MicroSquirt.com read only forum (Jan.15,2018)

msns-extra 029q2 v3 vw 20v turbo

hi guys getting no response from anyone on my problem
i can drive my car gently through the revs nicely but if i try to load it to quickly it missfires and backfires always at the same spot on the ve map ?? picture attatched

any ideas i thought it was due to running to rich bu i can increase and decrease the bins around the missfire without any

seems very quiet around here

ive asked for some help with different things over the last week and got no response

bens_cab,

I don't know much about MSnS-E, but it sounds like you need to increase your accel enrichment to me. See: http://www.megamanual.com/v22manual/mtune.htm#accel

Lance.

hi lance

ive been playing around with the accel enrichments but it doesnt seem to make much difference

the car will idle smooth without any blips if i rev the engine it will splutter slightly then clear and rev fine

if i drive i can build the revs up slowly to much to soon and it backfires and misses lots

bens_cab,

That sure sounds like a accel enrichment problem to me (or possibly a fuel supply problem or you might have reached 100% duty cycle, I suppose).

I *think* MSnS-E has a number of schmene and limiting possibilities for accel enrichment, peorhaps someone more familiar can comment on your settings if you post them.

Lance.

heres a datalog i just did it was backfiring out the exhaust

my neighbours love me

is there there any info on what each line in the data log is the tps line does some weird stuff by the looks of it

bens_cab,

The lines in the datalog generally mean the same thing (like rpm, MAP, etc.), but some things are code specific. I see you have an entry of 1000000000 for the TPSacc, and this is something to do with the MSnS-E code, I strongly suspect.

You also have a number of events where the pulse width drops to zero (which I suspect are the misfires you are reporting), and again I think this is code/settings specific (since the datalog reports the commanded fuel pulse widths, indicating what MegaSquirt is 'thinking' - if it was a hardware problem with the injectors/wiring, MegaSquirt report normal pulse widths). Pehaps it is something like the rev limiter or 'launch control' or ...

Your duty cycle looks fine.

Lance.

when i look at the datalog it doesnt really make much sense to me i understand the basics

im not sure what to do to sort the problem out the pulsewidths going to zero concern me could that be that the accel enrichments are way off then

i dont have launch control set and my rev limiter is set at 6800 to 7000

so i dont think that is the problem

james will probally come up with a good explantion when he comes online
ive been fighting with this car since march its going for its mot inspection this week so fingers crossed

Open Megatune, goto Tools-Review mode and double check ALL your settings, especially your Overboost Protection settings.