Car Gets Slow Randomly, Have Datalogs.

[Rolls]

So some days my car just feels really quite slow, even if its 10c outside (normally ridiculously fast) it feels doughy with the throttle and it dies in the ass by about 6k as if the ignition has been pulled. Boost rises normally and it revs cleanly with no missing.

Car currently has a 6k rev limit due to standard injectors and afm on an rb25det with gcg highflow running 10-12psi. It is going in for retune in a few weeks but I did a datalog with ecu talk for fun tonight when it was getting slow. Was wondering if someone with some tuning experience could look at it and see if it looks like it is pulling timing? basically its a full throttle run from 2k to 6k. I throttle off at the 5787 point hence the large drop in timing.

Edited August 5, 2010 by Rolls

[Rolls]

No one got any ideas?

slowly getting all my bits and it should be off to the tuners in a week or so.

[ClutchBurndout-:(]

is 5.7rpm when u backed off? or is that the issue? where it slows down

edit, re read nvm

it almost looks like it goes into a limp mode?

[Rolls]

it almost looks like it goes into a limp mode?

Why is the ignition timing that low that it suggest limp mode? It however does not get rich when I get high in the rev range, also when its fast or slow neither blow black smoke.

I'm replacing the AFM with a Q45 (got it cheap) when I get it tuned so it will rule this out as being the problem. The volts go all the way up to 5.1v when I've been looking at the datalogs so could it just be the AFM maxing out and the ecu pulling timing because of that?

Edited August 18, 2010 by Rolls

[lachlanw]

the airflow meter is maxed out = shit timing = get it tuned and dont run it on full throttle = who ever told you to only rev it to 6000 = tard

[Rolls]

the airflow meter is maxed out = shit timing = get it tuned and dont run it on full throttle = who ever told you to only rev it to 6000 = tard

It has a rev limiter at 6000, it was tuned and the afrs are fine all the way to that 6000rpm redline. It was just a safe get me by tune until I passed inspection and got it regod with the 25 and could fit all the other gear up. The injectors only get to 80% duty cycle so theres more in them still.

So does anyone actually know roughly what sort of timing I should be seeing at 6000rpm on full boost? I'd like to find if its something else thats faulty and replace it before it gets tuned again, don't want to book it in only to have them spot it for me immediately. If it is the AFM though then no big deal.

Edited August 18, 2010 by Rolls

[paulr33]

it looks like the normal rich and retard in the stock ecu when it picks up too much airflow meter load

have you got a non-std ECU or hacked ecu or remapped ecu (ie to remove the std airflow rich and retard)

also Q45 is ass, i wouldnt even bother, sell it and go for a std Z32 and be done with it

proven results time and time again and youll have less hassles and save time/money

[Rolls]

I've got a nistune in an R32 ecu running the rb25. Why do you say the Q45 is ass? I haven't got it yet but a mate has a brand new one with plug he was willing to sell for $100, thought it was a better buy than $250 for a Z32.

I've heard it has less resolution than the Z32 but should be fine for a 250kw application. Cheers for the comment though paul, I guess being as the weather is colder now is why it's picking up the RR part of the map when it didn't used to. I'm assuming they only remapped the mid/lower parts of the map that it reached on the dyno and left the low timing/rich bits for safety up top. It doesn't puff black smoke and misfire like the standard RR part of the map though, so they must have pulled some fuel out.

Edited August 18, 2010 by Rolls

[paulr33]

hmm thats odd, im not even sure HR32 ECU has R&R mapping inside it ?

from memory it was only ECR33 ECU that has this feature in it, can anyone confirm?

but thast what it looks like, your AFM peaks near 4.7v and kablammo it drops all the timing on the floor

the Q45 is ok if you only want 250rwkw but for most users its annoying because its bigger, different plug, it's large so you ahve to change pipework, POD etc and caps out well before a normal Z32

[Rolls]

hmm thats odd, im not even sure HR32 ECU has R&R mapping inside it ?

from memory it was only ECR33 ECU that has this feature in it, can anyone confirm?

but thast what it looks like, your AFM peaks near 4.7v and kablammo it drops all the timing on the floor

the Q45 is ok if you only want 250rwkw but for most users its annoying because its bigger, different plug, it's large so you ahve to change pipework, POD etc and caps out well before a normal Z32

Well he copied the standard rb25det base map onto it and the modified it, I thought the R&R feature was technically not a feature and just the upper load/rpm points on the fuel/ignition maps where it just dumped fuel and pulled ignition? In some datalogs the AFM voltage gets to 5 - 5.1v so it is definitely maxing out at times.

However my issue is it is pulling power across the board, it is more noticeable around 2-3.5k where it jsut feels like it is making 20kw max then about 4.5-5.5k the power kicks real hard and then dies again by 5800rpm. It wasn't always like this and the turbo is making decent boost by 3k so it isn't a characteristic of the setup.

I realised the Q45 would be annoying but I need a new pod/adaptor anyway, and it comes with a plug to suit so it is only one 90 to 80mm reducer I would need to adapt it, but I might re-consider it as I haven't bought it yet.

Edited August 19, 2010 by Rolls

[kjb_r33]

I Had a 32, with nistune, and it did have both knock maps (what you all call R & R maps)for fuel and timing. These maps are accessed relative to signals from the knock sensor, not air flow meter.

[paulr33]

yeah so HR32 ECU does not have R&R feature for excess airflow meter load

but it does have factory knock map / low octane penis fuel mapping

when you tuned the car

did you tune the low octane map also

when you log do you see knocking

it souinds like its running well

picks up a fair amount of knocking and reverts to low octane penis fuel map

which is where all your power goes out the window

[Rolls]

I personally did not tune the car so I don't know if they touched the low octane map, I doubt they did as it was just a quick safe tune. The knock levels never really went over 30 when I was datalogging, is this considered high?

[MrR33666]

it does look like knock map

maby dud batch of fuel?

[Rolls]

it does look like knock map

maby dud batch of fuel?

Thought that but have been through 2 tanks of BP premium and 1 of vortex 98 with it being slow about 90% of the time, some days it will random switch maps and absolutely hoot for a few hours, then back it goes.

I guess the only real test will be when it goes on the dyno with all my new bits.

[paulr33]

dont know what level the ECU consideres high to trigger low octane map

but a knock of 30 at 5000rpm might be enough to trip it

[Crans]

The r32 GTST ecu does have a kind of r&r based on the TP(Load) you are running the last load column in the fuel and ignition map is extremely rich and retarded. There is also a TP(Load) limit map set to 128 as default. this will cut fuel causing total loss of power. The knock maps have nothing to do with the r&r we are talking about they are a fuel map that is very rich on all cells and an ignition map that is retarded on all cells.

Your timing looks pretty normal. This is obviously the timing that Nistune is reporting but have you checked and confirmed with a timing light?