strider681

alright so I got a chip programmer mainly to switch to the $6E code so I could remove my cold start valve. the car starts up alot easier now, and seems to run a little better too! my question is that I installed a "cold air" intake and am wondering what mods to the programming are needed? I can see that the $6E already changes and smooths out the MAF scalars and tables. Thing is car runs pretty good, but on my scan tool the BLM for cell 0 (idle) goes to 160 but the INT stays 128. at part throttle BLM goes to 133 and INT stays about 128 or a little higher. I don't have any apparent enough vacuum leaks that I can hear, but my passenger side exhaust manifold one of the studs broke off and it's not sealing all that well on one nut. but could just having basically an open air element on the intake cause 160 BLM at idle and if so what should I change in the PROM to compensate? I am using ANYJ as a base cuz I have the 2.77 rear axle. I have reset min air a few times. I have original stock injectors that I sent out for cleaning/testing to cruizin performance recently. all came back good flow. I put on a crane AFPR and increasing fuel pressure barely brings the BLM down from 160 to maybe 154. i get the 160 BLM with either my original chip or $6E. so I'm gonna keep looking for air intake or exhaust leaks, but I thought I'd see if anyone had to tune for a more open air intake and what they did. I searched alot but couldn't find much.

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305sbc

Before you can effectively troubleshoot anything for closed-loop operation you must eliminate ALL exhaust leaks ahead of the O2 sensor.
It's really not an option.

__________________
http://www.misterfixit.com/deton.htm
http://www.gofastnews.com/board/tech...d-airflow.html

strider681

ok so even though the leak is not right by the O2 sensor it's on the passenger side it could still be causing my high BLM? I wasn't able to get the jack under the exhaust pipe to lift it up a little and make the connection tight. idk tho seems like vacuum leak to me cuz i got it to go down with all the crap i've been doing, now it's about 138 BLM and 128 Int at idle. one thing is i replaced that gasket under the "tuned port injection" plate on top of the throttle body. but i did also change the table "injector PW correction vs battery voltage" to match my old BIN, which had slightly higher values for the 11-14 volt range. i don't want to just add fuel to offset some kind of vacuum leak or mechanical defect. but that's why i asked about having a more open air element when using a MAF setup, do you have to add fuel in the programming for that? because stock air boxes only have little slots for air to come in, now i have a 3" pipe with a filter on the end i'm sure I need to change somethin for that. sorry i'm real new to programming chips but i think i'm geting the hang of it. any help is appreciated. one note is that it runs better when in open loop cold and once it warms and the O2 kicks on it creeps the BLM up to 140-150 range at idle. on accel both values go to 128 and the O2 sensor reads very low (30-50mv) and lean flag is set doesn't ever go rich. but at idle once the BLM goes to 140 or so it will go lean/rich like it should every second or two. last thing is when i put back in my original chip unmodified it sounded like crap, guess cuz all the extra timing it has.. alot more than ANYJ and i think the BLM and INT were higher iirc

Edit: just want to add that I read all the articles about general info and tuning the PROM and it definitely mentioned changing the MAF scalars and tables if your using an open element air intake. although it doesn't give specific examples just said to make scalar value higher to reduce BLM i think. but then you gotta recalc the table and i'm worried about messing with those. I found a BIN (AUJM) that has MAF scalar #1 of 18 where ARAP has it's vlue at 17. but some of the values in the table are smaller. which i understand from the articles that the tables used with scalar need to make 255 gr/s total right? i need to go back and find the calculation or i'm not sure if they listed one.. honestly my eyes were watering but i soaked up alot of info.

strider681

alright went at it again all day today and still no luck. I changed the distributor base to intake manifold gasket, replaced my A.I.R. hoses and one of the check valves. since it was still doin same thing I put it up on ramps and jacked the passenger side exhaust up to make the connection there tight (missing a stud) and still same problem. performed a compression check and all cylinders read 148-152 engine warm except #2. this sucker went to 180. anyone know what causes that? and since 2 is opposite 7 on the firing order, and #7 is the one with the noisy vlave that gets worse when fuel injector is unplugged, could that be my problem? when I was doing the compression test I noticed 2 of my exhaust manifold bolts were loose, so I went around and tightened them all and most were loose, thought for sure that would do it and BLM only went to 134 for a few min then i revved it a few times and something happened like something warmed up and took a dump cuz then the BLM shot to 152. thing is too my IAC was reading higher counts meaning it was using more vacuum leak to make idle. then when the BLM drop do did IAC down to like 10-15. guess next step is to pull valve covers and check out my valve lash. the car is def running lean, when i pulled out the spark plugs they all had this black mark on the insulator and tips where tan/white. book says overheating, basically running lean causes that. I did try setting my injecotr constant in the PROM from 22.36 to 24lb/hr. that should give it more fuel right? well didn't really change much. basically after the valve covers and lash and trying my old air box I'm pretty much out of ideas and will prob have to take it in to a shop bummer

strider681

well I fixed a multitude of problems I had with this car, basically i took off the valve covers and a couple of rockers were loose and I found a bent push rod on #2 intake valve. after replacing that and new valve cover gaskets, I also replaced exhaust manifold gaskets and fixed the broken stud. so now I basically have nothing mechanically wrong, all exhaust leaks fixed and what not.

so in trying to tune for the open element air intake I have, I added to the BPW by changing the table "Injector PW Correction Vs. Battery Voltage" I changed the values for 12.8 and 14.4 volts to 1007.00 and it seems to make the BLM happy at idle. but while driving around, the BLM go lean on acceleration (140) and a little rich on decel (122) I have read from grim reaper that I need to change the MAF tables and maybe scalars to get the precise tune on this. my original values for 12.8 and 14.4 volts were 793.47 and 610.36 respectively. so i had to add either 200 or 400 usec to make my BLM happy at idle and ok driving. my question is that alot for no mods besides open air element and 48 PSI base fuel pressure (no vacuum)? and is there a formula or something to figure out how much to change my MAF tables? i've read alot about it recently but I still don't have enough confidence to just start messing with them yet. well any help is appreciated.

strider681

to close up this thread i ended up adjusting only my BPW by 12% to compensate for the extra air i was sucking. I forgot that I had removed the little walls in the plenum awhile back, that along with open air element was causing my ECM to add fuel. after adjusting it the 12% my BLM and INT are where i want them and I passed emissions with flying colors, barely putting anything out.. granted i had put on a new cat and muffler didn't wanna take chances