jcsbanks

Could be, you mean a mistake in the factory ROM for the US Evo 8?

Appauldd

iTrader: (22)

Yeah. I looked at several other ROMs and all are different for the temp settings; not scalings.

jcsbanks

Try changing the settings at the coolant temps where you have the problem?

Appauldd

iTrader: (22)

My problem is that I don't know what temp tables affect what other tables.

Appauldd

iTrader: (22)

It appears that th ISCV tables are set up strange in my ROM, or at lease I think they took strange....the range is form -31 to +82 C. Durring warm up maybe the ISCV is open too much causing the lean condidion. ? ? When would I ever see -32 C?....NEVER. This is why it looked strange to me.

jcsbanks

If the ISCV is open then the MAF sensor should read the extra flow and not result in a lean condition.

03whitegsr

iTrader: (8)

I grabbed a log this morning and looking at it, I'm kind of at a loss of words as every time the AFR goes lean, the target AFR is rock solid at 14.7:1. I may have gotten the idea that the car targeted leaner then 14.7:1 when I had some scaling messed up in log works. Like you mentioned, the car does not target anything leaner then 14.7:1 in this log.

The car it's self isn't all that modified. I have some parts that are definitely know to cause driveability issues. I have a Tial BOV which is obviously vented to atmosphere. I also have a 3" hard pipe intake and open element air filter. Stock injectors though and a completely stock internal motor. Just basic bolt-ons and an EVO IX turbo.

I should probably clarify. My car doesn't drive like a bucking bronco or anything. I've been tuning cars for ~10 years though and I've just picked up on the feel for when a car isn't running just right. All my drivability issues are very subtle; I'm just hoping to tune it all out. I would bet most people wouldn't pick up on the issues that I'm noticing. The lean stumble is only when the car is very cold and only for about the first minute of running. After that, it just has a very subtle stumble that you can't hear and you'd only notice if you were paying close attention to it. In other words, if you aren't looking for it, you probably wouldn't notice it.

For what it's worth, my coolant temps were 2.0 degC this morning when I started the car. Also interesting, from 60degC to 70degrC, I could feel the car transitioning from running like crap to running like normal. The only thing that changed during that time was ignition advance. I was cruising in 3rd gear at 3000 RPM and could distinctively feel the car "cleaning up" as it warmed up. You can see it in the log too. AFRs bouncing around from low 12s to mid 15s. Timing advance down at 15 degrees. 60C comes, ignition advance goes from 15 degrees to 30 degree by 70 degC. AFRs start to oscillate from 14.5:1 to 14.9:1 (closed loop).

Timing advance drops heavily every time the AFR goes lean though. Pretty interesting. I'm wondering if I'm just seeing timing advance from the warmup maps where it pulls out like 10 degree causing a lean condition. I know ignition advance doesn't affect actual AFR, but it can definitely effect the AFR you see on the wideband. I think I'll change FAA bits 9 and 10 and see how it affects things.

I'd post the log, but I can't right now.

jcsbanks

I recently cleared FAA bit 10 but it feels no different on cold start or part throttle. I think the cold manners on mine are more than acceptable for a low compression small displacement engine. No worse than my old E46 M3 anyway.

However, although I don't see the AFR excursions you report, I do notice that it picks up knock sums at 2500-2600 RPM when between 60 and 75C coolant temp, which I reduced to 1 or 2 by retuning the knock multiplier (just increased by 10% there, it is not timing responsive and doesn't happen when warm).

03whitegsr

iTrader: (8)

As I mentioned, I'm talking below 0C cold starts. Today's 2C was warmer then it's been in a while.

I set the engine coolant temp ignition trim scalar table to 0 across the board and sure enough, the car drives much better on warmup now. AFRs still bounce around a lot, but it just drives right through it now without a hick up. Timing stays around 30 degrees now under light throttle cruise instead of dropping into the teens.

Only issue is the car idles at 1500-2000 RPM when it's below about 40C.

I think I'm going to tune the ECT based ignition trim tables now and see if I can get a good balance of driveability and idle quality. I realize this table is likely for emissions purposes to get the cat up to temp quickly. I would prefer that as I still have a cat and don't want to foul it out from cold starts. I plan to leave as much ignition retard in as possible but still get good driveability.

On the warmup tables that (I believe) Mattjin posted, do we have any time scalars for the timer functions? Also, these tables are likely multipliers, and not adders, correct?

ITP

I seem to have the opposite issue with cold start. First off. The car is heavily modded with enough parts to warrant the 1000cc injectors in it. Using 0011 on an 05 car. It its very rich upon start up. In the 11's. And will settle into an acceptable STFT once it reaches operating temp. I need coolant temp trims badly. It's been about 30f in the mornings here. Do I need to switch to a different rom to gain some more control over trims? There has to be a coolant trim table that can easily added into the xml. Dare I say, I'm desperate.

acamus

John,

Can you put some insight into MUT_C5 - MUT_2B and MUT_C6 - MUT_29 pairs.

I am little confused now as geekmapped states MUT_2B as coil energisation time.

But to me it seems MUT_2B is injector pulse width for 2nd bank of injectors, which could help those wanting to have two sets of injectors as for 6 cylinder engine design.

Thanx.

jcsbanks

I've not looked into cold start or trims, and I can't answer your question either acamus. It was a huge job just getting from the MAF interrupt to the "normal case" IPW, and it seemed to work for the purpose of replacing everything MAF related to produce a smooth, correct speed density. I know I did leave some compensations that were not MAF removal related to one side on the way. Most of them looked like they would be neutral in the normal case.

acamus

Lately I have been looking at the same. The MAF calculation code seems to be implementation of
US Pat. 4878386. I hope it will clarify the path.