High BLMs on 87 Turbo Regal

[gnvair]

I have been putting the car back together after being apart for many years. Engine is fresh......109 block, Champion irons, 206/206 roller, 60lb injectors, Translator with new plastic style GM 3.5 mass air sensor, Turbo Tweak chip, Racetronix 340 pump, adjustable regulator. Scanmaster to read data.
I followed Turbo Tweak instructions and have the fuel pressure at 43 (vacuum off). The car has been run in the garage only as it is not road worthy yet.
Originally the AF was at 4 and the idle BLMS at 137 . The Integrator stays at 128. I had a lot of issues getting the IAC numbers to stay put even after doing the procedure. The exhaust stinks. I have tried several GM oxygen sensors and they come out black and sooty. I pulled the spark plugs (CR43TS gapped at .030) and they are black as well. I have been checking for vacuum leaks and the only one I found was for the climate control head so I plugged that line off. I have not had much change in the BLMs. I noted that the AF was 4. I tried richening up the mass air on the dial in the Translator box and it went up to 6 but the BLM's didn't change.
I then tried increasing the fuel pressure up to 50 (using a rail mounted gauge which I dont know how accurate it is) and blms dropped to 134. I tried to increase fuel pressure more up to 60 psi and BLMs dropped to 132. I turned the pressure back to 50 and installed a new GM AFS 81 oxygen sensor (early 2000's vintage). After running for 5 minutes the BLMs went back up to 137 with the new sensor. I also noticed that the AF switches between 5 and 6. I pulled the number 1 and 3 spark plugs after all of this and they were wet. I am kind of at a loss as there is definitely something up with the black spark plugs and yet the high BLM numbers are indicative of it being lean and the computer adding fuel. I am not sure what else to try. I just dont want to wash out cylinders in a new engine.

 

[EricM]

If you're not driving it, and doing cold starts, then the plugs will get sooty, since they can't burn off and clean themselves.
I would leave the fuel pressure at 43psi, and MAF base setting at 0. Change the plugs also.
The AF reading looks about right.
The higher BLM could be a vac leak, and I would look at the PCV, as it may be passing too much air. 137 is not horrible for BLM though.
You might need to wait until its drivable to get a better idea, assuming it feels like its running ok.

 

[gnvair]

I put the mass air back to the base setting of 0 and the fuel pressure to 43 psi with vacuum off. I tried blocking off the pcv and it made no difference. I tried blocking off the vacuum to other items such as the vapor cannister and the map sensor. Still no difference. I put a vacuum gauge and had between 16 and 17 inches at 900 rpms. It seems to like idling there the best.
The blms settled at 134 and the mass air was at 5.
The 02 sensor voltage was very low. This was a brand new GM sensor. I hope I didn't kill it already.
I am wondering if my issue could be partially restricted injectors or a bad mass air meter. I posted a picture of the meter I have. It is the current Delphi replacement for the LS1 F bodies.

 

[EricM]

How is it running? Is it idling bad?
Was it idling in open loop or closed loop?

 

[gnvair]

This was all in closed loop and fully warmed up (175 degrees).
The idle isn't terrible. It's a 206/206 roller. It's been 11 years since I had this particular cam in a car so I can't remember what the idle vacuum should be.
The injectors have sat for a the same amount of time and I can't remember if I had Chuck Leeper service them.
It was hard to start when cold yesterday. I had to crack the throttle to get it started. I ended up resetting the idle speed higher to 900 rpms when hot. I still have very unstable IAC counts.

 

[EricM]

If the IAC is erratic and you have to crack the throttle to start, then the IAC itself might be bad or stuck.
By forcing the idle to 900rpm, you're basically bypassing the IAC, since it will be at zero at that point.

 

[gnvair]

What should it idle at with your 5.7 chip?

 

[EricM]

I normally set the chip for about 825rpm.

 

[gnvair]

I just received my injectors back from cleaning and flow testing. They are Siemens Deka 60's. The flow rates at 43.5psi ranged from 66lbs/hr to 70lbs/hr. Should I worry that they flow that much more than 60lbs/hr? I'm also curious if I should position them according to cylinders that are typically rich or lean?

 

[EricM]

Everybody flows them differently, with different fluids, etc, so it's common to see that variance. Looks like they are fine.
I would not be concerned about where you place them.