I have a new TBI system setup on an International Harvester 345 engine.
Gas tank has been removed and cleaned.
Followed the setup procedures and set the TPS to .57 volts. Set the IAC to 450 rpm. Timing is a 0 degrees and the fuel pressure is 13 psi. The TBI is off a 92 Caprice with the Cop Car injectors. GM part # 17084327. I have a Truck ECM 1227747 stock chip. The engine starts and runs fine and idles around 700 rpms and the BLM is 128.

Edit... The dissy is a GM /IH hybrid. Top is GM, but the gear is IH.

This issue

Running on the freeway 2,500 RPM's the BLM are rich (appx 120), But then I get off and back on and the BLM jumps to 150.
Looking for ideas on what might be the cause. Bill USN-1 has been helping me, but I thought maybe a few more eyes on this and somebody might have seen this type of issues before. Thanks in advance.


Here I'm on the Freeway, just left the house.


About 8 miles later and turning around.


Getting up to Freeway speed.


Now at freeway speed and the BLM is now 150, and the IAC is also higher?

 

Problem fixed. Some dummy (me) had a stock 7.4L chip in the ECM.

Put a 5.7 in there and now I can start logging some data.