Any Megasquirt vets on here?

[westco4k]

Yeah starting from scratch would put you pretty close to 1000 i bet.

Mine is running good, still having issues with my wide band sync and I plan on moving my tps to the throttle body since it is a little erratic mounted on the linkage. Other than that I'm just trying to have it ready for the vw drags coming up this month.

Keep us posted on the potential startup! I feel like I could count the 20v megasquirt cars on one hand. And I bet all of them have posted in this thread!

[deaner]

Yeah, and from scratch/starting fresh is how I'd go about it likely. A whole PNP MS system would sell easier anyhow lol. Anyhow, stinks you're having issues. Sounds like you've got a good grasp of what needs to get done though, which is always nice. I hope you get 'er sorted for the drags!

Little update: so I pulled the line this morning and got INSANELY lucky! It was clogged right at the hose connection going back into the tank! That never happens haha! I took a pick and dug out what I could, blew it out then added some heat to gum it up some and then finally took a pipe cleaner and got the rest of it. Put it all back together and boo yah! Still need to fix a couple leaky injectors but the fuel crap should be done here in a bit. I'm letting the pressure bleed off right now so I can pop the rail. I'm going to skip wiring the wide band today and just plow through to try and get it to start later. Woohoooo!

[DE80q]

Yeah, these 20v fuel fails are known to leak if not perfectly positioned. I'm glad to hear the clog was easy to remove.

[deaner]

Yeah I figured they'd leak a little bit. I had to "reengineer" the adaptor fittings from the 4k fuel line. They'd used the wrong adapter. It didn't have the chamfer/flair for the compression sleeve, so I grabbed a step bit and made on lol. Got all the fuel leaks sorted. Not a drop anywhere....except the fuel pressure gauge. It's a pretty big drop. Dumps all 35ish pounds in 30-60 sec. I thought maybe I had a stuck injector or five but the cyl were dry. I'm figuring the FPR is gummed up or has a hole or something. I'll pull it apart later.

So I went to start it! I Changed the oil, doubled check everything and rolled it over. Nothing. Had a hankering something hardware wise was maybe wrong so I pulled a spark plug and it was dry. Ok... Then checked for spark and got one flash. Oooooook......
Checked all the ignition stuff and it looked fine. Rolled it over with a test light on my 12v power connections to make sure I was good on "power while cranking" and their good. Then I found a problem. This connector on the dizzy has bare wire that was shorting inside. I'd seen that it was siliconed back on and I assumed it was from taking it apart to lock it so I didn't thing toooooo much about it, until now. If you look closely at the red wire, you can see it. I noticed with the key on, when I wiggled it, the fuel pump would cycle. Being as the hall is powered from the same source as the ECU, that would explain my issue I reckon? While its cranking it's bouncing back and forth to a short to ground and resetting the ECU.
Sound like a decent theory?

[elaw]

That theory does sound sensible... it's surprising it didn't blow a fuse!

Hopefully a little RTV can take care of the wire but... is the connector well attached to the dizzy? It looks a little iffy.

[deaner]

Man, I really need to start proof reading my posts when I type them up on my phone.... Haha.

That's what's perplexing me Eric. How didn't it pop the fuse? As for the connector, no. It's not well attached at all lol. It had previously been kind of rigged together and now I'm thinking of just getting a different dizzy. I may goop it up with silicone for testing purposes in the meantime though.

Something I was thinking about too, after trying to figure out it not injecting is, at what point does MS start injecting fuel? I vaguely remember reading somewhere that MS needs at least 300? With a charger on the battery, the RPM gauge on the laptop wouldn't go past 150rpms. It would kind of bounce between 145 and 150rpm, but never over. Everything sounded normal when rolling it over with the starter and before cranking for the first time, I rolled it over by hand to make sure everything was still free.

[elaw]

Well my ignorance of MS1 is going to show a little here but I can say one thing for sure: there seems to be a popular misconception that Megasquirt requires a certain RPM before it will start injecting fuel and that's not true!

Here's how it works on MS2 and MS3 and I think the fundamentals are similar on MS1:
1. Depending on configuration, at key-on it fires all the injectors once as a "priming pulse". The width of that pulse is configurable by coolant temp so you can inject more fuel when the engine is cold. The fuel pump also runs for 1 second.

2. With a distributor-triggered system, the MS will start injecting fuel, sparking, and energize the fuel pump as soon as it sees trigger pulses. There's a "skip pulses" setting that can make it ignore the first few pulses (to protect against noise) but typically it'll come to life after less than one revolution. With other trigger schemes, it may wait until it gets "sync" meaning it sees a specific trigger pattern (like missing teeth on a 60-2 wheel) so it can know the crank position. But again there's no RPM threshold. The injector pulsewidth during this time is taken from cranking tables and is dependent on coolant temperature. Ignition timing is usually fixed also (not taken from a table or anything).

3. There is a "cranking RPM" setting, and I think that's what confuses people. That setting is the threshold between "crank" and "run" mode. During starting, as soon as the engine goes above that RPM (usually around 300), the MS switches from crank to run mode, and starts computing injector pulsewidth and timing based on the regular running tables and other settings.

So the bottom line is that as long as the engine is turning at all, you should be seeing injectors firing and spark.

The one thing I'm finding confusing in MS1 is I can't find a "cranking injector pulsewidth" table like MS2 and MS3 have. As far as I can tell, MS1 uses the "priming pulsewidth" table for that (so cranking pulse = priming pulse).

[deaner]

Ahhhh that makes sense now about RPM table switching. Thanks for explaining all that to me!

I think you're right about the "cranking pw" table and "priming" tables being the same. It took me a little bit of back and forth to make the connection yesterday lol.

[mr_aj_johnson]

25 foot roll of aluminum line is like 30 bucks....

[deaner]

25 foot roll of aluminum line is like 30 bucks....

Yeah, I saw that.Being as I was able to save the line and not steal the one off the rally car, I'm going to hold off redoing the fuel lines on the rally car. I figure when it's about ready for stage duty I have to patch up/make a new rear firewall anyhow, I'll do the fuel and brake lines at the same time.

[deaner]

Small update.. Being as awesome as he is, DE80q sent me a couple of spare dizzys to test out. Sure enough, mine was FUBAR. Plugged one in and spun it by hand to listen to the sweet sound of clicking injectors lol. Well, 4/5 injectors... Ones either bad or just stuck. Ill sort that out after I figure out this goddamn NO SPARK bs ha! After messing with it for a few hours tonight I got the coil to at least fire by manually grounding the ICM. At least now I have it narrowed down to the ECU not doing what it's supposed to. I'm fairly certain I'm using the wrong "spark output" wire to control the ICM. From what I gather is the old 2.2 boards use a different circuit and DB37 pin than the newer boards. The older board uses pin30(fidle) to control an ICM and the new boards can have the driver already installed and use pin 36(ign output). I think I messed up and followed the 3.0/3.57 diagram that came with the harness I bought. I dunno. I'll try pin30(fidle) and see if I can get this thing to makes sparks tomorrow.
So. Much. Reading. With. Mega. Squirt.

[elaw]

When you're running it on the stim, does the "IG" LED flash? That's the ignition output, which should be on pin 36.

If it doesn't, it's possible I may have overlooked something when setting up the unit - there are a few connections on the V3 mainboard that apparently aren't present on the V2.2 that could cause this. If that's the case, PM me and I'll get it taken care of!

[deaner]

I'm not sure Elaw. I was so "done" last night that I just shut everything down once I got the coil to fire manually. I'll check as soon as I get home. Thanks!

[deaner]

Awww man lol. Nothing... Email sent Eric.

[DE80q]

No!!! That sucks. Hope its nothing too bad.

[deaner]

It doesn't sound like it too much of a big deal. I sent the ECU back out to Eric to finish it up. Maybe now I'll get some time to work on the rally car ha!

[elaw]

Yeah, my bad. I "ass"umed that the v2.2 mainboard had the spark output circuitry that the v3.0 board does and that's not the case. Luckily it's easily fixed!

[deaner]

No worries! I'm getting a chance to take a break from that car and able to spend a few hours tomorrow on the rally car. I know, first world problems... You've helped me out more than you know over the past months! I'm very grateful and glad it's something easy too!

[westco4k]

its worth noting in this thread that those distributor hall sensors can be had on ebay dirt cheap and it includes a new connector that screws into the body. mine was in bad shape also. I know you already fixed it, just saying

[deaner]

its worth noting in this thread that those distributor hall sensors can be had on ebay dirt cheap and it includes a new connector that screws into the body. mine was in bad shape also. I know you already fixed it, just saying

Do you have a link handy? I hunted around some but didn't find much.