Megasquirt Extra Users - Starting Issues

[Woznaldo]

I'm having issues starting my C1J on MS1Extra. I'm using an EDIS4 setup with wasted spark but not sure if my starting settings are right? (not the general setup, but things that need to be changed to start the car)

I have 440cc/min injectors (new Bosch Green Giants 0280 155 968)
Cranking Advance Angle set to 5 deg BTDC
Cranking PW at 1.4 ms for coolant temp of 28 deg C
After Start Enrichment is set at 10 % (which I think is +10% off the main fuel table. i.e. if the table is set at 50, +10% will give 55)

What setup of MS are people using and what Cranking Advance Angle do you use to get the car started?

Help appreciated.

Regards,

Woz

[Matty]

I think I had mine set to about 20 degrees (5 years since I last adjusted map).

Just advance it, and if it starts kicking back take a few degrees off the timing.

What its doing? Not firing at all?

On the starting enrichments table, I would start richer then back it off once you have it running.

Maybe try 20% from 0 degree then reduce it down the table from there.

Have you checked you are getting a spark and fuel? Is the cranking speed too high?

[Woznaldo]

Thanks Marty, I'll take a look.

It stutters like it's trying to fire, but never quite gets there. I've set cranking RPM to 500, but the engine cranks at 250.

Sometimes the Cranking Advance Angle drops off from wherever it's set to zero? I think this is the main issue.

[Matty]

How far away is the sensor from the pulley?

Sounds like not enough fuel if it's starts to fire then stops.

From memory the cranking figure sets the parameter where cranking ends, so if you have it set to 500 the cranking adv, fuelling etc.. Will all be cranking settings until 500rpm after that it runs on the main map.

Maybe enrich the Fueling around idle on the main map, as it may be going onto the main map and then underfuelling?

[Woznaldo]

Good point Matty. I'll crank up the required fuel. The After Start Enrichment is based off the main fuel map too so I'll tweak the Req Fuel and go from there.

Woz

[Matty]

To be honest you are better off leaving the require fuel to the correct number, but adjust the individual boxes on the Fueling map. If you change it too far from where it should be, you may find the top/bottom end of the map you run out of adjustment as the scaling is wrong on the required fuel.

If you can run closed loop and have a target lambda map, then it should fuel itself and tell what what the correction factor it is for that particular cell in the grid.

[Woznaldo]

I think the required fuel change is just quicker to do the adjustment, but then you'd need to adjust back down and rescale the VE table anyway.

[Matty]

Yeah it's quicker for an overall change, what I found with mine, was that I had to adjust a boxes in step numbers no smaller than 5 at a time,otherwise the adjustment was so fine it didn't do anything, and I ended up at the top end of map going beyond the highest number you can input in the box. so I had to change the required fuel, and remap.

The calculator for the required fuel gets its very close to where it need to be. 👍

[Woznaldo]

Thanks Matty. I found some time today to do a couple of checks, the first being a physical check that all the injectors are firing. I pulled the fuel rail off and secured the injectors to the fuel rail with zip ties. I then positioned a few containers under each injector and cranked the engine. Turns out that only one batch is firing! 1 and 4 are good, but 2 and 3 are not playing the game. As it's batch fire, I connected all four injectors to the INJ1 channel and retested. Sure enough they all fired! I changed the settings from '2 squirts alternating' to '2 squirts simultaneous' and the engine almost fired up!

I made a few adjustments to the Cranking PW but it didn't change much. Started to up the after start enrichment and that appeared to help a bit. Had to call it quirts after a few attempts, but will have another crack tomorrow.

[Matty]

Sounds like you are getting somewhere now then!

I found the easiest way, was to set all the ignition timing to a fixed setting...say 20 degrees, so when you get it running it's not advancing and retarding all the time, it makes it easier to get the idea fueling somewhere near right. If you also add say 10 degree of advance on the base row of the spark map, if it decides to cut out, the extra advance can help kick it going again before it totally cuts out. Gives you a bit more time to type the number in the boxes.

[Woznaldo]

I think I got similar advice when I first ran the car on MS using ignition only. I give that a go too.

I think I've still got some kind of spark issue? I'm going to reconfirm all the basics and go from there.

[Matty]

What colour is the spark? Should be bright blue.

Also are you running resistive plugs?

[Woznaldo]

What colour is the spark? Should be bright blue.

Also are you running resistive plugs?

I haven't checked spark colour yet, but the car did run on ignition only for over a year? Regardless, I will still check to confirm all is well. Yes, i'm running NGK BR9IEX plugs.

When cranking the car yesterday it would almost catch a couple of times then let out an almighty backfire! That's a pair of pants I won't be using again!

[Matty]

Sounds like it is too lean. It's taking a couple of cycles to get enough fuel to ignite, at which point it's firing on the cylinder that's on its exhaust stroke. The fun and games of wasted spark hey!

Had a few fires in my time on the engine dyno, using wasted spark and vintage solex carbs.

[Woznaldo]

Still having dramas with starting so I pulled the ECU of the car to run it on the Stim (engine simulator). I'm not sure if these symptoms are the same as when connected to the car, but it looks like PW at a certain RPM drops to zero when either the CLT or MAT goes above an associated temp? I.e. If I set 250 rpm, the PW drops off at 23 deg C. If I set 5000rpm, the PW drops off at 40 deg C???

I've checked the settings and nothing looks out of place?

I've tried to reload the firmware and that hasn't helped either?

Maybe my Stim isn't at it's best??

[Matty]

Sounds a bit odd?

Have you tried to do a data log when it runs?

Is it still showing an RPM on the laptop screen when it cuts out, or does that dial go pink as if it's not running?

[Woznaldo]

Sounds a bit odd?

Have you tried to do a data log when it runs?

Is it still showing an RPM on the laptop screen when it cuts out, or does that dial go pink as if it's not running?

I did a datalog while on the Stim and rpm is fine. Doesn't drop out at all?

Datalog was uploaded to the MS1EXTRA forum and I'm awaiting a response.

[Woznaldo]

I thought I'd close this out so if others had the same problem they could get it sorted too! Firstly it was my poor understanding of how the settings in MegaSquirt work, but I'll go through it anyway.

To get the car started MS uses an independent Cranking PW Table which is based purely on the engine temp (CLT) and switchover threshold which is roughly 100 rpm above the rpm that your engine turns over. Example:

My C1J cranks at 200-250 rpm so I have set my threshold at 400 rpm. If the engine fires the rpm climbs above the threshsold (>400 rpm) and the ECU switches over to the main Fuel Table.

There is also an After Start Enrichment (ASE) table based again on CLT and is a percentage added to the main Fuel Table for a short period of time after initial start. The duration can be set by ignition events of time and can be constant until events/time expire or decay until events/time expire. Example:

At a starting temp of 10 deg C, my ASE says 110%. This means 100% of the main Fuel Table + 10% extra = 110%. The duration is 100 ignition events in decay mode.

(this is one of the things I messed up as initially I just put 10%. This actually means cut 90% of the fuel off!)

There is another thing that MS can do, and that is assist with the warmup of the engine until it gets to a sensible level (around 70 deg C) This is very similar to ASE, but it's duration is only determined by CLT. i.e. it will keep adding until the CLT is above 70 deg C.

This was one of my main issues. (I didn't want to touch warmup until I got the engine started, but the default was set at 0. When in reality zero extra is actually 100% (of the main Fuel Table). So it is now at 100% for every temp in the range).

Finally, as per ASE and the Warmup Wizard, there is a function called 'Coolant Related Air Density'. This was the part the I really didn't click with as the MS manual tells you to steer clear of it until everything else is sorted AND you have a very good grasp of EFI tuning. It is a fuel correction based off CLT and MAT (or IAT) and tweaks the main fuel table based on those inputs for part or all of the rev range. As per ASE it uses total percentage to input the amount you want to add. i.e. add 10% = 100% main Fuel Table + 10% additional = 110%.

Hopefully some may find this useful as nobody on the MS forums picked this up. (maybe because it was a very basic error?)

Now I might be able to start tuning the damn thing!

[Trevhib]

Finally Woz, you cracked it, well done mate

[Matty]

Glad you got it sorted. I think most people start with a base map, then work off that, so it already has the default values in the boxes. In all honesty I have never adjusted mine. I guess you started from a blank map?

I'm going for a DTA ecu on my EFI build, some of the programming on the megasquirt software is very user friendly as you have probably found out.

[Woznaldo]

I've just upgraded my processor to run MS2. Gives better definition, larger fuel tables (more cells) and a lot more options. The changeover wasn't too bad either. I'm still running EDIS wasted spark for the short term, but plan to run the same coil pack and get MS2 to control everything (not the EDIS module).

The software setup is a little different to what I mentioned above as the cranking table is a percentage of the main fuel table, and the in some areas 5% extra is 5% not 105% like above.

I'm having other (non-MS) related issues at the moment, but will get there in the end...

[Matty]

Woz how is yours running now? Did you get everyth sorted?

Any chance you have an MSQ file you are willing to share, or even a screen shot of the fuelling table and required fuel settings?

I'm hoping to get mine fired up in the next couple of weeks, and it would be good to have a decent starting point!

I'm planning on using the standard AEI advance curve for now just to get it running, so fueling is the main one to sort out. I'm running the same injectors but fired sequentially.

[Woznaldo]

Matty,

I haven't touched the car since my last post in this thread, but gave it a shot yesterday after changing the starter motor.

I was getting nothing! The engine would crank at around 250 rpm, but not even a sniff of catching? I dropped the fuel, but still nothing. Even tried spraying some carb cleaner down. Still nothing. I pulled the plugs and they were pretty wet/oiled up, so I got my mini blow torch out and gave them a good clean.

This time when cranking the engine was catching, and then finally semi-caught. It idled for for around 40 secs before finally just dying.

Something that a mate noticed that the vacuum during cranking was only -10 kPa or -1.45 psi. Does this sound a bit low for vacuum during cranking? Should I be getting -20 or -30 kPa?

I'm going to drain the tank and throw in some fresh fuel, just to remove that from the equation, but struggling to see what the issue might be?

[Matty]

Ah no problem thought I'd ask. I'm about to try and get my Gordini headed motor going (either tomorrow or a friday).

I'm also converting a C1J at the moment to EFI?

Cranking wise that might not be far off, on idle it should be around 40-60kpa though.

It sounds like its over fueling if the plugs are wet. I'd be tempted to knock 20% off all the fuel table values, then gradually increase until it fires. What do you have the required fuel set to at idle? It should be around stoich 14.7AFR.

[Matty]

What did you do for fuel relay signal on yours?

I've been searching through diagrams, and I'm still trying to figure out where the power comes from to energise the relay?

It looks like the AEI grey/white tacho wire gives it a signal but I'm guessing this would be a pulsed (5V?) signal instead of fixed 12v...could be completely wrong though!

[tubbyG]

[QUOTE=Matty;409459
It looks like the AEI grey/white tacho wire gives it a signal but I'm guessing this would be a pulsed (5V?) signal instead of fixed 12v...could be completely wrong though![/QUOTE]

This method works for me. For my mappable ignition install, I have intercepted the A/B sides of the coil with some diodes before connecting to the grey wire, this allows the rev counter and fuel pump to work as normal

[Matty]

Ah that's good. What diodes did you use?

[tubbyG]

Ah that's good. What diodes did you use?

I cant remember off the top of my head. I did have some images on my project thread but photobucket has blocked them.

I have spare diodes and the diagrams in the garage so will upload a copy over the weekend for you to have a look

[Matty]

Is this the same? If so will head over to Maplins on the weekend.

https://www.rtoc.org/boards/showthrea...ed+spark+tacho

[tubbyG]

Yeah that's the one

[Woznaldo]

I had a bit of a play this morning and yes I was massively over fueling! I’ve pulled 15% out of the main fuel map and dropped the percentage of cranking fuel and things are looking a bit more promising. I’ll clean up both fuel and ignition tables while the battery recharges and then go again tomorrow.

As for fuel pump, I’ve retained the std loom from pump to relay, but then jumpered the relay plug and run a new wire from the plug to a separate relay board that has the fuel pump safety circuit.

[Matty]

Well I didn't mamanged to get exactly the same components, the Zener Diodes were 15V which I think should be fine anyway. The resistors were 1k Ohm but only 0.6W I have no idea what current they flow?

[Ian S]

They flow hundreds of amps just before they eviscerate.

The wattage rating will be at 70°C or so.

So you use Ohms law to work out how near you are to the wattage rating.

V = I x R

V is voltage drop across the resistor.

Assuming it's 15V as the Zener will limit it to that.

15 V / 1000 Ohms = 0.015 A or 15 mA.

Wattage = I x V

0.015 A x 15 V = 0.225 Watts.

14.5 Volts is likely to be the maximum from the alternator isn't it?

So there'd never be anything Zenering the Zener. How does the tacho get it's signal? Are there higher voltage pulses?

[Matty]

Sounds like they should do the job spec wise.

I tried them today on the coil signal inputs to the ecu and i couldn't get the tacho to run. I also tried it without the capacitors on a single coil and still no luck, anyone any ideas of what else to try? Also tried the output channel on the ecu and that didn't drive the tacho either?

To try and get it started I decided to just bridge the relay, I got a few pops and bangs so heading in the right direction. Next job is to check the ignition timing, but never tried with cops before so no idea where the signal is taken from?

[tubbyG]

What ecu are you using? (megasquirt?)

Is the Crank sensor getting a good signal from the trigger wheel?
The vr sensor I use can be quite temperamental and play up and give funny outputs if not 100% set right/aligned.

[Matty]

I'm trialing a speeduino ecu on mine. It's uses the same megatune software to map it, I'm also running VW COPS on mine, so I'm not sure if that makes a difference to the current seen at the ecu pinouts? The VR is working well, I always get a cracking RPM signal, I can see the plugs sparking to certainly getting a signal from the ecu. i even tried tapping into the live side off the coils instead of grounding side.

If I connect a wire up to the White wire on AEI plug and dab that to 12v I can get the Rev counter to move, I am going to try it today on 5v and see if it still moves. I'm really not sure what kind voltage the Rev counter needs to make it move?

[Matty]

I got mine started today, needed a lot less fuel than I though it would!

Req fuel set to 5.3 @ 3 bar pressure,
460CC injectors,
semi sequential firing,
the Fueling map is set around 35 at idle/fast idle, I just did a 5 X 5 section all the same value
Ingition unknown at the moment, due to not being able to check it
ASE around 40 @ 10 degrees C
Warmup enrich set to 150 at ambient temps
After start taper around 300 at ambient
Cranking rpm set to 400

These got it running, but I literally ran it for 20 seconds as I still need to add coolant etc... It fired up staright away an hour later at this too.

Does anyone know what voltage the Rev counter/pump relay need to see to operate? I currently only have a ground signal avaialable but I have been given circuit diagram to transfer this to a + signal, but I need to know Voltage to spec restor size.

[tubbyG]

Great to hear you had it running briefly, Its always a nice feeling when it starts coming together .

Unfortunatley I cant add any worthwhile info on the voltage.

I found the diagram that I folowed when installing my nodiz.

[Matty]

Thanks, yeah that's exactly what I have wired in at the moment.

I did a bit of a crude test this morning, and rigged up a 5v supply, dabbed the 5V on the speedo wire (AEI plug)and nothing happend. I did the same test with 12V and it flickered.

I think the issue is that my coils ground through the block, and only the low voltage signal grounds through the ecu, so not enough of a spike to trigger it.

I think If I can amplifier it, then it will be ok. And hopefully I can use this the trigger my timing light to check the timing. I Have to admit despite doing electronics at school it's not my strong point! Fortunately my father in law mends circuit boards for a living so I'm going to pick his brains.

[Matty]

I think I need something like this off each trigger wire.

[Woznaldo]

I found that I was getting massive over-fuelling on cyl#3, so I pulled the injectors and set them up over a bucket. When I turned the ignition on and got the 2 sec priming pulse, fuel came gushing out of Inj#3!! I think this has been the source of my issues.

Getting injectors cleaned and flow tested. I'll replace if necessary.

[Matty]

Just sent you a PM Woz.

This is the Rev counter drive circuit I used in the end.

[Woznaldo]

I had the injectors cleaned, but #3 couldn't be saved. I ordered a new injector and it arrived a couple of days ago and has already been fitted. Worryingly, it looks a little bit different to the one I originally bought, which makes me think they may be replicas?

I'll crank on anyway with the start up tune and possibly source another three genuine 968's just to be safe.

Here's the genuine inlet:


Here's the 'other' inlet:


Here's the genuine non-PN side:


Here's the 'other' non-PN side (suspiciously empty?):


We live and learn.

[Woznaldo]

Also found this image from a local injector supplier:

https://www.injectorsonline.com.au/w...l-injector.jpg

[Matt Cole]

It does look like a pattern part. Be interesting to flow test it to see what it's like compared to a real one!

[Woznaldo]

My run of bad luck continues! Matty sent me his Fuel and Spark tables, so with the new injector fitted I thought I'd have another crack. The car tried to start and almost got there, but when I checked the #1 plug for the second time it was still dry. When putting it back in I got the dreaded tighten then it went loose! Freakin' threads are stripped!! I know how delicate these heads are so I'm always gentle?

So it will be a while before I have another crack as I have to pull the head off and then get a helicoil repair kit for an M14 x 1.25 thread?....

[Matt Cole]

My run of bad luck continues! Matty sent me his Fuel and Spark tables, so with the new injector fitted I thought I'd have another crack. The car tried to start and almost got there, but when I checked the #1 plug for the second time it was still dry. When putting it back in I got the dreaded tighten then it went loose! Freakin' threads are stripped!! I know how delicate these heads are so I'm always gentle?

So it will be a while before I have another crack as I have to pull the head off and then get a helicoil repair kit for an M14 x 1.25 thread?....

Oh no!I had that once. It wrenches the heart out!! At least it can be repaired. You could try a thread chased tool to see if you can get the threads back.

[Matty]

Ah what a pain!

You can get that size thread insert, I looked when I was going to repair my Gordini head.

My advise would be to put it on a mill, and clock the head over the correct angle to drill it out. I wouldn't risk drilling with a hand drill.

[Woznaldo]

I've got a kit that is specifically for spark plug thread repair. It comes with one piece reamer/tap. The combo tap has an M14 x 1.25 tap that picks up on what's left of the threads followed by a reamer and then the tap for the helicoil. I've seen quite a few companies doing this sort of system now. I think it was developed by German firm Volkel (but the kit is know as V-Coil).

The real question is do I helicoil all of them now or just the stripped thread??....

[Ian S]

Did the thread just strip out or did you over tighten it? IIRC, 22ft lbs is what is stated so I always use a torque wrench to make sure I don't turn it to hard.