moment it is centered using the crank pulley and held in place with the 3 bolts that hold the belt pulley. ( so can only rotate 120 or  240 deg ) to redrill the trigger would mean removing the crank pulley.

Unfortunately its not an easy task taking the crank pulley of in my car ( radiator and oil cooler off ) and a pair of inboard shocks then need to loosen the engine mounts to get the pulley off.

But suppose if it my only option.

Regards

Agriv8
 

'The older I get the faster I was'

Offline dnb

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Re: So Found the problem whats the soloution
« Reply #4 on: April 12, 2007, 09:59:20 am »
Sounds like you're running in to having a problem with trying to do a spark event over the time when the ECU is resetting for the next cycle.

You don't talk of the "TDC before the trigger" parameter (measured in degrees).  You should use this to set the timing, not moving the actual trigger tooth around.

Set your trigger tooth to say 5, then move the "TDC before the trigger" to get the timing correct.  On a v8, you should aim to get "TDC before the trigger" to be around 60 degrees +/- 10 degrees (this is in case of a misfire & kickback while starting)

Offline Agriv8

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Re: So Found the problem whats the soloution
« Reply #5 on: April 12, 2007, 10:22:07 am »
MMmmmmm Intresting that would make sense.

So where is TDC before the trigger set ? cant see it on  'Primary trigger settings' got an after parameter.



(  old trigger settings from a previous screen dump )

Regards

Agriv8
'The older I get the faster I was'

Offline rob@vems.co.uk

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Re: So Found the problem whats the soloution
« Reply #6 on: April 12, 2007, 11:02:42 am »
Doh! I meant After

If the trigger is 90 deg BTDC your trigger would be best to be 60deg BTDC.
So you want your trigger tooth to be 3
and TDC after the trigger to be 60
Set your cranking advance to 10deg BTDC and time your engine in trimming the TDC after the trigger value accordingly so that the crank pulley shows 10deg at cranking.

Have a battery on stand by and watch the starter motor temperature - you may want to pull your plugs to lessen the load on things.

Offline Agriv8

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Re: So Found the problem whats the soloution
« Reply #7 on: April 12, 2007, 12:11:59 pm »
So when I get chance tonight I am leaving the trigger wheel in its current location.

and setting my trigger to 3 and my tdc after the trigger to be 60.

It doesnt make sense to me sat in the office It may when I am looking at the engine.

regards


Agriv8
'The older I get the faster I was'

Offline rob@vems.co.uk

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Re: So Found the problem whats the soloution
« Reply #8 on: April 12, 2007, 01:56:52 pm »
Let me try and explain a little better.
The missing tooth occurs at 90degBTDC so if you set you trigger tooth to be 0 then you'd need your TDC after the trigger set to 90deg.
You have a (notional) 36 tooth wheel, so each tooth = 10 deg of crank rotation.
A good trigger position is around 60deg BTDC so setting trigger tooth to be 3 means that VEMS will consider the 3rd tooth after the missing one to be the trigger tooth 3 teeth = 30deg.

The next tooth setting of 9 means that VEMS counts the next 9 teeth (12 teeth after the missing tooth) which is of course 90deg of crank rotation.

Offline Agriv8

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Re: So Found the problem whats the soloution
« Reply #9 on: April 12, 2007, 10:13:21 pm »
 ;D ;D ;D  Yippeeeeeeee    ;D ;D ;D.

Had it running tonight from the coil packs !!!!!

BIG Thank's for all of you that have taken time to get it into my thick scull.

So wiring tidy and bolting eveyting back together.

So a double check of the Lambda calibration and onto a bit of tunning.


Regards

Agriv8

'The older I get the faster I was'

Offline Tony C

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Re: So Found the problem whats the soloution
« Reply #10 on: April 14, 2007, 09:49:13 pm »
im watching this with interest ready for doing mine :)

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Offline r2d2hp

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Re: So Found the problem whats the soloution
« Reply #11 on: May 14, 2007, 05:19:09 pm »
Does this mean you can only select the timing in 10 degree steps or is that taken care of in the mapping tables somehow.

Offline rob@vems.co.uk

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Re: So Found the problem whats the soloution
« Reply #12 on: May 14, 2007, 06:13:38 pm »
Its a 36 tooth trigger, each trigger is 10deg apart.

You use this for the reference point to trigger the ignition, from this point ignition is offset in 0.25deg steps.

Rob