fitted the ms yesterday after doing the board mods needed. the only one i am missing now is the pwm idle control mod, will that make a major difference to the way it runs when ms is installed.

anyway, i got it started and running on the ms, it idled very well and revved reasonably, it stumbled slightly off idle, however the afr was reading 28 almost constantly,which i thought could have been a faulty lambda sensor so dismissed it. so i took it for a small slow drive, it seemed hesitant and in need of work which i knew it would be. after it was parked up for about an hour i went back to it to do some more work, outside temp had dropped and coolant temp had dropped a little. the car struggled to start and would not idle, it was very very irratic when revved and after a short drive it kept stalling and there was a constant hissing sound from the air filter with the engine off and the ign on, after taking out the spark plugs it turned out that the engine was hydraulic locked. The megasquirt lights were also not lighting up anymore, they flashed on when ign 1st turned on but after about a second they go out and will not come back on again until the ms is unplugged and replugged in.
i have taken as many screenshots of my msq file as i can so everyone can see if my settings could have caused the problem.

 

sorry if the pics are a bit big i dont know how to change the size.
if anyone can help me i would be really grateful, i am absolutly stumped.

 

big? if anything they're a tad small mate, it'd be easier to post your .msq

 

I'd be more interested in how it's wired up-- did you rewire the whole car, part of it, build a PNP adapter, etc...?

Was the unit prebuilt or built from a kit? Any mods beyond the standard Miata ignition control mods?

Unplug your injectors. With the ignition on, but the car NOT running (obviously as the injectors are unplugged), use a multimeter to check for 12v (batt voltage) on one pin of the injector connectors, and ground on the other pin. You should be getting the 12v. You shouldn't be getting the ground. Check all four.

 

will give that a shot tomorrow.
the standard board mods off diy have been done to the board.
it was a prebuilt board from bill shurvinton, i have had to do the cas mods and the spark mods, also the vb921's were installed on the board, so i have removed the vb921's and the large black resister thing near to the db37 plug.
the ign on my mazda is standard i will post some pics of the board itself tomorrow

 

In what way was it built wrong? have you got pics of you board (front and back)

 

i have spoken to bill shurvinton and he has offered to have a look at it for me, however i want to sort it myself as its good experience and probably quicker too,so just to let everyone know there is not an issue with bills service, its been excellent, just that certain things were missed during the build.
anyway here are the pictures of my board as it stands at the moment.

 

Just a small tip if you want to take screenshots of the active window (dialog boxes etc) instead of the whole screen, use the left ALT when you press the "Print Screen" button.

But posting the file (or text from it) is even more forum-efficient.

 

i have spent all day fault finding on the megasquirt, and i have now got it running again on it, controlling fuel and spark.
it ticks over very good and starts perfectly.
the lambda is almost certainly nackered so is reading a bit skwiffy, but the main issue is the injectors, it ticks over fine but when revved it misses, and when it misses the injector pulse width just dies completly, i cannot find anyting in my settings to cause this,i have an msq file and datalog to post up but i dont know how to

 

email the .msq and datalog to Matt at websales AT diyautotune DOT com with a link to this thread to show him what's going on and I bet we can help you out...

 

i have done a good 20 min drive in the car now and datalogged it all, i will email that along with the msq.
is it just the excel file you want emailing??

 

that will be fine, along with the .msq

 

i sent the email to websales AT diyautotune DOT com
fao matt.
will you let me know what you think when you recieve them, thanks

 

Ok, I've gone over the data logs. I think it's your overrun fuel cut kicking in that makes the pulse width fall to zero. You've set it to cut the fuel off any time the RPM is over 1,400, the MAP is less than 25 KPa, and the engine is warmed up, as long as the engine has been there for 1 second or more. The fuel cuts in your data log always happen there - my guess is that the misfire is

 

ROLF that sounds about right

 

excellent, thanks matey. mucho helpful, ill give that a go now.
last problem for the moment now, when i connect the 5v reference wire from the tps it shuts off the power to the ms, all the lights go out the lot. any ideas on that???
cheers

 

Have you got a 1.6 by any chance?

edit: just searched through your posts and you do.

I have a feeling that if you disconnect the TPS all your problems will go away. My car wouldnt rev over 3500k with the TPS connected.

The 1.8 TPS is a variable one with the volts rising from 0-5v in a steady linear fashion.
The 1.6 TPS has a 5v feed at 0% throttle (so the ECU knows its not being revved), then a separate 5v feed at 100% throttle. (I'm pretty sure this is correct)

I have exactly the same problem with my install, though just leaving it disconnected seems to work fine. I have a 1.8 TPS that I'm trying to fit. There is also an article on the web about how to make the 1.6 a true variable TPS (which I'm trying to get restored from a backup) I'll point you to it when its been found.

Where abouts in the UK are you?

 

oh my ******* god, those pictures make me not want to even read the thread, lest comment on it and I have DSL ... I dont even know if I was going to comment in the first place, but if i have something to say I will edit this post.

ok, read the thread and nothing to comment, but god those pictures are both useless and annoying.

 

yeah you don't need the 5v reference line, don't bother with it.

 

Here it is http://mx5nutz.drmryan.co.uk/forum/i...65&#entry19665