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Not starting, CAS, ME221

9K views 71 replies 10 participants last post by  MarkGolf 
#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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#35 ·
Cheers all, thanks for tuning in to try and help..

Ignition not left on, well, nothing out of the normal but certainly not between it's last drive and the failed start... New coils now anyway.

12v feed is spot on..

Lost syncs, that's blowing my mind a bit but during those tests, my battery booster was dying so cranking wasn't the best, if that makes a difference? I'm getting to the point of wanting to buy another CAS, just because but having 2, I imagine 1 is ok.

I have just been out again, tested voltage to coils, plugs and engine earths, all good.

Used a 12v LED on injector plugs, each illuminated it as bright as each other.
Performed test again but connected to the injectors, each clicked on and off fine.
Fuel pump runs and sounds healthy, can hear it flowing through the rail.

Spark, tested with new plug, spark looks weak but I'm now doubting if this is actually normal.

So now, I really am just at a dead end over something that should be bloody simple.

My plugs get wet, after removing and drying them, so I believe the injectors are firing fuel ok.
I am getting a spark
Fuel pump works (assuming it's running while cranking)
CAS shows life on MEITI, unplugging it, stops spark, plugging it back it, spark returns
New coil pack fitted now.
New spark plugs but not fitted.

I haven't pulled injectors to see them actually spraying during crank
I haven't done a compression test

If 1 of the 2 sensors in the CAS sensor was failing, would I still get spark?

I'm just clueless now
 
#39 · (Edited)
Hi Zed, May take you up on that.. yet to get around to a compression test but thinking that’s my next step.

taking note of points mentioned, I tried a base map and an earlier map, no change, so returned back to my proper map.
Checked everythinggggg in terms of timing, plugs, leads, coils, CAS plug, all as they should be. Crank timing mark lines up with cylinder 1 TDC.
A friend was squirting easy start fluid into the throttle body and it still wasnt firing but not sure how well that stuff works

so next is compression test, if that checks out (I’m fearing the worst which would be really strange if it is a compression issue) then want to check fuel pressure, maybe injectors spray a bit of fuel and then just flop. Will cross that bridge after the comp test, wish me luck!

off topic, want to get a permanently fitted fuel pressure gauge, anyone done this while keeping the original FPR?

Cheers
 
#40 ·
Sytec do a test gauge. Ive used it in past. Inline fuel hose adaptor and tees off with a nylon capilairy hose that comes with about a metre so you can run into cabin and see pressure... its only for test purposes mind. Worked a treat.

You got a good ground on ecu ? Or more importantly the ground pin used for triggering. Just summit else to check. Need the ecu pinout for your model to ensure right pin and good ground.

Sent from my SM-N950F using Tapatalk
 
#42 ·
Cheers!

As far as I know the ground is good, I believe the ECU earths to the engine, 2 wires going to the intake manifold.. Ground pin for triggering, would need to know where that is.

Cheers for the info on the gauge, I want something to test while trying to trouble shoot this problem but while researching, I found a company called Radium who make a fuel rail which can have a gauge stuck to one end of it, I like that and happy to keep the gauge in the bay. A lot of money just for a gauge but not really any other options which are as neat.

I'll get round to a compression test this weekend.
 
#43 ·
I want something to test while trying to trouble shoot this problem but while researching, I found a company called Radium who make a fuel rail which can have a gauge stuck to one end of it, I like that and happy to keep the gauge in the bay. A lot of money just for a gauge but not really any other options which are as neat.

or you can get different regulators and fit a gauge to them



Rich.
 
#44 ·
Cheers again guys!
Willl look into the permanent gauge.

Compression test earlier, I have compression, all plugs removed, WOT, turned over for 5 sec

slightly varied readings from a stone cold turn over, battery starting to give up
Cylinder 1 - 4

216
183
161
209

not great on 2 and 3

unsure of where to go next here, is 2 and 3 my issue or can I move on to the fuel system?
 
#45 ·
The difference is a worry but none is low enough to prevent running. I recall the minimum spec of 125psi (for the original 1.6) but I can't remember the maximum difference allowed between cylinders. (Pretty sure your 216 and 161 psi results are a fair way outside it though.)
 
#46 ·
I would still expect it to start, surprised by the compression numbers but I’m hoping that is down to not being run for a month and tappets in need of pressurising again (it’s always tappety after sitting for a few days) and oil coverage to cylinders etc. I’ll worry about that another time, has been running perfectly up till this.
 
#47 ·
New pressure testing kit on order.. so I will plumb that in on the input line to the rail and test pressure while cranking and on key priming.

like the look of these radium fuel rails, they have a bolt on gauge too.


If my fuel pressure is ok, what next?! Pull cam cover and check timing up there?
fuel injector flow test?
 
#48 · (Edited)
This probably isnt it, but as you said the spark looks weak, possibility a failing ignitor. - but im guessing the ignitor is part of the coil packs in a mk1?, and you have replaced them.. And if the ignitor failed you would get no spark at all..
If you are getting fuel, and spark, it must be a timing issue?
If you have checked mechanical timing? Both crank and valves, then it must be ignition timing? - have you checked ignition with a timing light?

I would guess at either cam sensor, crank sensor or ignition timing..

Just trying to be logical lol..
 
#52 ·
Cheers again guys, however, got an update..

New NGK 7's plugs, I gapped them to .610 and fitted them over the weekend and that was that, didn't even attempt to turn it over.

Today, my fuel pressure test kit arrived, went out and plumbed it in, turned key and gauge went straight to 40psi.

Cranked over to see pressure during cranking and the thing fired up!! Total surprise and turned it off!
Quickly checked for any leaks in the test kit and went back for another crank and again, fired up and run perfectly, see vid's below. Tappety as expected but idling smooth and running on all 4, happy but confused, the only change has been the plugs between not working and now.

Removed pressure kit and all back to normal, fired up and now it's sounding like a Subaru, misfiring. Great!





Checked for leaks on fuel pipes, pushed in and wiggled all the HT leads, fiddled with wires, no change but then I noticed a mess around the exhaust manifold, WTF!!, switched off. Had a poke around, confused, worried... Logic is just telling me, misfiring on a cylinder so fuel is being blown through and that's what I'm seeing, obviously a shit gasket, not the first!





So, car is running but misfiring, it was running fine to start but it clearly developed, is an injector at fault and washing an injector out, dodgy leads, plugs.. Not sure yet

1 thing which is strange, this is with the previous coilpack and the new, on the metal bracket, 2 and 3 are etched into it, my car is running the plugs opposite to these, 2 etched mark goes to 3 and vice versa. Been like this for years and now across both coilpacks. I did switch the leads and the car still started but ran marginally rougher, longer to start. Switched back.

What now?! Send injectors for testing? I do hear them click when testing but now im worried one could be leaking..

Vids coming...
 
#54 ·
Very strange[emoji848][emoji848][emoji15].
So injector either stuck open or commanded open by ecu?
Do mtech do a ecu test? In the post or summit.

If the injector is permenantly stuck open then just applying voltage to the fuel pump would see which 1.
Im leaning towards ecu fault...youve been through everything else.

Sent from my SM-N950F using Tapatalk
 
#55 ·
I'm really hoping it's not the ECU, I will go crazy if so, a screwup with that before caused me to lose an engine.

I don't think it is however, I think my issue is an injector at the moment.

I plan to nip out and start the car and see if it misfires, if so, I'll shut it off, remove plugs, check if one is obviously wet, if not, I'll trigger to fuel pump to run and try and see if any are spraying. I do have control of each injector and during my tests, I could hear each one clicking, so I assumed they are opening and closing fine but perhaps not.

I do have some 501 bulb holders, I'm half tempted to wire each injector with a bulb and watch what happens during idle..
 
#56 ·
I'm really hoping it's not the ECU, I will go crazy if so, a screwup with that before caused me to lose an engine.

I don't think it is however, I think my issue is an injector at the moment.

I plan to nip out and start the car and see if it misfires, if so, I'll shut it off, remove plugs, check if one is obviously wet, if not, I'll trigger to fuel pump to run and try and see if any are spraying. I do have control of each injector and during my tests, I could hear each one clicking, so I assumed they are opening and closing fine but perhaps not.

I do have some 501 bulb holders, I'm half tempted to wire each injector with a bulb and watch what happens during idle..
I thought id better just mention, that when i was deciding what ecu to go for (either me221 or ms3mini), i called up my local tuners and spoke to them about what one they prefer to tune or have the most experience with. One of the things that they mentioned (im going back about a year now) was that the me221's were giving them problems with a strange intermmittant misfire. Unfortunately i dont have any more details than that, other than i think it was something to do with the current firmware, so they thought. Maybe worth checking you have the latest firmware version? That was enough to sway me towards the ms3 mini.. They guys are hybrid tune in suffolk, they have a good reputation.. Just a thought...
 
#57 ·
Good luck. I think youll find the 501 will just glow due to the high frequency of firing.
Should be able to test fire each injector in the meite software?
Seemed like a big leak of fuel too so have hosepipe primed and ready.
Id be inclined to run fuel pump first to check all shut. And if memory correct then fuel inj should be set to inverted in settings. Fingers crossed.

Sent from my SM-N950F using Tapatalk
 
#60 ·
Good luck. I think youll find the 501 will just glow due to the high frequency of firing.
Should be able to test fire each injector in the meite software?
Seemed like a big leak of fuel too so have hosepipe primed and ready.
Id be inclined to run fuel pump first to check all shut. And if memory correct then fuel inj should be set to inverted in settings. Fingers crossed.

Sent from my SM-N950F using Tapatalk
Good point on the bulb and trying fuel pump first, I’ve got some LED’s so I’ll give one a try to see what happens.

cheers
 
#58 ·
I’ve done around 8-10k miles or so over 4 years with this entire setup so I’d hope it’s all solid really, I purposely avoid doing firmware updates to the ECU as that’s what killed my last engine.
ECU had a fault and was exchanged for another but with newer firmware, what I wasn’t told was that the timing table was now additive, so my timing was advancing itself as the revs went up. That led to detonation and kaboom for me. That’s in the past now and took it on the chin.
Unless my ECU has developed a fault over the 2 days it was parked on my drive, I’m trying to avoid pointing the finger at that until I check the injectors over, my gut is with those being the issue atm. The car has literally run perfectly up till now.
 
#61 ·
Back on the car, gave it a quick turnover and it fired up instantly, so i shut it off and pulled the plugs, noticed plug 1 was clean and wet and looking in to the top of the piston, there appeared to be fuel on top... Anyway, double checked the plug worked, it did, ran FUEL pump but couldn't see leaks or the puddle growing, activated the injector at 1 second pulses but again, couldn't see the mist or anything, tried on another and same, so it must just spray into a spot which cant be seen when looking down.





So that's where I am, guessing the injector on cylinder 1 has an issue.

So I think my next move is to remove them all and send off to Injector Tune for a test and clean up...

Did a compression test again now it has been run as the low readings were bothering me..

218
212
207
211

So that's good, not sure why the previous readings were low but I'll take these.

Oh, and thanks to the leak, I noticed a crack in my downpipe. Never rains and all that....



Should be able to get a quick weld patch while in place so not a huge issue.


Beginning to lose patience with the car now. This is on top of the need to swap the gearbox. ffs
 
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