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Technical Megasquirt

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Technical Megasquirt

If i disconnect TPS before powering on it goes to something like 46%. Will have a check over things tomorrow, but not much to cock up with TPS, but 0 when undone while powered.

Wideband is now set to between 10 and 20 as advised on MS and with megatunix on the wideband itself.
 
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"Note that if you have not connected a TPS to your MegaSquirt® EFI Controller, (testing in car, for example) the TPS value will slowly creep up to a maximum value, and O2 correction will be disabled. You should check that the tuning software displays approximately the correct barometric pressure when no vacuum is applied."

From the assembly guide. My bad.

No time to look further for you tonight. Soz
 
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TPS sorted. Had grounded it to the chassis rather than through MS and it didnt like it. Barometric pressure is correct at around 100.

However taken a step bakwards and it really doesnt like starting. Starts, runs for 2 seconds then dies. :bang: As it gets warmer it seems better so would that be an afterstart enrichment problem?
 
Raise WUE 5 points each cell, until it keeps idling right and get an AFR of about 14:1. Then tune VE table and then retune ASE and WUE so you get 14:1 till fully warmed.
 
Also, looking at your logs, PW and Duty Cycle are very spiky with large "dropouts" that will play havoc with tuning!!!! (actually it's enriching the PW)

They coincide with the Accel:Y light coming on.

Now, this shouldn't have any effect as far as I can tell. Deceleration fuel cut should not be working. AE should not be working, but I'm 100% sure you're getting some for of enrichment.

Now I'm not 100%, but this is probably as your TPS is going negative.

Run another log with the now stable and fixed TPS and see if: ACCEL:Y comes on, and if PW / Duty cycle are looking a lot smoother.

Kristian

//edit -- I'm gonna post this log on www.msextra.com and raise it for the devs and see what they think. Possibly a firmware "bug", though TPS should never be negative so it's not a typical case.
http://www.msextra.com/forums/viewtopic.php?f=101&t=41565
 
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Have a couple of tiny datalogs from yesterday when i couldnt get it to idle, but Accel:Y is not coming on like it was (even while cranking). From what i can see PW's look a fair bit flatter and AFR looks alot better too.

So from what i understand then i need to start again regarding the VE table as the Accel:Y was richening it up bigtime, hence why i needed to hugely reduce the numbers. :rolleyes:

Sound about right? Is Accel:Y just saying that accel enrichment is being used?

Also from what you are saying the TPS shouldnt have made much difference being grounded to the chassis. Suppose it does say in the manual to ground to MS to avoid noise.
 
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Still not right. Really getting fed up with MS now. :mad: I know its my lack of knowledge however.

Best log ive got so far. AFR going that lean suggests that somethings amiss surely? Will not keep idling either.

View attachment 2011-07-30_19.20.11.zip

Had a look at photos of flywheel and the mark was taken off so will need to make my own when i get that far.
 
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I already expressed my opinion on MS and each day you struggle makes it stronger (n)

But I did not want to depress you. I would suggest checking your injectors (do all of them actaully work?), fuel pressure, pump and alike, if not done 100 times already. Not being able to get AFR right by modding the tables back and forth would suggest to me that there could be something amiss mechanically.
 
Yeah, know where you are coming from, but i know it will be worth it in the end to be able to adjust things when i want to and eventually know how to. Also the satisfaction from actually completing it.

The engine was running fine on the 1.2 16v ECU and i did have it idling a while back on MS, even if it was rough. Fuel pump is pretty new as are the lines and tank. Pressure seems fine and SARD FPR is new.
 
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So just make sure that all your injectors are spraying and spraying properly to rule out mechanical problems with fueling.

As a side note: people sometimes get too concentrated on the wiring / ECU problems blaming all problems on management assuming they got everything else fully right. I have a recent example of a bloke having a totally messed up MAP sensor resulting in an extreme rich running on idle and blaming the ECU mapping instead (y)
 
Got it idling again. Just, And i mean really really roughly. Messed with alot of the VE table and required fuel so completely different.

How quick does the AFR react to everything?

Going from this i should be looking at increasing the VE numbers quite a bit around the lower RPM's or am i completely wrong?

View attachment 2011-07-31_20.57.35.zip

Does anybody have a Megalog viewer log of a N/A that i can have a gander at to see what to look for.
 
I didn't have enough pins left for all the outputs i was using. A bit of brute force ripping the connector apart, a bit of bending, and a bit of epoxy and here we go. Not pretty, but will get the job done :)

IMAG0159.jpg
 
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