maybe it doesnt reference the tps sensor since that would be a decent amount of vacume and just assumes your not in the throttle... thats probably just wishfull thinking though.

I'm hoping it is a miracle and fixes it, but not holding my breath. I won't know until Thursday or Friday, the transmission is out of my car right now.:(

Well I only drive it when the roads are dry and the salt is worn off... which is not very much. Tomorrow it's suppose to rain all day.. that means clean roads unless it gets cold again.

I see a correlation between no 02's and a tuning problem. There's also a whole lot of guessing a Datamaster log could straigten out.
Looking at my logs.. I see 27kpa rarely. My log shows my having 27kpa cruising at 74mph with 2% Throttle and 1625rpm, and maybe the next lower gear while slightly accelling... 10%tps. I dont see a problem yet.

What was the reason for going completely open loop again? Possible to re-connect 02's? Tunercat has a setting to disable Closed Loop under a certain MPH as well.

If you've seen pics of my engine by and how clean it is, you'll undestand why I don't want to add o2 sensors back to it. All the wiring is gone for them, no way they can go back on my car. I prefer to commant what AFR I want, not let the computer do it.

I should know by the end of weekend a fix for this issue for those who want to keep the open loop tuning.

With my stall, gear, tires, etc, anytime I'm cruising around 35-50mph I hit the 27kpa cell a lot. I also it it when I come off a stop light about 5 feet out.

can you even use the o2 if your halfing the injector flow rate? i think the computer would just be over compensating.
or did you get away from that?

Eek. Mind sharing your setup so I can avoid it? haha j/k =p

Still works good down the strip im sure. Please keep us updated if you find a fix.

Well obviously you can becouse dookie is doing just that. MORE than just halfing the rate.

Yea I have closed loop with a decent cam 230/234 and it seems to work pretty good... no different from when I ran the 1 bar. When I ran the 1bar at one point I disabled idle closed loop (using speedo in TUnercar instead of anything else) and that worked good for whatever I was doing... now with the 2bar I re-enabled idle closed loop and it still seems to be ok.

I do have my injector flow way down (partly to fix lean tip in stumble using 83lb injectors) from what I understand the other way to compensate using the 2bar would be using the Cylinder volume? Not positive though.. either way the same result is achieved.

"1982z28with18s" - I see you have the stock cam.. that will make all the tables shift compared to what I see... that explains the difference.
I think the reason I didnt loose any driveability was because for whatever reason (and may be due to the cam) the values in my range of idle-cruise-mild load were maybe less curvy than what the stock cam needs... I know this is true with the timing curves but not sure about the VE tables... (I increased timing alot compared to stock in low rpm/load which essentially smoothed out the graph.. eliminating the need for extra tables there since some cells are so close to adjacent cells).

Do you have a Wideband like LM1? Now might be a good time to test the "simulate narrow band 02" output function.. I've been wanting to try this forever... I posted about it a while back.. I think it could potentially be a perfect solution for those with big cams and split BLMs.. as long as the computer accepts the signals and allow's closed loop.. you woud have to wire in both sides from the same signal but it might just work.. plus you might be able to log the AFR using the stock 02 pcm inputs in datamaster. Tunercat has some settings for 02's I dont know what they mean.. something about ranges. Might be do-able.

I don't have the stock heads/cam anymore, they came off this winter. It's a small xfi cam now with some Lloyd Elliot heads.

I have the lc1, not lm1, and I already have it wired into my pcm so it shows up in datamaster via the ac pressure like others have done in the past.

I'll know more in a few days when I get the car back on the ground with the transmission. The ONLY driveability problem I have is the 27kpa spot, all other spots are fine.

I did some homework for you...
http://www.turbododge.com/forums/f4/...og-signal.html
"My LC-1 has two analog (narrow band) outputs. It says that one can be hooked up to simulate the stock narrow band O2 sensor. It also goes on to say that some computers need the stock O2 sensors heating element hooked up and working or it will give the computer bad signals. It says to just hook it up and secure it somewhere."

I know all about that AC pressure input that's not what I was referring too... if you could.. hook it up to your O2 sensor PCM inputs and see what happens. It's ok having AC pressure input.. but would real "data capture", " or even better... "averaged bank to bank 02 circut/logging/fuel adjustment be better? Since your not using the 02 input's there really no reason not to try it.

Havent read about anybody doing it yet.. I posted about it just never tried it. Had a bunch of people theorize about how it wouldnt work but that was opposite of the point of trying it (those guys never tried it).
Bunch of guys said 2Bar reference wouldnt work for unknown reasons... those reasons were discovered to be BARO RESET.. we overcame that pretty quick once discovered now didnt we. Again, Tunercat has settings for O2's.. (specific voltage references...). I can only imagine that's for "non stock" 02 action.

My setup:

383 15lb boost, 226/236 cam on 114lsa, 9:1 compression or so, me and Dookie454 were playing around the same time with ours, I have no problems at all, no lean spots with 02 sensors in 27map range.

Like said, make sure you lower your MIN injector PW to around .5 or so which is what I did, you'll also notice that if you ever hit lower than 1.4ms which is stock MIN, your BLM will flatten at 128blm, when I first noticed it thats when I changed the MIN PW to .9 than to .5.

Also look at all map tables, update hyst to 1 instead of 2 ofcoarse, and make sure to bring your RPM/BLM map ranges to a usable area, keep 2 bar in mind when doing that as well, you want to look at your logs and see what rpm you spend most the driving at and MAP ranges, than dial it in, remember there are 16 cells total to use.

I also had to bring the injector constant to lower than half to take care of the lean tip in which was fixed after that was done plus lots more VE tunning with VE master.

But basically no problems what so ever here running 15lb boost, good through all RPM range, you can also change your low PW injector adder vs.Base pulse width, look at your logs, as you play with throttle you'll notice that when you tip in, your PW shoots up, but higher RPM free idle = less BPW, so you might want to actually do the opposite of stock, at lower BPW have less adder than at higher BPW, that helps in cleaning up your throttle response and also how well your BLMs settle down when coming to idle.


Also set my PE to come on earlier since with 15lb you hit boost very fast, so 66% TPS b4 PE at lower rpm is too high, by than I'm already at 5lb boost, set that to 50%.

Just takes lots of tweaking around, I spent maybe 20 hours in tunning, but I think everything is pretty much dead on.

Also my setup I just passed the IM 240 emissions test with flying colors :) So guess it runs clean too, just used the FLP stock cats, nothing special, and idle timing at 18*, the rest left it as is cuz I felt thats what the car liked.

I remembered I do notice a little roughness the first time I drive the car after a PCM flash while in open loop. within about 5 minutes of closed loop operation everyting smoothes out.

I think the o2s smooth this right out.. may fill in the gaps between cells so to speak.

Thanks for the info bunker! You are running with no Baro Reset right?

This is exactly my problem. 25 kpa is throttle on but slightly decelerating, while 30 kpa is throttle on and slightly accelerating. To hold constant speed in the 35 - 55 mph range required 27 kpa and it runs 17/1 A/F ratio.

Mike