I'll try to summarize as best as possible. EJ257 block, FP Green, cut stockers, as of last night, I put on the Perrin bigmaf...

I wanted to experiment with the launch control, but it seems like a few goodies have been added to that feature since I last had it hooked up ~a couple of years ago. Here's how I hooked it up: PIC (http://files.gpatmac.com/UTEC/launch.control.wiring.jpg).

Well, when I went to start it up this morning, It didn't want to start and then when it finally cranked, it idled very crappy. I unhooked the LC wires from the clutch and hooked up the cruise control connector. Still not good.

I figured maybe my map selector had maybe gotten bumped and was on the zero map. Because of the LC, I had the map switch on 9 which I understand is map 1/LC off. I pushed the button once and it went to 8 and the car idled smoothly.:huh:

As a note, this may not have anything to do with the LC nor remote switch as I also put the bigmaf on for the first time last night. For accomodating the bigmaf, I had left my stock fuel injector size to 420 but set my actual injector size to 650.

Last note, to ensure something wasn't amiss with my map selector switch, I unhooked it and ensured my UTEC switch was on the proper setting. Again, when I turned the red dial to where the dashboard said it was in map 0, it idled perfectly. When I set it to 1, it idled like crap.

In order to get back home this morning, I left it in 0. It drives fine. I logged a little on the way home and without pushing it too hard (but enough so that it would have switched to OLF and to UTEC timing control) it never took over from the ECU and the MOD MAF reflected the same values as the MAF column.

Any thoughts?:confused:

Your car is going to freaking explode!!!!

Thanks.

Your issue is likely related to the fact that the bigmaf is already applying a scaling factor to your cut stock injectors. They almost cancel each other out. This is why the car will drive ok in stock mode with a big maf without any further MAF corrections.

Set your injector scaling back to around 500/420 and check your fuel trims via OBD2 to see how close you really are. You might have to go a little lower on the injector flow rate value, but this setting should get you started.

-Nathan

Thank you.

Ironically, I actually decreased the value that I had from 750 (with an AEM CAI pipe, that I took a hacksaw, to and Greddy filter) to 650 for this bigmaf.

I think you've given me the true indication of my problem.;)

Fixed.:o:lol:

what did you end up with for scaling numbers pat?

Ken,

I can't yet answer. I did take it with me today and tried to do some stuff but it didn't result in much. I had checked my static trims and they were actually good, but when I got on the road, they were a little high then I blew an IC hose off. I had to call TXS and speak to Jermaine. I need to reset my ECU after I redo trims. It sometimes dies when I approach a stopsign.

I'll get back on it on the way home.

edit: oh, they start around -2 to -1 under 1.5k, then 1-2 up to 2k, then -3 above 2k.

Interesting. With a 3" MAF (but blow through) mine is set at 420/650 and is just about right. I suppose going back towards the 600 mark on the scale size might benefit my set-up but it's pretty close now by only observing the AFR behavior. I will say that at idle it prefers to fluctuate about 14.9:1 to 15.6:1. This is after some time of resetting the ECU. Cold start is more like 15:1 to 15.6:1

I wish I had access to an ODB2 reader with the ability to read ST/LTFT's but I don't so this is primarily on-the-fly for me. Although, my car idles better now than it did when stock ;)

Cold start & off throttle, I'm actually seeing 17's to 18's. I am way out of whack. Nathan's advice was spot on, but not without tuning; just to get the car started and to idle. I may end up at or near 650.

Cold start & off throttle, I'm actually seeing 17's to 18's. I am way out of whack. Nathan's advice was spot on, but not without tuning; just to get the car started and to idle. I may end up at or near 650.
you might want to check for a leak, post-turbo, pre-wideband. the car shouldnt feel "normal" at those AFRs. most likely, you are running fine at 14.7ish but your wideband is not right.

ps-the stock ecu will try to correct it and achieve a 14.7AFR anyways...so if anything, you should see it bouncing from 17s down to 14 or 13...you shouldnt see consistent 17 or 18:1 AFRs...thats usually indicative of a leak.

What does your name signify?;) I only ask because I usually like to refer to those on the board by first name who contribute and seem like they've got it all together.:) I've always wondered what your s/n signifies.

Anyhow, you're right but after taking Nathan's advice, the car now consistently runs stoich while in CLF operation while on my #1 map. I am STILL having difficulty in tailoring my trims, though, but they are manageable for driving around town. Except for one time, I have yet to really drive it outside of CLF. (A couple of days ago, I attempted a couple of tuning runs; first time, car knocked almost immediately...this is after I had applied a + across my whole 10-100% portion of my fuel map. Second run, I blew off an IC hose which pretty much halted my tuning for the day.)

With regards to my fuel correction #1 and fuel learning #1, I am chasing values around. I log with DD, make corrections with UTEC, reset ECU (gun throttle a few times), log with DD.... See: abreviated DD log - excel format (http://gpatmac.com/files/UTEC/MAR06/Deltalog-trims.xls)

I do have an unrelated to the topic question, though. While in CLF, what AFR's should I be targetting and where? (note, as soon as I post this, I am going to reread Mick's guide looking for this answer.) While transitioning from CLF to OLF, what should my AFR's be and where, ie. slow acceleration from, say, 2000rpm to 5500-6000rpm?

Again, see linked UTEC log in excel format (http://gpatmac.com/files/UTEC/MAR06/14mar5.xls) of slow throttle, mainly in less than 10% load.

Pat,

in the 0% (vac - 0psi) CLF you will be about or near stoich. The higher the rpms the more you'll want to splash so fuel in there. That's light throttle, increasing rpms. Think NA.

Todd

Todd, my thinking is even way slower than na.;)

So, below 10% MLP but at greater than 5000 rpms, 14.7:1 is still safe?

My concern, too, is how quickly and how much of a jump should I make the transition from CLF to OLF. I know that this question is found in a quick search, I just figured with the log above, any advice I may get would be personalized.:)

I'm just thinking that at 5krpms you defnitely don't want to be 11.7:1 and 3in hg of vac (from your log). What would be the purpose of dumping fuel like that at a barely any TPS (14 IIRC)? If you've ever seen logs from NA motors even under WOT loaded up they are no where near that point. I think you would be fine at 13.5:1 in that area.

Ah, it took me a minute to process.

The reason my mod fuel is 6 is because the only way I've been able to get the fuel trim down from +25 was to add fuel. It started at a little over 3.

I mean, I'm looking at that log, looking for any disparities. It's full of them. MAP increases a bit, which triggers the AFR's to begin getting leaner. Then, MAP decreases but AFR's continue to get leaner (RPM's have steadily increased all the time.)

SO, 11-ish:1 AFR mainly all before it gets into the 10% column, then once it gets into the 10 column, AFR's are nice and rich again.

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