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@Markbcars
Eunos Turbo
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Discussion Starter · #1 · (Edited)
Evening!

I last drove my caron Friday, absolutely fine..

Started it again today and it spluttered into life and was clearly misfiring and popped.. turned it off and tried to restart but no joy, just a struggling to catch turn over. Poked around, everything appeared fine in terms of connectors to coilpack and CAS. Unplugged CAS and it seemed to turn over more freely, plugged it back and the car continued the same. So I think the CAS has died, that’s fine, I’ve got an old spare to try.
I just want to check, does the me221 ignore the positioning of the CAS or will I need to position it again and check with a timing gun?
It’s been a while since I’ve been in to all of this and for some reason, I’m under the impression that the position of the CAS is ignored due to my me221.
Is there anything I can check on meite that would confirm this as the problem?
Also, can you buy upgrades or just stick to an OEM new one? I really Cba with second gamble on this kind of critical part.

cheers
 

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layabout
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I just want to check, does the me221 ignore the positioning of the CAS or will I need to position it again and check with a timing gun?
my take....

the ecu gets it's timing reference from the cas.
the ecu is told (programmed?) where TDC is (or a similar rotational position) then supplies ignition & fuel timing advance / retard based around that reference...

if you move or replace the cas the reference is 'lost' relavant to the ecu's programing :unsure:


Also, can you buy upgrades or just stick to an OEM new one? I really Cba with second gamble on this kind of critical part.
you can convert to an external crakshaft sensor, this is used on mk2 mx5's with a cam-pulley sensor so oem ish option - you can run just the single sensor if you don't run or want sequential injectiono_O

theres several possible trigger-wheels available including a genuine Mazda 36/2 pattern.





Rich.
 

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VVT swapped NA & TD04 turbo NB
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the ecu gets it's timing reference from the cas.
the ecu is told (programmed?) where TDC is (or a similar rotational position) then supplies ignition & fuel timing advance / retard based around that reference...
yes, literally on MEITE, you input the trigger offset in degrees, here's mine, I don't see how replacing a crank sensor would affect the base timing of the engine, what am I missing?

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Happily expanding the To Do list since 1997
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Replacing a crank sensor wouldn't affect timing but Mark's talking about replacing a CAS which has wide adjustment and half a degree of CAS rotation is a degree of crank rotation. So that really needs a timing light to reset it.
 

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Replacing a crank sensor wouldn't affect timing but Mark's talking about replacing a CAS which has wide adjustment and half a degree of CAS rotation is a degree of crank rotation. So that really needs a timing light to reset it.
Apologies I dont know why I instantly thought of the crank sensor. I also assumed OP had a mk2 for some reason where the CAS is fixed and not adjustable like on the mk1, oops :)
 

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@Markbcars
Eunos Turbo
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857 Posts
Discussion Starter · #6 · (Edited)
Cheers Guys! Great info Zed! I would love to do that swap, I do run a mk2 block and gearbox so could get away with the fitting of the starter and I have the toothed wheel so I'll look into that.

For the time being. the issue is that I can't remember if Skuzzle would have adjusted the position of my CAS when the car was mapped. I know that I had set it to 10 degrees once I got it running again before taking it down there but I don't know if it was then changed before mapping. i'm pretty sure it wasn't changed but I can't be certain.

I have just had a brain wave, would like some advice on this. in MEITI, I have the "fixed fire 10 degree" check box. Would I be right in thinking, I should enable that, set my CAS up, confirm that it is at 10 degree's and then turn car off, disable the fixed fire and everything should be good?

When I check the "mapping" section, I see the "ignition table" and that has a started value of 16.5 with a gradual climb to 39.. so I should see timing at idle go to 16.5 if I have read that right?

Cheers
 

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Happily expanding the To Do list since 1997
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Yes, that fixed fire setting should work just as you described. (Not that I'm familiar with MEITI, but TunerStudio has a similar fixed timing setting for the same function.)
 

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16.5 degrees seems a tad too far advanced for idle.
Prior to supercharging mine I did the 14 degree mod, but once modified and with MS2 Ecu my idle ran smoothly at 10 degrees advance.
 

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I've done this recently and i farted about with things for ages to find out my crank pulley had slipped and the timing was way off.

Once I'd diagnosed that and replaced the part I found that by far the best way of setting the base timing was turning on fixed fire in meite then adjusting to 10 BTDC using the trigger offset. I only needed to adjust by 4 degrees to get it bang on.

You need to cycle the ignition after changing the value of the offset.

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@Markbcars
Eunos Turbo
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Discussion Starter · #10 ·
Cheers guys!

I've just been out and swapped the CAS to a spare I had but issue persists. It could be that the spare, which has been in a bag in my boot for a number of years is dead, I know it was fine before going in my boot. But same thing, car just turns over, can smell fuel but no sign of trying to catch now.

Will test for a spark, I assume I wont have spark but will test to be sure. I can small fuel from the exhaust. I'll take a stab at my spare CAS being dead. I really don't want to buy a second hand one but also don't fancy the £350 for a new one, rock and hard place.

Any other tests I can do?

Cheers
 

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VVT swapped NA & TD04 turbo NB
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Cheers guys!

I've just been out and swapped the CAS to a spare I had but issue persists. It could be that the spare, which has been in a bag in my boot for a number of years is dead, I know it was fine before going in my boot. But same thing, car just turns over, can smell fuel but no sign of trying to catch now.

Will test for a spark, I assume I wont have spark but will test to be sure. I can small fuel from the exhaust. I'll take a stab at my spare CAS being dead. I really don't want to buy a second hand one but also don't fancy the £350 for a new one, rock and hard place.

Any other tests I can do?

Cheers
Might be worth trying the car in diagnostic mode for what it's worth.
 

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@Markbcars
Eunos Turbo
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857 Posts
Discussion Starter · #12 ·
I did see that the latest version of MEITI has a diagnostic panel, I plugged it into the car but if I'm honest, didn't spot anything that would help me, I'll try again and do a screenshot. No idea what it is telling me.
 

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Happily expanding the To Do list since 1997
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No, that diagnostic mode is built into the stock ECU so won't do anything after a swap. I don't know ME221 but there is probably some means of logging whether or not it's getting timing pulses from the CAS.
 

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Dead coil pack?

When mine went it spluttered first then died. If it’s fuelling ok then that suggests to me your CAS is OK but something’s bad on the ign side (or idle air control valve I suppose, but less likely)


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No, that diagnostic mode is built into the stock ECU so won't do anything after a swap. I don't know ME221 but there is probably some means of logging whether or not it's getting timing pulses from the CAS.
Literally a logging mode on MEITE, thanks for the info, I always thought the diag box worked to bypass the ECU to force 10BTDC, I'll update my mental notes :D


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@Markbcars
Eunos Turbo
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Discussion Starter · #17 ·
Coilpack was my very first thought but as they are 2 separate units, I figured that the car would still try to run on 1 of them?

I am yet to get back on the car but I will check for spark. Would be nice if it was the coilpack as I don't think I have replaced those.


Ahh so on that Diag view, I should see some activity there against crank/cas and if so, means my cas is ok.. I will give that a go later
 

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Hiding from the Ayatollah or making Full Metal Jac
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Just want to confirm your fuel pump is actually running ? does it hum ?
 
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