I would appreciate some help with a couple of ignition/spark problems I have with MS and ford Coil pack, running wasted spark on ITBs.

Main problem - engine idles, but has slight missfire.
When using timing light on cyl 1 and 3 the timing fluctuates and seems weak. On cyl 2 and 4 however, these are steady with strong spark. As the pair of leads share the same driver, I can not understand why there is this difference. I have tried a different coil pack, but it made no difference.

I'm a bit lost on this one, any suggestions?

Second concern, which I have overcome (could possibly be related).
Having set up the 36-1 trigger wheel, timing in correct place, sensor on tooth 9. Entered 80 degree in Tunerstudio and timing 8 degree BTDC. However, timing light showed 4 degree After TDC!
I had to reduce the 80 degree setting by 12 (to 68) to get the light showing 8 BTDC. Check everything (how many time can you count 9 teeth!) and all seems to be is it should.

Making the 12 degree change worked, so have not worried too much (maybe I just can't see what I have done wrong). Only problem seems to be the above missfire.

Any advice, or just keep my head in the sand

Thank

Danny

[Edited on 21/7/13 by DannyC]

Are you sure the timing marks on the engine are accurate? Have you put No 1 at TDC and then checked the marker?

if you swap one and four on the top of the coil pack, does the problem remain on 1&3 or change to 3&4 ?

quote:

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Originally posted by DannyC
I would appreciate some help with a couple of ignition/spark problems I have with MS and ford Coil pack, running wasted spark on ITBs.

Main problem - engine idles, but has slight missfire.
When using timing light on cyl 1 and 3 the timing fluctuates and seems weak. On cyl 2 and 4 however, these are steady with strong spark. As the pair of leads share the same driver, I can not understand why there is this difference. I have tried a different coil pack, but it made no difference.

I'm a bit lost on this one, any suggestions?

---

quote:

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Originally posted by DannyC
Second concern, which I have overcome (could possibly be related).
Having set up the 36-1 trigger wheel, timing in correct place, sensor on tooth 9. Entered 80 degree in Tunerstudio and timing 8 degree BTDC. However, timing light showed 4 degree After TDC!
I had to reduce the 80 degree setting by 12 (to 68) to get the light showing 8 BTDC. Check everything (how many time can you count 9 teeth!) and all seems to be is it should.

Making the 12 degree change worked, so have not worried too much (maybe I just can't see what I have done wrong). Only problem seems to be the above missfire.

Any advice, or just keep my head in the sand

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Scudderfish - Yes, quite sure timing marks are correct. I am concerned that I might have changed a setting in Tunerstudio.

Gremlin - I haven't tried that, I shall give it a go and see what effect it has.

MikeRJ - It's one of the fancy ones, albeit cheap. It does have an arrow on it, so I'll try it the other way around on 1&4 to see if it gets any better. Although as the engine is missing, it would suggest there is a problem rather than just the light not picking up the signal very well.

Thanks for the replies so far chaps.


Danny

[Edited on 21/7/13 by DannyC]

Hi Danny,

Can we offer our services?

We can sort your spark problem (what ever it is) and map on our in house rolling road for £250

Its a long drive but worth it! - we have mapped cars for loads of folks on the forum ;-)

Dale

www.baileyperformanace.co.uk

Are you using 2 BIP373's to fire the coils directly? make sure that you have your spark settings "Going high" and "Inverted"

Is your timing light adjustable or fixed?

If you go to datalogging and do a datalog of your engine running and your missfires, feel free to email it to me along with your .MSQ file. While watching your laptop you aren't getting the RPM drop to 0 at any point are you? this would indicate a loss of sync between your engine and megasquirt which would give you a missfire.

Dave_424@hotmail.co.uk

Thanks for the offer Dale, I may well get it mapped, but would like to sort out the problems myself first (with a bit of help from the forum of course)

I changed the leads over on the coil and the timing light effect changed as well. This would suggest it is the type of light. I used an ordinary one and it seemed OK on either lead.

The trigger wheel setup problem was my error, (no surprises there then). I forgot what the correct No. of degrees each of the crankshaft timing marks equated too.

Dave_424 - What are BIP373s? I am using a ford coil pack.
I have recorded a few data logs, but still trying to understand them myself at the moment. I shall send one over when I know I have recorded the right data.
I have had tunerstudio 'freeze' a couple of times, whilst the engine was running. I assumed this was a lost signal or it didn't like the changed I had made.

Thanks

Danny

BIP373's are your ignition drivers, you will have two of these, one for each side of the coilpack. That is if you aren't using an EDIS module.

One word of warning, don't adjust any ignition settings while the engine is running. I stupidly did this and burned through an insulator on one of my ignition drivers, replaced the ignition driver with a new insulator and all is good, but I won't be doing that again.

Dave

I know this has been mentioned, but the timing issue is an artefact of wasted spark and a "clever" timing light.

Basically the timing light counts the spark rate to estimate the RPM, and then uses that RPM to set the timing to the value that you have selected.
But, with wasted spark the timing light estimates the RPM inaccurately by a factor of 2, which means that when you ask for 10deg you get only half of that (i.e. 5deg).



It might be worth running a trigger log, these can sometimes be quite revealing.

To simplify things I have used an ignition timing of 0 deg, then turn the advance on the timing light to 0, negates any errors like others have said.

Dave

quote:

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Originally posted by DannyC
Thanks for the offer Dale, I may well get it mapped, but would like to sort out the problems myself first (with a bit of help from the forum of course)

I changed the leads over on the coil and the timing light effect changed as well. This would suggest it is the type of light. I used an ordinary one and it seemed OK on either lead.

The trigger wheel setup problem was my error, (no surprises there then). I forgot what the correct No. of degrees each of the crankshaft timing marks equated too.

Dave_424 - What are BIP373s? I am using a ford coil pack.
I have recorded a few data logs, but still trying to understand them myself at the moment. I shall send one over when I know I have recorded the right data.
I have had tunerstudio 'freeze' a couple of times, whilst the engine was running. I assumed this was a lost signal or it didn't like the changed I had made.

Thanks

Danny

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I'm using a USB converter (from Maplin). I am glad to know wasn't something I was doing wrong!

I shall give the lamp test ago tonight, just to make sure nothing else is wrong.

Thanks

Danny

Well, lamp test went OK, so no problem there.

I now need now is to understand the datalog output. Is there a list of the acronyms used, as many do not seem very obvious to me.

Danny

quote:

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I now need now is to understand the datalog output. Is there a list of the acronyms used, as many do not seem very obvious to me.

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Checked the leads and plugs?