Engine Problem
Run State doesn't matter. Your AFRs look good. That is the important thing. The unit is doing it's job.
I would start looking at ignition and valve adjustment. Doesn't seem to be a Fitech issue. At least what I can see.....
Have you looked at the plugs?
That's on schedule for tomorrow. I'm gonna hook the timing light to each plug wire and make sure they are firing. If they pass that, I'm gonna pull a couple plugs to see what they look like.
Do I need to worry about the 105 (O2 Sensor) trouble code that has popped up a few times?
Valve adjustment will follow after that. It would suck to think that is off. 5000 miles on the motor built by a Pontiac pro builder. Pretty easy miles on it as well.
I wouldn't worry about the code.
I learned that the FITECH does not heat the O2 sensor and it will show a fault for the first second or two until it warms up.
It was ignition related. I found the #4 plug was firing erratic. I replaced the plug and it wasn't as tight as I would have thought. It looked like it had a bit of fuel residue on the head around the plug. I think it may not have been fully sealed letting air in and getting some blow by on compression. Changing the plug did not solve the erratic spark.
Pulled the cap and found the adjustable rotor tension screw had loosened up. Set it back to the witness marks and tightened it up. After I started it, it would rev past idle like it should. Checked the timing at 2000 rpms and it apparently the witness marks were accurate as it was spot on.
Thanks for your help.
Went for a test drive and readings on the handheld were noticeable smoother. What I really liked was MAP readings at 70 mph dropped from 45-48 to 37-38. Engine is working much easier now. Can't wait for it to tweak the maps over the next few drives.
That's awesome. Glad you worked it out. I will remember that for the next guy.
Just to update you further in case you run across something weird in the future. Checked the remaining 7 spark plugs and found 6 of the 7 looser than I would have liked. They weren't sloppy in the threads loose, but would take some a 1/4 turn on the ratchet. On the plugs I could see, I found fuel residue around the plug holes. I would guess I was getting some faint blow by on compression and some un metered O2 on intake stroke.
MAP and AFR readings are so much more stable now. I'm guessing I had the problem since before I started the FITECH conversion as I've never seen readings this smooth. Now that I have seen how the readings should look, it will be easier to see when something is amiss. Just in a couple of drives around town, it has fine tuned the tables so much that trim numbers are more consistently +/- 3 with a lot of time in just sitting at 0.0!!!
I never would have thought to look for loose spark plugs if I hadn't been forced to. Car always ran pretty good before but its night and day difference, so much smoother and quiet now.
Thanks again. I can't stress enough to anyone reading, no matter how new the parts or how well you think you have it installed, make sure the details are spot on for the fuel injection to perform at its best.
Martians, don't beat yourself up. After my success with my first unit on the 67 C10, I was very confident to install one on my Camaro. Got everything set up, did a break in and then it wouldn't start again. The handheld was doing weird things and the fuel pump stayed on constantly. Myself and buddies scratched our heads for 3 days. Pulled all my custom waiting apart. Could not figure it out. Finally realized I didn't tighten the the carb studs. The unit was getting a bad ground. I felt like a dummy.
One of the many reasons I started this site....😁