Landrew

iTrader: (2)

Reverant,

Since the microsquirt module is a solderless plug in swap, if we can confirm the U6 injector driver had failed would we be able to just swap that board? That would be a very painless operation on my end to resolve this.

Look forward to hearing from you.

deezums

iTrader: (3)

I don't think swapping a microsquirt card is solderless, I think you need to solder headers to it.



See the long strip across the top, and the little strip on the left (J1/J2), those will likely need soldered.

If it's just the actual injector drivers, you could replace the two transistors (u6/u7) the black square things mid-left on the board. I posted the link for replacement drivers earlier. There's gonna be two more of those somewhere else in the ECU if it runs sequential, too.

Braineack

iTrader: (62)

when you reloaded your old tune, did you go back through and make sure all the settings were correct, specifically the injector/fueling settings/banks?

the microsquirt module only has 2 injector drivers, the rest run off an additional (2) that Reverant added inside the case.

if only cly #3 is firing it sounds like U7 is working correctly, but you now have "additional drivers" and sequential fueling disabled in your msq so #2 and #4 aren't firing. This also suggests that the new firmware didn't the problem with the injector driver.

I highly suggest next time you have an issue like this, dont reflash firmware in the middle of diagnostics, it only adds another level of variables and more frustration.

Landrew

iTrader: (2)

Sorry I assumed that sequential was only used for modified ignitions not ever on the stock setup. I'll switch and test this morning.

Yes one problem at a time is the best way to diagnose. I was hoping that the flash would resolve the issue.

deezums - I'm ordering some of those U6 this morning.

Braineack

iTrader: (62)

it's should be an incredibly easy fix, even for someone who's never soldered before.

Landrew

iTrader: (2)

Yesterday after getting mad - I calmed down and said - hey another week or 10 days or so at the worst case if I have to get an entire new MS3 I can handle that.

Now I'm eagerly awaiting the chips and foresee a few days (depending on shipping) to feel 25% more power using all the cylinders to power the car.


You guys are awesome here !


BTW can you explain the untimed injection vs sequential if I'm on stock coils etc ?

Landrew

iTrader: (2)

Deezums - maybe I didn't read your post fully because you drive a yellow girls car.

Who would do that............

Landrew

iTrader: (2)

I've soldered 2 wires sometimes clean sometimes globby.

I know words like Radio Shack, Weller, tinning, rosin and flux. I can tell you I like lead solder better than the lead free new stuff. I've even soldered copper pipe, but PEX is way easier.

I've melted big globs of solder and let it fall to the ground on purpose then stared at the beautiful pattern and wondered why when I live on an acreage does our dog still poop 30 feet from the house.

But,,,,,,, I've never desoldered nor soldered on a precision board. Time to get one of those suction bulbs and do some reading / practicing

Braineack

iTrader: (62)

all you gotta do is heat up one pin at a time and pull.

heat up the leg, and lift it off pad.
heat up the second leg, and lift it off pad.
heat up the rear tab and pull entire thing off board.

pretty much just do reverse to install.

Reverant

iTrader: (10)

Just cut off both legs of the transistor, desolder and remove them one at a time, then heat the large tab of the transistor and pull the transistor off. Make sure to buy some desoldering wick to remove the excess solder.

Joe Perez

iTrader: (8)

Ignition coils have nothing to do with it.

In sequential injection, even if the injection is not precisely timed, the goal is to have each injector fire only once per engine cycle, and for the temporal relationship between the timing of the squirt and the intake cycle of its corresponding cylinder to be the same across all cylinders.

This is done to improve the overall efficiency of the engine, by eliminating (or at least reducing) imbalances in VE between the cylinders.


In batch injection, the customary pairing of injectors is not what you'd expect based on the firing order. Typically, cylinders which fire one after another are paired, which for us is 1&3 and 2&4. At very low loads (when injector duration is short), this means that after being injected, the fuel is going to sit for slightly longer in one intake port than the other before being drawn into the cylinder. This creates a very slight imbalance, decreases idle quality slightly, requires slightly more fuel to be injected overall, etc.

In the grand scheme of things it's not a major issue, but something which can be done better.

Landrew

iTrader: (2)

Thanks for the explanation. I was including injection with spark in my interpretation.

I made a Digikey CAN purchase and after watching a tutorial picked up some wick


Rev- is there only the single U6 to worry about in my build?

Joe Perez

iTrader: (8)

Nope, sequential ignition is another matter entirely.

The point of sequential ignition is merely to decrease the load on the coils. If you have one coil per cylinder, there's no harm per-se in that coil firing twice per cycle (once at TDC between compression and power, and once again at TDC between exhaust and intake), it's just unnecessary. It creates some extra heat in the coil, and (in theory) can be a limiting factor in dwell vs. RPM (more dwell time is available if the coil only fires once per cycle), however in practice this is almost never of real concern.

Or, put another way, there's a reason that two-coil batch ignition lasted well into the 21st century despite ever-tightening emissions standards. Assuming the coils are appropriately designed for the application, there's virtually no functional difference at all between the two modes.

(It could be argued that when we do a COP conversion of a Miata, if we do not switch to sequential ignition then we are operating the coils outside of their design criteria by firing them twice as often as they would have in their original application. So they might only last for 100,000 miles instead of 200,000 miles.)

Landrew

iTrader: (2)

I like the cut of your jib

Landrew

iTrader: (2)

Rev can you send me all the applicable settings I'll need to default to. Will I need special firmware with my MS?

Joe Perez

iTrader: (8)

To be clear, when I spoke earlier of island-hopping around the Caribbean, I was referring to a motor-yacht. I have very near zero sailing experience.

Landrew

iTrader: (2)

Ha,

Have you ever set sail for a 3 hour tour, a 3 hour tour ?


Since the electrons flow well with you what capacitor would could replace this battery? A 12V 4Ah 80CCA Please note that I do not actually need the starting amps I just need a pass through device as we kickstart the mini bike and we dont need 10bls hanging up and at the rear of the bike. All that polar mass is wasteful plus the battery is dead and I'm cheap.

Landrew

iTrader: (2)

DigiKey says it will arrive tomorrow by 5pm. That's fast.

That is amazing service for $8 Canadian shipping. I had no idea that they had a CAN site in CAN dollars with a third the price of shipping ($20US to Canada vs $8CAN) Found it when searching for the desoldering wick. Same company they just have a nice setup for all the Canadian orders. Who knew we had people up here were into transferring electrons. Semi Conductors do like the cold though.....
I'll be learning a few things this weekend.

deezums

iTrader: (3)

Methinks it would take a quite massive capacitor to store 4ah worth of 12V.

If I'm not mistaken, that's an impossibly huge capacitor. Maybe a deal for supercapacitors though, if I'm not mistaken if you strap these up in series you'd be a little under 1/10 the total capacity of that battery, with a lot lot more 'CCA' lol

6pcs Farad Capacitor 2 7V 500F35 60mm Super Capacitor | eBay

Landrew

iTrader: (2)

Its a mini dirt bike, once the machine is kickstarted it is producing voltage through the permanent magnet magneto. I found out there are a few places that sell "Battery Eliminators" but I knew they were just capacitors in a fancy package. I just was not sure the size needed for our little bike to replace the battery. Im not running any lights or other consumers on there. Since it has a battery it must be putting out a decent amount of watts from the magneto to be able to charge it. So once its started by foot it is self sustaining. The battery being lead acid is probably 10% of the bikes weight and since it sits through winter there is maintenance neded on it.
No one with a Miata has time for that.