PDA

View Full Version : Installed PFC now won't idle for shit


Kouki
03-19-2008, 08:49 PM
Like the title says, car ran good last year. Put in the power fc, now the idle is all over the place, I was trying to do the idle learn procedure and it was going from like 1200 to 200 and everywhere in-between, it would keep itself running, would free-rev fine, but when I let off then it would die. Is this normal during the idle learn on the pfc? Or could my MAF have gone bad just sitting over the winter? Would having the base timing set at 10dbtc cause this? I wanted to get the timing set but couldn't get a good reading with the idle being so rough. My air/fuels were also jumping all over between like 9.5-18.5 but I'm assuming that this is because of the idle being so shitty. Is there a good way to test the maf so I can eliminate that? Nobody I know around here has one that I can plug in and see if there is a difference.

Please help, I just want to get this thing running so I can get to the dyno and get it tuned.

flip3d
03-19-2008, 09:30 PM
I thought you had the load the base map for your engine before even hooking it up?

Yuda
03-19-2008, 09:37 PM
hmm. is it completely stock? if not then you may have to adjust things on there. whenever i had problems i would contact apexi and talk to masaki. hes the most helpful. other than that if you bought it from a power excel shop you could ask them for assitance.

Kouki
03-19-2008, 09:43 PM
They come with a preloaded base map for the application, but I'm not using that, I'm using enthalpys base maps. The car is pretty far from stock. But either way, I would think with the injector size set, and correct MAF selected that it should idle fairly good, now cruising and WOT are a different story.

jspaeth
03-19-2008, 09:51 PM
They come with a preloaded base map for the application, but I'm not using that, I'm using enthalpys base maps. The car is pretty far from stock. But either way, I would think with the injector size set, and correct MAF selected that it should idle fairly good, now cruising and WOT are a different story.


Agreed...I recently installed a D-Jetro PFC, and it idled fine right away....

Do you have O2 feedback turned on or off?

Blown240sx
03-19-2008, 10:56 PM
I had the dieing issue and I just kept starting it till it ran. I also turn the boost and O2 control off. Since once you tune you wont need the O2 anyway.

sr20kouki
03-19-2008, 11:02 PM
mine ran fine as soon as i plugged it in...mine was far from stock as well

Kouki
03-19-2008, 11:13 PM
I had 02 feedback turned on, but I wouldn't think that would make it run like it did, I'm really thinking my maf took a shit on me. I'm kinda gunshy to buy a used one though, as the first one I bought was junk, bought a second one(current) ran good all last year and now it took a shit on me too. I don't want to have to spend over 200 for a new one only to find out that mine is fine.

Sileighty_85
03-19-2008, 11:42 PM
when you install the PFC for the first time the PFC Has to run the Self Learing Idle Adjustment Sequence, it will learn the Idle and sensors, you let it run for 10 mins with "Nothing" on, then turn on Rear Defroster for 10 mins, then the AC for 10 min.
The Idle will jump around durring this process then it should steady out

If you touch the gas or do anything else durring this process (That puts a load on the eninge) it will throw it off, so you would have to re initalize the sequence over again

steve shadows
03-20-2008, 09:18 AM
Like the title says, car ran good last year. Put in the power fc, now the idle is all over the place, I was trying to do the idle learn procedure and it was going from like 1200 to 200 and everywhere in-between, it would keep itself running, would free-rev fine, but when I let off then it would die. Is this normal during the idle learn on the pfc? Or could my MAF have gone bad just sitting over the winter? Would having the base timing set at 10dbtc cause this? I wanted to get the timing set but couldn't get a good reading with the idle being so rough. My air/fuels were also jumping all over between like 9.5-18.5 but I'm assuming that this is because of the idle being so shitty. Is there a good way to test the maf so I can eliminate that? Nobody I know around here has one that I can plug in and see if there is a difference.

Please help, I just want to get this thing running so I can get to the dyno and get it tuned.

BDTC needs to be at 15 this would cause a low idle.

Turn off all the other closed loop functions as well. ALL OF THEM to start

use a .16 on the inj time, maybe .22 what size inj you have? :zzz:

Kouki
03-20-2008, 08:53 PM
BDTC needs to be at 15 this would cause a low idle.

Turn off all the other closed loop functions as well. ALL OF THEM to start

use a .16 on the inj time, maybe .22 what size inj you have? :zzz:

Alright, I did some playing around with stuff tonight. Think I've got it straightened out. First off, I was having a hard time setting the timing on it last night, which I thought was because of the crazy idle, turns out that my timing light didn't like the SR, used a cheapo timing light, bam worked perfect, I was at like 5degrees btdc, set it to 15, AMAZING difference. I thought that timing had something to do with it, but didn't think it was that bad. Also turned off 02 feedback, that smoothed it out even more.

So when you say .16 or .22 inj time, are you meaning for the lag time, or for cold start enrichment? I've got 740s in there now.

Also, in the datalogit program, is there a way to view "realtime" values of everything, or just log it and open the log to see what happened once you're done?

steve shadows
03-20-2008, 09:51 PM
lag time you can play with it between those margins, you should be able to find out optimum from the manufacturer or online however.

Kouki
03-24-2008, 10:27 PM
lag time you can play with it between those margins, you should be able to find out optimum from the manufacturer or online however.

I have deatschwerks injectors. They said to use 0 for the lag time, same as stock. Tonight I changed my lag time, as you said, and saw a HUGE difference in the way it idled, smoothed out alot! Still a lil rough, but damn close. Is having the lag time set here going to affect anything in a negative way? If not, I may try to turn it up a little more and see if it gets even better, but don't want to if I'm going to have negative side effects.


I'm going to the dyno tomorrow for some tuning. I wish I could have had some time to get some street tuning done, but apparantly my innovate wideband is a piece of shit, or I should say a pain in the ass to get set up correctly, it's just too picky about everything and can't get it to read right for more than 5 min of idle time. So I guess I'll have to use their wideband at an additional cost, and hope my AEM uego arrives soon.

Sir
03-25-2008, 09:33 AM
deathwerks injectors might be the problem. I've seen too many people complain about them.

here's some examples from JimWolf
http://www.jimwolftechnology.com/wolfpdf/DRILLEDINJECTORSVSNEW.pdf