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corsair231
10-24-2005, 02:52 PM
Trying to get my combo sorted out but I'm getting some conflicting numbers on my scan tool. My blm was at 105. My IAC was a constant 70. I heard that IAC could impact blm, so I did the IAC reset procedure. It was a little pita and after several tries I ended up with a IAC of 17. Just couldn't seem to hit the low 20's. Reset the TPS koeo .40, wot 4.60. At idle it is about .42. Idle is around 750-825. FP set at 42# hose off. BLM is still 105, int < 128, which means the computer is pulling fuel to combat a rich condition right? O2 millivolts were at 460 which is lean isn't it? O2 crosscounts were changing. The Scanner showed closed loop and changing from rich to lean and back like it is supposed to (but it doesn't seem to do it as fast as it does in my 90 Lesabre 3.8). What direction do I need to go? Do I need to change fp or should I suspect my O2 sensor and just throw in a new one? I'm not sure of the chip maker so that may be questionable as well. There's an off idle tip in stumble I'm trying to cure along with the best tune possible. Car drives fine otherwise, mileage may be a little down. Plugs are R42ts gapped at .035". Mods are in signature. Thanks

Keller
10-24-2005, 07:34 PM
Really, it sounds like you've done everything right. Trying to tune it correctly. Its just that your BLMs are parked at 105 - not good.

O2s in the 400s at WOT is WAY lean. Like, oops-I-just-blew-two-head-gaskets-lean. Though not so much at cruise. Do you have any WOT O2 numbers? Is it safe enough to get them?

What sort of MAF do you have? Any air leaks in the intake / intercooler tract? Do you see 255 on the MAF at WOT?

Barring problems there, my guess would be that the chip is not calibrated for those injectors. Do you know whose chip it is and if it was programmed for those injectors?

Good reference at http://www.gnttype.org/images/blmint.gif

corsair231
10-28-2005, 12:58 PM
I don't have any wot numbers. I'm still having problems getting my boost dialed down enough with 93. I can't get it low enough to not knock without adjusting the actuator to hold the puck open all of the time and then it spools so slow. Right now I am still using the stock wastegate control which seems to be working correctly. The wastegate hose is in good shape and it has the correct y in it. I'm thinking of putting another restrictor may be after the solenoid to limit the amount of air it will flow. I've heard of people blocking off the filter side of the solenoid to drop boost but that takes all of the control out. The lowest I can get is about 19#'s with the puck just closed and no preload tension from the actuator. Actuator moves with air pressure on it and seems to have full range of motion. I guess I probably have a HD actuator (not sure how to tell but it seems to have a strong spring) which may be why I can't get it low enough.
I'm using a stock aftermarket replacement MAF with one screen. It is not necked down and reads 6 at idle. I'm using a bigmouth cai with solid pipes. I have not been able to find any leaks using carb cleaner around all of the usual places. Not sure of the chip maker but it is marked 009's. One thing is that the prom id changes on the scan tool. May be due to custom programming using maps from two different files? It is supposed to be a street chip with 17# boost. I do have a 009 strip chip but I haven't tried it yet due to octane, but maybe I will to see if the blm's change at idle. What I don't understand is if the O2 is reading lean then why is the computer pulling fuel with a int of <128? Seems like it would be adding fuel. Maybe it's time to give TTweak a call and get a new chip. Thanks for the help Keller.