If he is running the 7747 without a knock sensor and has not turned off the forced knock test there is a good chance its the test itself not the spark map causing the knock.
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definitely good info, especially about the plug wires and shielding the pickup wires. i've gone through the exact same shit another car before, and now you reminded me to check mine out.
but yeah it does sound like it needs a retune
AFTER you resolve all other possible issues.
If he is running with no knock sensor and it is not turned off properly in 1227747 then the knock count just keep counting and pulling knock retard timing.
The forced Knock test is run during PE, WOT... just when you need forced knock right? D'oh!
If you have some high pixel size pictures of under hood EFI install I can usually spot any issues like high voltage RFI noise interfering!
It's time for you to get a ALDL cable and TunerPro RT to do some data logging! We'll find the issue.
AFI used to have great customer service... when I worked there!
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Even if Dave W from Old School does not have time I'm sure he will help you get TunerPro RT setup and working on your Laptop! Then we have something to look at and see what's going wrong.
It sounds like your fuel maps are pretty good if it runs well after a ECM reset. Sometimes these old engines don't like to run at Stoich which is what the O2 sensor and BLM learn is what they do. The way to tune an engine that needs to run Open Loop is with a Wide Band and take the O2 sensor out!
This still leaves your timing issue! As you've been recommended get a GM ICM, it is an important part and aftermarket ICM have been proven to be in-accurate with timing. There could still be other installation/conversion issues. If you were closer to Coeur d'Alene Idaho I fix these conversions all the time.
You say the injectors flow at 180? 180 what? These TBI injectors are usually pound per hr. If you look on the top there are some numbers, write them down and let us know what they are and we can tell what size. Running at 26 PSI is very high pressure...
Wish you the best! Good Luck! :rockon: