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waynos

megasquirt help needed (NEW VIDEO ADDED!)

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right ive just managed to open the throttle a bit. there is a screw that the throttle rests on. All i did was screw it in more and now the throttle is partway open.simpler than i thought! im hungry and tired so i wont be doing anything else tonight lol more updates tommorow!

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BIG UPDATE!!!! :D

 

ive finally got it to idle!!!! im so happy. it needed more fuel, also increased the cold cranking pulswidth and slightly more ignition. the idle isnt perfect as the car warmed up pretty sharpish but at least it runs! really need to fiddle with the afterstart enrichments and warmup enrichments too. Every bit of advice dave gave me was bang on, wouldnt be this far without his help.

 

quite a wierd feeling that ive put together the brains of my car and it actually works!

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8) 8) Good stuff!

 

I'll be using this thread as a reference source when I'm attempting to get the same thing running from next weekend on!

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kool , if you need help just ask. i cant tell you how happy i am! I would be out there now but the battery on the laptop ran out lol. My next step is to get my bosch auxillary air valve fitted so i can permanently tune and set the idle

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Superb! You can come and do mine next month then? lol

 

Seriously though, this is excellent reference material for all the V-dub squirters out there.

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right after much fiddling ive got the aux air valve on,suprisingly it works very well.

 

heres a pic - if you follow the pipe above the pressure gauge (which comes from the intercooler) it goes through the air valve and into the inlet manifold

 

DSC00185.jpg

 

now im having few more problems the first is that i cant get a factory like start. after a bout 5 or 6 seconds cranking it tries to start then gradually catches and idles nicely. is there any settings i can adjust to fix this? the next problem is that after its sat idling for a little bit .it starts hunting (afr readings fluctuating with it) then it just dies! if you restart it does the same thing. The final thing is if you try to rev it, its very slow to respond like a lag kind of feeling.im not sure what that could be.

 

heres the log

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Nice one Wayne! Not been in here for a little bit, busy at work.

 

Good news then! You've now only got a few weeks of fiddling with settings to get it running nicely (only kidding! But the temptation to mess now you can is just too tempting).

 

Initial starting is all about ignition timing, crank pulse width and prime pulse. As the book says, don't try to adjust the prime pulse to compensate for crank pulse. It's just to get the fuel rail up to pressure and clear any bubbles etc in the (maybe very hot) fuel rail.

 

It needs to be within about 1% or the required mixture to catch first time, and you only get 1 go at a cold start.

 

Looks like the warm up enrichment is falling off too quickly. The AFR goes lean but just before your injector pulse width has started falling. Increase the warmup enrichment a little at that water temperature and try it.

 

Revving up needs ignition timing and fuel. The ignition needs to advance when you open the throttle and I can't see any change in your logs. But also the MAP reading doesn't change much when you part throttle so you many need some more sites in your map at about 35-40-45-50-55 kpa. Then you can setup ignition advance of an extra 10 degrees ish when you crack the throttle open.

 

Great work, feels good when you did it all yourself :D :D :D

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thanks for the advice will give it a go tommorow with the pulswidths.when u say u say it needs to be within one percent do you mean 1 percent of the required fuel figure? once ive got the starting sorted i will move onto the ignition timing

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Warmup enrichment within 1%. Takes some getting right but it's the difference between leaping into life and what you have now.

 

I forgot to mention that if you run the tuning of the ignition table you can watch the little dot moving around when you open the throttle. Watch how it moves and tune the sites it moves through with the more advance the closer to 100kpa it gets. Hope that makes sense?

 

You're right though, get the idle stable first and then move on.

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right it now starts better, just a lttle initial throttle and it bursts into life! chuffed about that. it now idles too. i still have the problem with reving, if i accelerate slowly its ok but if i try to rev it quickly there will be a delay before it actually does anything.if i put my foot down too far it just dies.Been looking on the msefi forum and i may need to change my acceleration enrichment settings .Forgot to get a log! doh! shall upload a video of it running off my pho ne

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oh and i almost forgot, the original coolant sensor was giving some strange readings before - like 160 deg c or more when warm! i had an old polo coolant sensor knocking around nd decided to give this a go. managed to get all the resistances at different temps to put into megatune.

 

just a quick how to

 

got a t piece from homebase

tpiece.jpg

 

some coolant pipe and two circlips

clips.jpg

 

heres the sensor

coolantsensor.jpg

 

and the finished article

newcoolantsensorholder.jpg

 

i placed this inline with the coolant pipe that comes out the side of the block. It reads much more acurate and responds a bit quicker to temperature changes

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cheers for the comment dirtytorque ,slowly getting there! i havent got a back box on the car at th moment thats why its a bit loud

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lol this car is annoying me, i still cant get it to rev properly. ive tried loads of different ignition maps with no sucsess,even tried moving the dizzy to see if that made any difference. im pretty convinced its the acceleration enrichment settings but i have no idea what i need to do to get a better response

 

heres the settings

accel.jpg

 

and a couple logs

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acceleration enrichment should only come into play with rapid throttle openings.

if you just gradually open the throttle does the engine rpm increase in a linear fashion?

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yea i can rev it very slowly but if i try to blip the throttle it hesitates then revs.if i could get my head around what everyhting means i reckon i could sort it. ive also noticesd the afr goes lean when you try to blip it

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i wish i could help more but I am a couple of weeks behind you.

I would try and use the logs to home in on the point where it stumbles and see what the engine inputs are the telling you,i.e what is your lambda sensor telling you?

Does it matter if the engine is cold or hot?

Are you happy with your VE table?

You should really tune VE b4 attempting Ae apparently.

Hopefully Crazydave will chime in and help you.

Good luck.You'll be an expert by the end of this,then you can help me get mine running.

:)

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think ive given up on this.cant get anything to work right so i think im just going to break the car and ge a nice g60. Cannot get the car to rev no matter what and about 5 mins ago i had it running it cut out, all the lights on the ms stayed on and the fuel pump ran on. oh well was worth a try - just a very expensive lesson learned!

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think ive given up on this.cant get anything to work right so i think im just going to break the car and ge a nice g60. Cannot get the car to rev no matter what and about 5 mins ago i had it running it cut out, all the lights on the ms stayed on and the fuel pump ran on. oh well was worth a try - just a very expensive lesson learned!

Dude, don't quit now. It just requires some time. You've done soo much already, its the last hurdle.... :(

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ive tried everything i can think of.i was so close to smashing the ecu to bits.Doesnt seem like it will ever work

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ive tried everything i can think of.i was so close to smashing the ecu to bits.Doesnt seem like it will ever work

 

If you have a stim power up the MS box independently of the car and check that it is functioning correctly.

You can't give up now.

 

I won't let you. :D

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yes i powered it on the stim straight after, got the same thing all three lights on.wiped and reladed the firmware but i just cant be bothered no more its drained me

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yes i powered it on the stim straight after, got the same thing all three lights on.wiped and reladed the firmware but i just cant be bothered no more its drained me

 

 

I understand.

Cool.

Take a break and let us know what you decide.

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