skinny

i'm really struggling to understand the meaning and effect of the settings around accel enrichement (and deccel enrichment!?) in megatune.

i'm getting horrible spikes in my fuelling which according to MLV appear to be triggered by AE (MAP based, i don't have a variable TPS) under load, even though i've reduced the numbers from the stock MSPnP settings. i tried to turn AE off by increasing the MAP-based rate bins to start off at 800kPa/s but i still get really nasty spikes. (this trace is with my accel enrichments settings as normal)



the value (ms) is the time that the MS adds fuel for according to the rate, is that right? and the MAPdot threshold is the rate, measured over the Accel time, below which no AE correction will occur is that right?

as i have no TPS, i'm guessing TPSdot threshold is meaningless?

what does decel fuel amount refer to - i have it set to 100% and when i lift of the throttle above 2000rpm my fuel cuts completely, so i'm happy with that.

and in accel decel mode, what is decel enrich - why would you need to enrich during decel - is it for when you come back on throttle? and what does the Cut Decel Setpoint mean - say i set it to 60kPa, it turns decel enrich on below that MAP value?

sorry for all the questions, i've tried searching but haven't found any answers i understand! also, how can i best utilise the AE wizard?

Braineack

iTrader: (62)

where is your MAP sensor tapped into?

skinny

at the moment it's off the rear facing nipple at the front of the inlet manifold. on some advice, i bought a t-piece to allow me to tap into the outlet at the rear of the inlet manifold that the FPR uses (mk1 1.6), but when i experimented and plumbed the MAP line into the FPR nipple and connected the FPR up to the front of the inlet manifold, it didn't clean it up by a massive amount. i'll do the t-piece tonight tho and make a log of it.

Braineack

iTrader: (62)

Teeing off the FPR is best. The nipples off the TB are very turbulent.

skinny

ok so i changed the MAP line to T into the FPR hose last night, turned off AE and made the MS operate under open loop so that i could tune the VE tables. obviously under accel i'm getting a lean condition briefly so i'll just start small and increase the AE numbers until i maintain my AFR targets with tip-in.

but looking at the log, i'm still getting a really noisy MAP signal under load (cruising it's nice and smooth).

i guess the only thing i can do now is fit some kind of filter in the line to clean it up and hope it doesn't kill the response time etc...? i've just read elsewhere that this noisy MAP signal may be due to the turbo wastegate? so if i hook up the boost solenoid i might be able to filter it out?

richyvrlimited

iTrader: (1)

Hi_res code will help with fuelling but it won't magically smooth your MAP signal.

Yes you can use the High_Res code.

Braineack

iTrader: (62)

the wastegate doesn't bleed boost, it's not the issue. noisey MAP means noisey signal.

you can install a little fuel filter inline to smooth it up.


HR code is for fueling algorithm only.

skinny

ok cool thanks for the help, i'll see if i can get a little inline filter and leave thoughts of Hi-Res code well alone for now

skinny

this is really pissing me off now. please please help!! i'm running an MSPnP (so i think it's MS1, V3), without TPS. this is not to do with accel enrichments but i thought i'd keep it all on the same thread.

as suggested, i've taken my MAP signal off the FPR line and got an inline filter between there and the ECU, and my map signal is still all over the place, just constantly up and down by 4-5 kPa, especially in cruise at around 70 mph. anything between 2-6Hz.
sometimes it smoothes out for a few seconds but then it comes back, it's much smoother at low MAP levels but still jumps around by 1-2 kPa
and it's normally pretty bad in boost although occasionally it's smooth. just doesn't make any sense at all

this is a snapshot, zoomed out to 50 seconds, in cruise. it's noisy, goes bit smoother, goes noisy again.


this is under acceleration, over 15 seconds.


what the hell is going on - frequency of noise changing from quick to slow


could it be an electrical problem - my battery volts seems to be pretty noisy....?



edit: i have a grounding kit which goes from the battery through to the engine bay and engine. could that be causing a problem?

Braineack

iTrader: (62)

yeah i was goign to say looks like a grounding issue.

skinny

ok thanks - i did clean up the original ECU ground point, can i improve that point in any way?

in the meantime, i'll try removing the grounding kit that i have, see if that makes a difference.

Freaky Roadster

Funny, I was going to suggest grounding over on NUTZ. Seems like it's quite often the cause of noisy signals.

skinny

cheers - will log my run into work tommorow

skinny

well i sorted this out actually with the inline filter, still get a little oscillation in cruise but it's 1kPa rather than 4kPa now which is more acceptable.

my latest problem is that tipping in, there's a delay before the revs start to pick up. this is most clearly shown (and felt) blipping the throttle from idle. i put my foot on the pedal, the MAP shoots up, the fuelling shoots up accordingly, but the revs drop initially before picking up. this can be clearly seen with the position line in the log - MAP is high, injector pulsewidth is high, AE has kicked in, but revs have dropped.

is this an AE problem, going from the lean spike in the AFR measurement?



i have a vTPS coming this week hopefully so should i just ignore this and wait for that, or could it be a more fundamental problem?

Braineack

iTrader: (62)

lower the TPS threshold in your AE wizard settings, see if that helps.

skinny

i've got the threshold and first MAPdot bin both at 30kPa/s, if i go lower than that i think i'll start to get false triggers as my signal is still a little noisy under certain conditions, tho i can give it a go and see what happens.

what's confusing me is that the AE can be seen in the third chart kicking in, and the fuelling rises accordingly, but the revs just don't rise at the same time. i'll try raising the AE fuel added too see if that does anything.

skinny

right, definitely getting somewhere now - have installed my vTPS and it all works correctly. trying to set up some values now but TPSdot is not a default value logged by my MSpnp (MS1).

what should the line read that i need to add to the msns-extra.ini file to record this and view it in megalogviewer - is this correct?

entry = tpsDOT, "tpsDOT", float, "%.1f"

edit: it's ok i found tpDOT in the options list of MLV